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1.
J. bras. pneumol ; 45(3): e20170164, 2019. tab, graf
Article in English | LILACS | ID: biblio-1012550

ABSTRACT

ABSTRACT Objective: To evaluate the pulmonary alterations of animals with Hepatopulmonary Syndrome (HPS) submitted to Biliary Duct Ligature (BDL), as well as the antioxidant effect of Melatonin (MEL). Methods: Sixteen male Wistar rats, divided into four Sham groups: BDL group, Sham + MEL group and BDL + MEL. The pulmonary and hepatic histology, lipoperoxidation and antioxidant activity of lung tissue, alveolar-arterial O2 difference and lung / body weight ratio (%) were evaluated. Results: When comparing the groups, could be observed an increase of vasodilation and pulmonary fibrosis in the BDL group and the reduction of this in relation to the BDL + MEL group. It was also observed significant changes in the activity of catalase, ApCO2, ApO2 in the LBD group when compared to the other groups. Conclusion: The use of MEL has been shown to be effective in reducing vasodilation, fibrosis levels and oxidative stress as well as gas exchange in an experimental HPS model.


RESUMO Objetivo: Avaliar as alterações pulmonares de animais com Síndrome Hepatopulmonar (SHP), submetidos à ligadura de ducto biliar (LDB), bem como o efeito antioxidante da Melatonina (MEL). Métodos: Dezesseis ratos machos da espécie Wistar, divididos em quatro grupos: Sham, Grupo LDB, Grupo Sham + MEL e LDB + MEL. Foram avaliadas a histologia pulmonar e hepática, a lipoperoxidação e atividade antioxidante do tecido pulmonar, diferença álveolo-arterial de O2 e relação peso pulmonar/peso corporal (%). Resultados: Quando comparados os grupos, observamos um aumento da vasodilatação e fibrose pulmonar no grupo LDB e a redução deste em relação ao grupo LDB+MEL. Observamos ainda alterações significativas na atividade da catalase, PaCO2, PaO2 no grupo LBD quando comparado aos demais grupos. Conclusões: A utilização da MEL demonstrou-se eficaz na redução da vasodilatação, níveis de fibrose e estresse oxidativo assim como na troca gasosa em modelo experimental de SHP.


Subject(s)
Animals , Male , Hepatopulmonary Syndrome/drug therapy , Lung/drug effects , Melatonin/pharmacology , Antioxidants/pharmacology , Bile Ducts/surgery , Blood Gas Analysis , Lipid Peroxidation/drug effects , Catalase/analysis , Hepatopulmonary Syndrome/physiopathology , Hepatopulmonary Syndrome/pathology , Disease Models, Animal , Arterial Pressure/drug effects , Glutathione Transferase/analysis , Ligation , Liver/drug effects , Liver/pathology
2.
Acta cir. bras ; 32(8): 633-640, Aug. 2017. graf
Article in English | LILACS | ID: biblio-886223

ABSTRACT

Abstract Purpose: To evaluate the effect of hyperin in cisplatin-induced liver injury in mice. Methods: Mice were pretreated with hyperin at doses of 25 mg/kg and 50 mg/kg, respectively, for six days, and intraperitoneal injection of cisplatin (40 mg/kg) was administrated one hour after the final intragastrication of hyperin. Twenty-four hours later, blood and liver were collected for further research. Results: A single injection of cisplatin (40 mg/kg) for 24 h significantly increased serum alanine and aspartate aminotransferases (ALT/AST) and gamma glutamyl transferase (GGT) activities, whileas hyperin reversed cisplatin-induced such increases. Liver histopathological examination further demonstrated the protection of hyperin against cisplatin-induced liver injury. Further results showed hyperin reversed cisplatin-induced the increase in content of malondialdehyde (MDA) and the decrease in level of total antioxidant capacity (T-AOC) in liver. Moreover, hyperin increased the levels of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), glutathione-s transferase (GST) in cisplatin-induced liver. Conclusion: Hyperin inhibits cisplatin-induced hepatic oxidative stress, which contributes greatly to the amelioration of cisplatin-induced liver injury in mice.


Subject(s)
Animals , Male , Quercetin/analogs & derivatives , Aspartate Aminotransferases/metabolism , Cisplatin/adverse effects , Chemical and Drug Induced Liver Injury/prevention & control , Antineoplastic Agents/adverse effects , Antioxidants/pharmacology , Quercetin/therapeutic use , Quercetin/pharmacology , Reference Values , Lipid Peroxidation , Catalase/analysis , Random Allocation , Reproducibility of Results , Cisplatin/antagonists & inhibitors , Oxidative Stress/drug effects , Alanine Transaminase/metabolism , Chemical and Drug Induced Liver Injury/pathology , Glutathione/analysis , Glutathione Peroxidase/analysis , Glutathione Transferase/analysis , Liver/drug effects , Liver/enzymology , Liver/pathology , Malondialdehyde/analysis , Mice, Inbred ICR , Antioxidants/therapeutic use
3.
São Paulo; s.n; 2016. 129 p. ilust, tabelas.
Thesis in Portuguese | LILACS, Inca | ID: biblio-1178137

ABSTRACT

O carcinoma de pênis (CaPe) corresponde a uma doença maligna mutilante do homem. É mais frequente em regiões economicamente desprivilegiadas, como o Norte/Nordeste do Brasil, onde frequentemente é diagnosticado como doença mais avançada. Assim, novos marcadores diagnósticos, prognósticos e preditivos de tratamentos terapêuticos ainda são necessários. Abordagens proteômicas, incluindo o MALDI Imaging, podem contribuir neste sentido. Esta técnica emergente de espectrometria de massas permite a visualização da distribuição espacial de centenas de dados moleculares diretamente da superfície de uma secção tecidual, adquiridos por razão massa/carga (m/z). Neste contexto, nosso principal propósito foi integrar dados de proteômica clássica (gel 2D e Cromatografia Líquida acoplada à Espectrometria de Massas) e de MALDI Imaging, para obter padrões diferenciais de proteínas associados com amostras de Carcinoma Epidermoide Peniano usual (relacionado ou não ao HPV) e espécimes normais, a fim de buscar possíveis biomarcadores da doença. Um total de 45 amostras de CaPe, congeladas, foram inicialmente genotipadas para a presença do HPV. Destas, 60% foram positivas para variantes virais de alto risco. A proteômica clássica (N=24) evidenciou níveis diferenciais de 35 proteínas entre amostras de CaPe e controles, e 29 entre CaPe HPV positivo versus negativo (P<0,05; ANOVA). Redes de interações demonstraram que estes perfis proteicos interagiam com clusters de proteínas relacionadas com a carcinogênese e progressão tumoral. Entre eles, se destacaram aqueles formados por proteínas antioxidantes e de adesão celular, presentes em níveis elevados em tumores HPV negativos. A partir dos interactomas, quatro alvos proteicos foram selecionados para a análise in situ por imageamento: Calreticulina, 14-3-3 sigma, Serpina B5 e Glutationa-s-transferase. A aquisição de dados do MALDI Imaging foi conduzida após a digestão in situ pela tripsina, usando uma resolução de 200 µm e faixa de 700-3500 m/z para peptídeos (N=31). Os dados de identificação do gel 2D foram então integrados aos do imageamento. A identidade proteica dos filtros foi confirmada, in silico, por meio da presença de peptídeos teóricos co-localizados com o peptídeo experimental alvo nas secções de CaPe. Não houve associação significativa entre os parâmetros clinicopatológicos e as intensidades de sinal dos alvos (P>0,05, U de Mann-Whitney). Análises não supervisionadas, realizadas a partir dos dados do MALDI Imaging, evidenciaram mapas de segmentação que coindiciram com as regiões tumorais e margens adjacentes livres de neoplasia. Entre os principais valores de m/z diferenciadores estava o pico 1413 ± 2,5 Da, abundante nas regiões tumorais, e correlacionado ao peptídeo experimental m/z 1410,86 referente à proteína Calreticulina (CRT), o. Análises estatísticas (PCA e Curva ROC) indicaram este valor de m/z como potencial biomarcador da doença. Por conseguinte, a CRT foi selecionada para a etapa de validação por imunoistoquímica em tecidos parafinados de CaPe (N=158). Níveis elevados de imunoreatividade da CRT foram associados com piores tempo de sobrevida global (Razão de Risco 2,3; IC-1,46-3,96; P<0,001) e câncer específica (Razão de Risco 4,37; IC-1,66-11,51; P=0,002) nos casos de CaPe. A presença de metástase em linfonodos foi considerado um fator prognóstico independente para o risco de morte pelo câncer (Razão de Risco ­ 14,18; CI-3,29-61,12; P <0,001). A imunoreatividade da CRT também foi capaz de predizer a presença de metástase em linfonodos (Chance de Risco: 1,006; IC- 1,0001-1,0012; p=0,044). Estes dados, em conjunto, sugerem que a CRT pode ser um potencial biomarcador prognóstico do CaPe. A estratégia de integração da proteômica clássica com o MALDI Imaging, mostrou-se uma ferramenta útil na busca de novos biomarcadores para o CaPe. Além disto, o trabalho adicionou uma visão analítica à histopatologia clássica, o que deverá inserir as técnicas utilizadas neste projeto em estudos de Anatomia Patológica, tanto em nossa instituição, quanto no contexto global.


Penile cancer (PeCa) corresponds to a mutilating malignant disease in men. It is more frequent in underprivileged socioeconomic regions (e.g., Noth, North-East of Brazil), where it is frequently diagnosed in advanced stages. Thus, new markers are still needed for early diagnosis, prognosis and prediction of therapy. Proteomic approaches, including MALDI Imaging, could assist in this effort. This emerging spatially resolved mass spectrometric technique can obtain topographical distribution of hundreds of molecules directly from the tissue section surface, mensured by mass/charge ratio (m/z). In this context, our mainly propose was to integrate classic proteomic data (2D gel and Liquid Chromatograph coupled with Mass Spectrometry) with MALDI Imaging to obtain diferential patterns of protein associated with Usual Squamous Cell Penile Carcinoma (HPV related or not) and normal specimens, to look for possible biomarkers of the disease. A total of 45 fresh-frozen PeCa samples were initially searched for HPV genotype, 60% of which were positive for high-risk HPV. Classic proteomics (N=24) demonstrated diferential levels of 35 proteins comparing PeCa and control samples, and 29 comparing HPV-positive versus HPV-negative PeCa samples (P<0.05; ANOVA). Protein networks showed that these protein profiles interact with clusters of proteins related with tumorigenesis and tumor progression processes. Among them, antioxidant and cell adhesion proteins play a critical role in HPV negative penile tumors. Based on interactome data, four protein targets were selected for in situ analyses by imaging: Calreticulin, 14-3-3 protein sigma, Serpin B5 and Glutatione-s-transferase. MALDI Imaging data acquisition of peptides was conducted after in situ trypsin digestion using a lateral resolution of 200 µm, covering the range 700- 3500 m/z (N=31). After that, 2D gel based proteomic data was integrated with Imaging data. The filter protein identities were confirmed in silico by the co-localization of theoretical triptic peptides with the experimental peptides in PeCa sections. There was no significant association between the clinical and pathological parameters and the target signal intensities (P>0.05; U de Mann-Whitney). An unsupervised clustering analysis based on MALDI Imaging data reveled segmentation maps that coincide with histological annotation for tumor and adjacent non-neoplasic regions. Among the mainly differentiating m/z values there was 1413 ± 2.5 Da. This peak was especially co-localized with tumoral regions and correlated with Calreticulin (CRT) experimental peptide (m/z 1410,86). Statistical analysis (PCA and ROC Curves) indicated this m/z value as a potencial biomarker of the disease. For this reason, CRT was selected for validation by immunohistochemistry performed on paraffin-embedded PeCa tissues (N=158). As result, CRT hiperexpression in PeCa tissue increased the risk of unfavorable overall survival (Relative Risk ­ 2.3; CI-1.46-3.96; P<0.001) and cancer specific survival (Relative Risk ­ 4.37; CI-1.66-11.51; P=0.002) in these patients. Lymph node metastasis represented an independent prognostic risk factor for death related to cancer in our patients (Relative risk ­ 14.18; CI-3.29-61.12; P <0.001). CRT immunoreactivity was also capable to predict the presence of lymph node metastases (Risk Chance ­ 1,006; CI-1.0001-1.00123; P =0.044). Taken together, our results sugest that CRT may represent a prognostic biomarker of PeCa. The strategy of integrated classic proteomic and MALDI Imaging revealed as usefull tool to search for news biomarkers of the disease. Futhermore, this work added an analytical perspective to the classical histopathology, allowing to include the techniques used in this project in future morphological studies, both in our institution and in the global context.


Subject(s)
Humans , Male , Adult , Middle Aged , Penile Neoplasms/chemistry , Carcinoma, Squamous Cell/chemistry , Proteins/analysis , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Papillomaviridae/isolation & purification , Papillomaviridae/genetics , Penile Neoplasms/virology , Carcinoma, Squamous Cell/virology , Biomarkers, Tumor , Serpins/analysis , Survival Analysis , Retrospective Studies , Calreticulin/analysis , Proteomics , 14-3-3 Proteins/analysis , Genotyping Techniques , Glutathione Transferase/analysis
4.
Recife; s.n; 2014. 73 p. ilus, mapas, tab.
Thesis in Portuguese | LILACS | ID: lil-720615

ABSTRACT

Em Cabo Verde, arquipélago situado na Costa Ocidental Africana, os primeiros casos de dengue ocorreram em 2009, com a notificação de mais de 21.000 casos, a maioria desses registrados na Ilha de Santiago. O mosquito Aedes aegypti foi identificado como vetor, e ações para seu controle, usando os inseticidas temephos (larvicida) e a deltametrina (adulticida), têm sido implementadas. Objetiva-se com esse trabalho avaliar o atual status de suscetibilidade a inseticidas e caracterizar os mecanismos de resistência nessa população. Amostras de A. aegypti da ilha de Santiago foram coletadas através de armadilhas de oviposição, para o estabelecimento de uma população a ser analisada. Foram realizados bioensaios do tipo dose diagnóstica, usando garrafas impregnadas com doses únicas dos adulticidas malathion (organofosforado), deltametrina (piretróide) e cipermetrina (piretróide), e bioensaios do tipo dose resposta, usando múltiplas concentrações dos inseticidas temephos (organofosforado), Bacillus thuringiensis sorovariedade israelensis (bactéria entomopatogênica) e diflubenzuron (inibidor de síntese de quitina). Para a investigação dos mecanismos de resistências, foram realizados testes bioquímicos com substratos específicos para quantificar a atividade das enzimas glutationa S-transferases, esterases (alfa, beta e PNPA) e oxidases de função mista, ligadas a detoxificação de xenobióticos, e a taxa de inibição da acetilcolinesterase ligada a insensibilidade do sítio alvo...


Cape Verde, an archipelago located on the West African Coast, recorded the first cases of dengue in 2009 in an epidemic with more than 21,000 reportedcases. The worst affected area was Santiago Island...


Subject(s)
Animals , Aedes , Enzymes/toxicity , Insect Vectors/virology , Insecticide Resistance , Africa, Western , Bacillus thuringiensis/pathogenicity , Esterases/analysis , Glutathione Transferase/analysis , Malathion/toxicity , Toxicity Tests , Temefos/toxicity
5.
Neotrop. ichthyol ; 10(3): 613-622, Sept. 2012. ilus
Article in English | LILACS | ID: lil-653600

ABSTRACT

Microcystins are secondary metabolites produced by different species of cyanobacteria, such as Microcystis aeruginosa (MA). In this study, the biochemical and genetic effects of lyophilized MA were evaluated in the neotropical fish Prochilodus lineatus exposed to 1 or 2 mg L-1 lyophilized MA (treated group) or only water (control group) in static toxicity tests for 24 and 96 h. The gills and liver were used in the analysis of biotransformation enzymes and antioxidant defenses, blood and gill cells in genetic analysis and in brain and muscle it was determined the activity of acetylcholinesterase (AChE). The results showed the biotransformation pathway activation due to the increase in hepatic CYP1A and in branchial and hepatic glutathione S-transferase (GST). The antioxidant defense proved to be greatly affected by MA exposure leading to changes, both in gills and liver, in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and in the content of tripeptide glutathione (GSH). Lipid peroxidation was not detected, but damage to DNA molecule was observed in blood cells. In conclusion, it can be state the lyophilized MA is able to promote changes in the biochemical and genetic parameters of P. lineatus.


As microcistinas são metabólitos secundários produzidos por diferentes espécies de cianobactérias, como a Microcystis aeruginosa (MA). Neste estudo, os efeitos bioquímicos e genéticos de liofilizado de MA foram avaliados para juvenis da espécie de peixe Neotropical Prochilodus lineatus expostos a 1 ou 2 mg L-1 de liofilizado de MA (grupo tratado) ou apenas à água (grupo controle), em testes de toxicidade estáticos, durante 24 e 96 h. As brânquias e o fígado foram usados para as análises das enzimas de biotransformação e defesas antioxidantes, células do sangue e das brânquias para análises genéticas e no cérebro e músculo foi determinada a atividade da acetilcolinesterase (AChE). Os resultados mostraram ativação da via de biotransformação devido ao aumento da atividade da CYP1A hepática e da atividade da glutationa S-transferase (GST) hepática e branquial. As defesas antioxidantes foram muito afetadas pela exposição a MA levando a alterações, tanto no fígado como nas brânquias, na atividade da superóxido dismutase (SOD), da catalase (CAT), da glutationa peroxidase (GPx), glutationa redutase (GR) e no conteúdo do tripeptídeo glutationa (GSH). Apesar dessas alterações a peroxidação lipídica não foi detectada em nenhum dos tecidos, mas danos na molécula de DNA foram observados nas células do sangue. Em conclusão, pode-se afirmar que o liofilizado de MA é capaz de promover alterações em parâmetros bioquímicos e genéticos de P. lineatus.


Subject(s)
Animals , Antioxidants/adverse effects , Biotransformation , Characiformes/genetics , Microcystis/enzymology , Acetylcholinesterase/analysis , Enzymes/analysis , Glutathione Transferase/analysis
6.
Rev. colomb. biotecnol ; 13(1): 66-72, jul. 2011. tab, graf, ilus
Article in Spanish | LILACS | ID: lil-600575

ABSTRACT

Las beta-glucosidasas son enzimas que poseen actividad hidrolitica y transferasa o transglucosidasa. Tienen diversas aplicaciones; en la biosintesis de oligosacaridos, produccion de etanol utilizando residuos agricolas y en la industria de vinos. La aplicacion industrial, sin embargo, requiere estabilidad a temperaturas elevadas, por lo que los microorganismos termofilos tienen gran interes. El proposito de esta investigacion es el de optimizar el medio de cultivo anaerobio de bacterias termofilas, para aumentar la produccion de beta-glucosidasas. Esta enzima es producida por tres aislados bacterianos: FT3, 2B y P5 los cuales fueron aislados de la region andina de Bolivia. El aislado bacteriano FT3 mostro una actividad beta-glucosidasa de 0,35 [UI/mL]. Se tomaron como variables dentro de la optimizacion del medio de cultivo las fuentes de nitrogeno y de carbono, y el pH. Asi tambien se probaron dos sistemas de cultivo: celulas libres y encapsuladas. Empleando extracto de levadura como fuente de nitrogeno se obtuvo una actividad de 0,52 [UI/mL]. En la optimizacion del pH del medio de cultivo se obtuvo una actividad de 0,81 [UI/mL] a pH 5. Como fuente de carbono se eligieron los hidrolizados de paja de trigo y paja de quinoa lleg¨¢ndose a obtener actividades de 1,27 y 1,34 [UI/mL] respectivamente. Se establecio que la localizacion celular de la enzima beta-glucosidasa es extracelular y presenta estabilidad hasta una temperatura de 80 ºC y un pH de 7.


The beta-glucosidases possess hydrolytic and transferase activity or transglucosidase. They have various applications; such as biosynthesis of oligosaccharides, production of ethanol using agricultural residues and wine industry. However for industrial application, stability to high temperatures is needed. Therefore a great interesting in the thermophile microorganism study exist. The purpose of this research is to optimize the culture medium of thermophilic anaerobic bacteria to increase the production of beta-glucosidase. This enzyme is produced by three isolate bacterial FT3, 2B and P5 which were isolated from the Andean region of Bolivia. FT3 isolate showed beta-glucosidase activity of 0.35 [IU/mL]. In regards to the optimization of culture medium variables such as nitrogen source, carbon source and pH were taken into account and also the combination with free and encapsulated bacterial cells. Yeast extract was the selected source of nitrogen obtaining an activity of 0.52 [IU/ mL]. The optimal pH was 5 obtaining an activity of 0.81 [IU/mL]. The selected carbon source was the hydrolyzed wheat straw and quinoa straw obtaining activities of 1.27 and 1.34 [IU/mL], respectively. The cellular localization of beta-glucosidase enzyme is extracellular and provides stability to temperature of 80 ºC and stability at pH 7.


Subject(s)
Glucosidases/analysis , Glucosidases/biosynthesis , Glutathione Transferase/analysis , Glutathione Transferase/biosynthesis , Glutathione Transferase/classification , Glutathione Transferase/pharmacology , Glutathione Transferase/chemistry , Glutathione Transferase/chemical synthesis , Glutathione Transferase/ultrastructure , Oligosaccharides/isolation & purification , Oligosaccharides/analysis , Oligosaccharides/genetics , Oligosaccharides/chemistry , Oligosaccharides/chemical synthesis , Oligosaccharides/ultrastructure , Oligosaccharides
7.
Medicina (B.Aires) ; 71(2): 139-145, mar.-abr. 2011. ilus, graf, tab
Article in English | LILACS | ID: lil-633833

ABSTRACT

The utilization of adenosine 5´-triphosphate (ATP ) infusions to inhibit the growth of some human and animals tumors was based on the anticancer activity observed in in vitro and in vivo experiments, but contradictory results make the use of ATP in clinical practice rather controversial. Moreover, there is no literature regarding the use of ATP infusions to treat hepatocarcinomas. The purpose of this study was to investigate whether ATP prevents in vivo oncogenesis in very-early-stage cancer cells in a well characterized two-stage model of hepatocarcinogenesis in the rat. As we could not preclude the possible effect due to the intrinsic properties of adenosine, a known tumorigenic product of ATP hydrolysis, the effect of the administration of adenosine was also studied. Animals were divided in groups: rats submitted to the two stage preneoplasia initiation/promotion model of hepatocarcinogenesis, rats treated with intraperitoneal ATP or adenosine during the two phases of the model and appropriate control groups. The number and volume of preneoplastic foci per liver identified by the expression of glutathione S-transferase placental type and the number of proliferating nuclear antigen positive cells significantly increased in ATP and adenosine treated groups. Taken together, these results indicate that in this preneoplastic liver model, ATP as well as adenosine disturb the balance between apoptosis and proliferation contributing to malignant transformation.


La utilización de adenosina 5´-trifosfato (ATP ) para inhibir el crecimiento de algunos tumores en humanos y en animales se basa en la actividad anticancerígena observada en experimentos in vitro e in vivo. El uso del ATP en la práctica clínica es discutido debido a resultados contradictorios. Por otra parte, no existen antecedentes del uso de ATP en el tratamiento de hepatocarcinomas. El objetivo del presente estudio fue determinar si el ATP previene la oncogénesis in vivo en un modelo de preneoplasia hepática murina de dos etapas. Para determinar la probable contribución de la adenosina, producto de la hidrólisis de ATP y descrita como tumorigénica, se estudió también el efecto del nucleósido exógeno sobre los focos preneoplásicos. Los animales se dividieron en grupos: ratas sometidas al modelo de preneoplasia de iniciación/promoción, ratas tratadas con ATP o adenosina intraperitonealmente durante las dos fases del modelo y los correspondientes grupos controles. El número y el volumen de focos preneoplásicos por hígado, identificados por la expresión de la forma placentaria de la glutation S- transferasa de rata y el número de células positivas para el antígeno nuclear proliferante, aumentaron significativamente en los grupos tratados con ATP y adenosina. Los resultados en su conjunto indican que en este modelo preneoplásico, el ATP y la adenosina alteran el balance entre apoptosis y proliferación, contribuyendo a la transformación maligna.


Subject(s)
Animals , Male , Rabbits , Rats , Adenosine Triphosphate/therapeutic use , Antineoplastic Agents/therapeutic use , Liver Neoplasms, Experimental/drug therapy , Precancerous Conditions/drug therapy , Precancerous Conditions/pathology , Cell Proliferation/drug effects , Drug Evaluation, Preclinical , Glutathione Transferase/analysis , Liver Neoplasms, Experimental/pathology , Liver/drug effects , Liver/enzymology , Rats, Wistar
8.
Braz. j. med. biol. res ; 43(3): 242-248, Mar. 2010. graf, tab
Article in English | LILACS | ID: lil-539721

ABSTRACT

The chemopreventive potential of water extracts of the Brassica vegetables cabbage and kale was evaluated by administering their aqueous extracts in drinking water ad libitum to Wistar rats submitted to Ito’s hepatocarcinogenesis model (CB group and K group, respectively - 14 rats per group). Animals submitted to this same model and treated with water were used as controls (W group - 15 rats). Treatment with the vegetable extracts did not inhibit (P > 0.05) placental glutathione S-transferase-positive preneoplastic lesions (PNL). The number of apoptotic bodies did not differ (P > 0.05) among the experimental groups. Ex vivo hydrogen peroxide treatment of rat livers resulted in lower (P < 0.05) DNA strand breakage in cabbage- (107.6 ± 7.8 µm) and kale- (110.8 ± 10.0 µm) treated animals compared with control (120.9 ± 12.7 µm), as evaluated by the single cell gel (comet) assay. Treatment with cabbage (2 ± 0.3 µg/g) or kale (4 ± 0.2 µg/g) resulted in increased (P < 0.05) hepatic lutein concentration compared with control (0.5 ± 0.07 µg/g). Despite the absence of inhibitory effects of cabbage and kale aqueous extracts on PNL, these Brassica vegetables presented protection against DNA damage, an effect possibly related to increased hepatic lutein concentrations. However, it must be pointed out that the cause-effect relationship between lutein levels and protection is hypothetical and remains to be demonstrated.


Subject(s)
Animals , Male , Rats , Antioxidants/pharmacology , Brassica/chemistry , DNA Damage , Liver Neoplasms, Experimental/prevention & control , Plant Extracts/pharmacology , Precancerous Conditions/prevention & control , Anticarcinogenic Agents/pharmacology , Apoptosis/drug effects , DNA , Glutathione Transferase/analysis , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/enzymology , Precancerous Conditions/chemically induced , Precancerous Conditions/enzymology , Rats, Wistar
9.
Salud pública Méx ; 49(4): 302-311, jul.-ago. 2007. tab, ilus
Article in Spanish | LILACS | ID: lil-458842

ABSTRACT

OBJETIVOS: Diagnosticar la resistencia a insecticidas y sus mecanismos en Anopheles albimanus del sur de la Península de Yucatán (PY), México. MATERIAL Y MÉTODOS: La F1 de An. albimanus colectados durante noviembre-diciembre de 2005 en seis localidades de los municipios Othón P. Blanco en Quintana Roo y Calakmul en Campeche, fue sometida a pruebas de susceptibilidad con deltametrina, DDT, pirimifos metil y bendiocarb, y a pruebas bioquímicas para calcular los niveles de las enzimas involucradas en la resistencia. RESULTADOS: An. albimanus fue resistente al DDT y a deltametrina en las seis localidades con niveles elevados de glutatión S-transferasas (GSTs), monooxigenasas y esterasas, y a pirimifos metil en La Unión con una alta frecuencia de la acetilcolinesterasa (AChE) alterada. CONCLUSION: Las poblaciones de An. albimanus colectadas al sur de la PY son resistentes al DDT y deltametrina, y en La Unión además al pirimifos metil, con mecanismos basados en la AChE alterada para el pirimifos metil, GST para DDT, y monooxigenasas y esterasas para piretroides. Los resultados del presente estudio tienen importantes consecuencias prácticas para el control químico de An. albimanus en el sur de la PY.


OBJECTIVE: To diagnose susceptibility levels and insecticide resistance mechanisms in Anopheles albimanus from the southern Yucatan Peninsula (YP), Mexico. MATERIAL AND METHODS: F1 generation of An. albimanus females, collected from November to December 2005 in six villages in the Othon P. Blanco municipality in Quintana Roo and the Calakmul municipality in Campeche, were exposed to deltamethrin, DDT, pirimiphos-methyl and bendiocarb in susceptibility tests, as well as to biochemical assays in order to calculate the enzyme levels related to insecticide resistance. RESULTS: High levels of DDT and deltamethrin resistance were found in An. albimanus collected from the six villages, and a high resistance to pirimiphos-methyl was found in those from La Union, Quintana Roo. Biochemical assays showed high levels of glutathione S-transferase (GST), cytochrome P450 and esterases (with pNPA substrate) in all villages. The frequency of An. albimanus with altered acetylcholinesterase (AChE) was high in La Union (33 percent). CONCLUSIONS: The An. albimanus populations collected in the south of the YP are resistant to DDT and deltamethrin, whereas resistance to pirimiphos-methyl was significant only in those collected from La Union. The mechanisms explaining this resistance are based on high concentrations of GST, cytochrome P450 and esterasas, the former being responsible for DDT metabolism and the others for pyrethroid metabolism. The altered AChE was the mechanism correlated to pirimiphos-methyl resistance in La Union. The results of the present study have important practical consequences for the chemical control of An. albimanus in the south of the YP.


Subject(s)
Animals , Female , Anopheles , Insecticides , Acetylcholinesterase/analysis , Anopheles/enzymology , /analysis , Data Interpretation, Statistical , DDT , Esterases/analysis , Glutathione Transferase/analysis , Insecticide Resistance/drug effects , Mexico , Mosquito Control , Nitriles , Organothiophosphorus Compounds , Pyrethrins , Seasons
10.
Indian J Exp Biol ; 2007 May; 45(5): 432-8
Article in English | IMSEAR | ID: sea-60515

ABSTRACT

The toxic effects of paraquat on the anti-oxidant defense system of male albino rats were evaluated, after administering either a single dose (1.5 and 7.5 mg/kg of body weight) or continuous daily doses (same as above, i.e., 1.5 mg/kg and 7.5 mg/kg of body weight) for 3 and 7 days. Glutathione levels in blood cells, liver, lung and kidney tissues decreased in a dose and time dependent manner. Glutathione reductase and glucose-6-phosphate dehydrogenase activity decreased, whereas the activity of glutathione-S-transferase, glutathione peroxidase, catalase and superoxide dismutase increased in paraquat exposure. Malondialdehyde formation also increased in a dose and time dependent manner. The alterations of anti-oxidant system particularly glutathione can be utilized as biomarkers during management of paraquat poisoning.


Subject(s)
Animals , Antioxidants/analysis , Catalase/analysis , Dose-Response Relationship, Drug , Erythrocytes/chemistry , Glucosephosphate Dehydrogenase/analysis , Glutathione/analysis , Glutathione Peroxidase/analysis , Glutathione Reductase/analysis , Glutathione Transferase/analysis , Kidney/chemistry , Lipid Peroxidation/drug effects , Liver/chemistry , Lung/chemistry , Male , Oxidative Stress/drug effects , Paraquat/toxicity , Rats , Rats, Wistar , Superoxide Dismutase/analysis
11.
J Environ Biol ; 2005 Oct; 26(4): 681-5
Article in English | IMSEAR | ID: sea-113183

ABSTRACT

Lipid oxidation is a process, which results in rancidity and deterioration of fats posing a major problem in food industry. Antioxidants are of interest, which presumably protects food from oxidative deterioration during storage. The glutathione antioxidant system of different meat samples were noticed for six months under refrigerated storage. Activity of glutathione reductase (GR) and level of glutathione (GSH) decreased during six months storage in all the four meat samples. The glutathione peroxidase (GSH-Px) and glutathione-S-transferase (GST) activity increased gradually during storage. It seems possible that glutathione antioxidant system protected the meat samples against quality loss during its storage.


Subject(s)
Animals , Antioxidants/analysis , Buffaloes , Chickens , Food Inspection , Frozen Foods/analysis , Glutathione/analysis , Glutathione Peroxidase/analysis , Glutathione Reductase/analysis , Glutathione Transferase/analysis , Goats , Meat/analysis , Sus scrofa
12.
Article in English | WPRIM | ID: wpr-119641

ABSTRACT

Effects of diets on hepatic aflatoxin B1 (AFB1)- DNA binding and AFB1-induced glutathione S- transferase placental (GST-P) form positive hepatic foci have been examined in young male Fischer rats. Animals were fed either AIN-76A or Purina Chow (PC) diet for 1 wk before AFB1- DNA binding studies in vivo and in vitro. Animals were injected i.p. with AFB1 (1 mg/kg body wt) and 3 days later were given either AIN-76A or PC diet with or without 0.1% phenobarbital (PB) in their drinking water. All animals were sacrificed 10 wks after AFB1 dosing for analysis of AFB1-induced GST-P positive hepatic foci by immunochemistry. Two h after i.p. injection of AFB1, hepatic AFB1-DNA binding in AIN-76A fed rats was twice as much as those in PC fed animals without affecting GSH levels. There was no significant effect of diet on either cytochrome P-450 content, GSH levels or microsomal cytochrome P-450 mediated AFB1-DNA binding to exogenous DNA. There was a 40% increase in cytosolic GSH S-transferase activity with 1-chloro-2,4-dinitrobenzene as a substrate in PC fed animals compared to those given AIN- 76A diet. The number and area of AFB1-induced GST-P positive hepatic foci were twice and fivefold as much in AIN-76A fed compared to those in PC fed rats. The number of AFB1-induced GST-P positive foci was increased 5-10 fold in the presence of PB in both groups. In summary, the present data indicate that feeding of PC diet compared to AIN-76A diet inhibits the initiation phase whereas AIN-76A stimulates the promotion phase of AFB1 hepatocarcinogenesis in rats by inhibiting AFB1-DNA binding and increasing AFB1-induced hepatic foci respectively.


Subject(s)
Aflatoxin B1/metabolism , Animals , Cell Transformation, Neoplastic , Cytochrome P-450 Enzyme System/metabolism , DNA/metabolism , Diet , Glutathione Transferase/analysis , Hepatocytes/drug effects , Liver Neoplasms/etiology , Microsomes, Liver/enzymology , Rats
13.
Genet. mol. res. (Online) ; 2(3): 295-308, Sept. 2003.
Article in English | LILACS | ID: lil-417600

ABSTRACT

The effects of crude extracts of the mushroom Agaricus blazei Murrill (Agaricaceae) on both DNA damage and placental form glutathione S-transferase (GST-P)-positive liver foci induced by diethylnitrosamine (DEN) were investigated. Six groups of adult male Wistar rats were used. For two weeks, animals of groups 3 to 6 were treated with three aqueous solutions of A. blazei (mean dry weight of solids being 1.2, 5.6, 11.5 and 11.5 mg/ml, respectively). After this period, groups 2 to 5 were given a single ip injection 200 mg/kg DEN and groups 1 and 6 were treated with 0.9 NaCl. All animals were subjected to 70 partial hepatectomy at week five and sacrificed 4, 24 and 48 h or 8 weeks after DEN or 0.9 NaCl treatments (10th week after the beginning of the experiment). The alkaline comet assay and GST-P-positive liver foci development were used to evaluate the influence of the mushroom extracts on liver cell DNA damage and on the initiation of liver carcinogenesis, respectively. Previous treatment with the highest concentration of A. blazei (11.5 mg/ml) significantly reduced DNA damage, indicating a protective effect against DEN-induced liver cytotoxicity/genotoxicity. However, the same dose of mushroom extract significantly increased the number of GST-P-positive liver foci


Subject(s)
Animals , Male , Agaricus/chemistry , Anticarcinogenic Agents/pharmacology , DNA Damage/drug effects , Glutathione Transferase/drug effects , Liver Neoplasms, Experimental/prevention & control , Carcinogens , Comet Assay , Diethylnitrosamine , Drug Screening Assays, Antitumor , Liver/drug effects , Liver/enzymology , Liver/pathology , Glutathione Transferase/analysis , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/enzymology , Rats , Rats, Wistar
14.
J Environ Biol ; 2002 Apr; 23(2): 157-62
Article in English | IMSEAR | ID: sea-113969

ABSTRACT

The present study was performed to investigate the toxic impact of carbaryl on biochemical metabolism in the hemolymph, brain, hepatopancreas, gills and muscle of intermoult juveniles of the economically important prawn, Macrobrachium malcolmsonii. The concentration of glutathione S-transferase (GST) was found to be higher in test prawns when compared with controls. This suggests that a mechanism of detoxification was in operation to neutralise carbaryl toxicity. However, the toxic effect of carbaryl was not fully neutralised, and hence, alterations were recorded in basic biochemical metabolism of test prawns. The concentration of acetylcholinestrase (AchE) was found to be lower in test prawns than that of controls. Carbaryl toxicity resulted in utilisation of major biochemical constituents, such as total carbohydrate, glycogen, protein and lipid to generate required energy as an attempt to withstand the toxic stress. Glycogenolysis resulted in elevation of total free sugar level in the hemolymph of test prawns. While proteolysis led to elevation of total free amino acid level in test prawns. The content of total lipid have also been found lower in test prawns than that of controls. This suggests that carbaryl toxicity resulted in severe energy crises in test prawns. In the present study, toxic effects of carbaryl impair basic metabolic functions and hence pose a threat to the life of M. malcolmsonii.


Subject(s)
Acetylcholinesterase/analysis , Amino Acids/metabolism , Animals , Brain/physiology , Carbaryl/adverse effects , Gills/physiology , Glutathione Transferase/analysis , Glycogen/metabolism , Hemolymph/metabolism , Insecticides/adverse effects , Lipid Metabolism , Palaemonidae/metabolism , Water Pollutants, Chemical/adverse effects
15.
Rev. cuba. med. trop ; 53(1): 32-36, ene.-abr. 2001. tab, graf
Article in Spanish | LILACS | ID: lil-327176

ABSTRACT

Se modificaron las técnicas de detección de la actividad de esterasas inespecíficas y de la glutation-s-transferasa, utilizadas en Culex quinquefasciatus, para su detección en Aedes aegypti (L.). Se determinaron para cada una de las enzimas, los valores de concentración óptima de sustrato (concentración saturante) y de tiempo óptimo de lectura de la reacción, mediante la utilización de 4 cepas de Aedes aegypti, 1 de Cuba, 2 de Venezuela y 1 cepa susceptible de referencia. La frecuencia de esterasas inespecíficas resultó ser en MIRANDA de 0,76 en ARAGUA 0,42 y en SANTIAGO DE CUBA se obtuvo el valor máximo de frecuencia de este mecanismo. Para el mecanismo de glutation-s-transferasa la frecuencia resultó ser de 0,45 en ARAGUA, 0,043 en MIRANDA y en SANTIAGO de CUBA de 1. Por primera vez en Cuba se pudo disponer de una batería de técnicas bioquímicas para la detección de los mecanismos de resistencia en Aedes aegypti, esto permitió conformar una base sólida para la detección rápida y temprana de la resistencia en esta especie, principal vector del dengue en las Américas


Subject(s)
Aedes , Esterases , Glutathione Transferase/analysis
16.
Article in English | IMSEAR | ID: sea-33532

ABSTRACT

Present status of insecticide resistance was investigated in two major vectors of malaria; An. culicifacies and An. subpictus, collected from a high malaria transmission area in Sri Lanka during 1996/1998. Adult and larval bioassays were carried out to obtain log-probit mortality lines for malathion, propoxur, permethrin and chlorpyrifos. Respective LD50 values were 4.45%, 0.002%, 0.16% and 0.001% for An. culicifacies and 0.66%, 0.004%, 0.004% and 0.04% for An. subpictus. Adults were also tested for WHO standard discriminating dosages of malathion, propoxur, permethrin, DDT, cypermethrin, deltamethlin and lambda cyhalothrin. Both populations were highly resistant to DDT. An. culicifacies was more resistant to malathion and An. subpictus was more resistant to chlorpyrifos. About 25% of both populations were resistant to permethrin. An. culicifacies was susceptible to propoxur, deltamethrin and lambda cyhalothrin and An. subpictus to cypermethrin and lambda cyhalothrin. Adult mosquitos were individually tested for their insecticide detoxifying enzyme activities and altered target-site, acetylcholinesterase. High general esterase activity indicated the presence of amplified esterase genes in both populations. Native gel electrophoresis resolved one elevated esterase isoenzyme, with high affinity to organophosphates, from each species. Malathion carboxylesterase mechanism was present in both populations. Higher glutathione-S-transferase activity was marked in An. subpictus. Synergistic studies showed the possible involvement of monooxygenases in resistance in both species. Acetylcholinesterase activity of approximately 80% of both populations was not inhibited by a standard dosage of propoxur. Low resistance to carbamates shows that the impact of agricultural pesticides is not significant in the development of resistance especially in An. culicifaies. Pyrethroids, other than permethrin, can be successfully used in vector control programs. Carbamates will be an alternative.


Subject(s)
Acetylcholinesterase/analysis , Animals , Anopheles/drug effects , Biological Assay , Chlorpyrifos/pharmacology , Electrophoresis, Polyacrylamide Gel , Glutathione Transferase/analysis , Insect Vectors , Insecticide Resistance , Insecticides/pharmacology , Malaria/prevention & control , Malathion/pharmacology , Mosquito Control , Permethrin , Propoxur/pharmacology , Pyrethrins/pharmacology , Regression Analysis , Sri Lanka
18.
Yonsei Medical Journal ; : 95-100, 1981.
Article in English | WPRIM | ID: wpr-225822

ABSTRACT

An experiment was conducted in order to investigate the effect of p-dimethylaminoazobenzene (DAB) and 2(3)-tert-butyl-4-hydroxyanisole (BHA) on the lipid peroxidation and peroxide-destroying enzyme system in the rat liver. Dietary supplementation of DAB (0.06%) for three weeks caused the elevation of glutathione-S-transferase activity by 60% and glutathione reductase by 50%, but it decreased glutathione peroxidase and catalase activities significantly. Dietary supplementation of BHA (0.75%) also increased glutatione-S-transferase activity in the liver by 2 folds, and it counteracts DAB effect on the glutathione peroxidase and catalase activities. There was a marked increase in malon-dialdehyde content in the postnuclear fraction of liver by the treatment of DAB, but the addition of BHA lowered the malondialdehyde content to almost the control level. The protective effect of BHA on the lipid peroxidation induced by DAB administration at the enzyme level seems to be due to the induction of glutathione-S-transferase and the protection of glutathione peroxidase and catalase activities from being lowered by DAB administration.


Subject(s)
Animals , Anisoles/pharmacology , Butylated Hydroxyanisole/pharmacology , Glutathione Peroxidase/analysis , Glutathione Reductase/analysis , Glutathione Transferase/analysis , Lipid Peroxides/metabolism , Liver/drug effects , Liver/metabolism , Male , Peroxidases/analysis , Rats , p-Dimethylaminoazobenzene/pharmacology
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