13 research outputs found
Comparison of Brazilian Plants Used to Treat Gastritis on the Oxidative Burst of Helicobacter pylori
Ten Brazilian medicinal plants used to treat gastritis and ulcers were carefully selected on the basis of ethnopharmacological importance and antiulcerogenic activity previously described. The antioxidant activity of the methanolic extracts was determined in analysis conditions that simulate a real biological activity on inhibition of the oxidative burst induced in neutrophils using Helicobacter pylori as activator, by a luminol-amplified chemiluminescence assay. The extracts, at low concentration (5 μg/mL), exhibited a large variation in inhibitory effects of H. pylori-induced oxidative burst ranging from 48% inhibition to inactive, but all extracts, excluding Byrsonima intermedia, had inhibitory activity over 80% at the concentration of 100 μg/mL. The total suppressive antioxidant capacity measured as the effective concentration, which represents the extract concentration producing 50% inhibition of the chemiluminescence induced by H. pylori, varies from 27.2 to 56.8 μg/mL and was in the following order: Qualea parviflora > Qualea multiflora > Alchornea triplinervia > Qualea grandiflora > Anacardium humile > Davilla elliptica > Mouriri pusa > Byrsonima basiloba > Alchornea glandulosa > Byrsonima intermedia. The main groups of compounds in tested extracts are presented. Differences in the phytochemical profile, quantitatively and qualitatively, of these plants can explain and justify their protective effect on the gastric mucosa caused by the neutrophil-generated ROS that occurs when H. pylori displays its evasion mechanisms
Effect of Byrsonima crassa and Phenolic Constituents on Helicobacter pylori-Induced Neutrophils Oxidative Burst
Byrsonima crassa Niedenzu (Malpighiaceae) is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric ulcers. In a previous study, our group described the gastric protective effect of the methanolic extract from the leaves of B. crassa. The present study was carried out to investigate the effects of methanolic extract and its phenolic compounds on the respiratory burst of neutrophils stimulated by H. pylori using a luminol-based chemiluminescence assay as well as their anti-H. pylori activity. The suppressive activity on oxidative burst of H. pylori-stimulated neutrophils was in the order of methyl gallate > (+)-catechin > methanol extract > quercetin 3-O-α-l-arabinopyranoside > quercetin 3-O-β-d-galactopyranoside > amentoflavone. Methyl gallate, compound that induced the highest suppressive activity with IC50 value of 3.4 μg/mL, did not show anti-H. pylori activity. B. crassa could be considered as a potential source of natural antioxidant in gastric ulcers by attenuating the effects on the damage to gastric mucosa caused by neutrophil generated reactive oxygen species, even when H. pylori displays its evasion mechanisms
Anti-Helicobacter pylori activity and oxidative burst inhibition by the naphthoquinone 5-methoxy-3,4-dehydroxanthomegnin from Paepalanthus latipes
Anti-Helicobacter pylori activity and immunostimulatory effect of extracts from Byrsonima crassa Nied. (Malpighiaceae)
<p>Abstract</p> <p>Background</p> <p>Several <it>in vitro </it>studies have looked at the effect of medicinal plant extracts against <it>Helicobacter pylori </it>(<it>H. pylori</it>). Regardless of the popular use of <it>Byrsonima crassa </it>(<it>B. crassa</it>) as antiemetic, diuretic, febrifuge, to treat diarrhea, gastritis and ulcers, there is no data on its effects against <it>H. pylori</it>. In this study, we evaluated the anti-<it>H. pylori </it>of <it>B. crassa </it>leaves extracts and its effects on reactive oxygen/nitrogen intermediates induction by murine peritoneal macrophages.</p> <p>Methods</p> <p>The minimal inhibitory concentration (MIC) was determined by broth microdilution method and the production of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) and nitric oxide (NO) by the horseradish peroxidase-dependent oxidation of phenol red and Griess reaction, respectively.</p> <p>Results</p> <p>The methanolic (MeOH) and chloroformic (CHCl<sub>3</sub>) extracts inhibit, <it>in vitro</it>, the growth of <it>H. pylori </it>with MIC value of 1024 μg/ml. The MeOH extract induced the production H<sub>2</sub>O<sub>2 </sub>and NO, but CHCl<sub>3 </sub>extract only NO.</p> <p>Conclusion</p> <p>Based in our results, <it>B. crassa </it>can be considered a source of compounds with anti-<it>H. pylori </it>activity, but its use should be done with caution in treatment of the gastritis and peptic ulcers, since the reactive oxygen/nitrogen intermediates are involved in the pathogenesis of gastric mucosal injury induced by ulcerogenic agents and <it>H. pylori </it>infections.</p
Effect of Byrsonima crassa and Phenolic Constituents on Helicobacter pylori-Induced Neutrophils Oxidative Burst
Byrsonima crassa Niedenzu (Malpighiaceae) is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric ulcers. In a previous study, our group described the gastric protective effect of the methanolic extract from the leaves of B. crassa. The present study was carried out to investigate the effects of methanolic extract and its phenolic compounds on the respiratory burst of neutrophils stimulated by H. pylori using a luminol-based chemiluminescence assay as well as their anti-H. pylori activity. The suppressive activity on oxidative burst of H. pylori-stimulated neutrophils was in the order of methyl gallate > (+)-catechin > methanol extract > quercetin 3-O-α-l-arabinopyranoside > quercetin 3-O-β-d-galactopyranoside > amentoflavone. Methyl gallate, compound that induced the highest suppressive activity with IC50 value of 3.4 µg/mL, did not show anti-H. pylori activity. B. crassa could be considered as a potential source of natural antioxidant in gastric ulcers by attenuating the effects on the damage to gastric mucosa caused by neutrophil generated reactive oxygen species, even when H. pylori displays its evasion mechanisms
Atividade anti-Helicobacter pylori e potencial antioxidante de espécies vegetais do Cerrado brasileiro
Helicobacter pylori é, atualmente, reconhecido como o principal fator de risco para desenvolvimento da gastrite crônica e úlcera péptica. A resposta inflamatória decorrente da infecção por essa bactéria induz alterações patológicas no microambiente gástrico, com a liberação de citocinas e de grande quantidade de espécies reativas de oxigênio (EROs) por células inflamatórias, especialmente neutrófilos, que contribuem para a injúria da mucosa e desenvolvimento de câncer gástrico. Neste trabalho, a citotoxicidade basal, atividade anti-H. pylori e antioxidante de extratos (apolares e polares), frações, mistura de triterpenos (- amirina e -amirina) e compostos fenólicos (amentoflavona, (+)-catequina, galato de metila, quercetina-3-O--L-arabinopiranosídeo e quercetina-3-O--D-galactopiranosídeo) obtidos de plantas do Cerrado brasileiro, empregadas popularmente no tratamento de distúrbios gastrintestinais, foram determinadas pela técnica do vermelho neutro, microdiluição em caldo, redução do radical 1,1-difenil-2-picril-hidrazila (DPPH) e quimiluminescência dependente de luminol, respectivamente. As preparações vegetais (extratos, frações e mistura de triterpenos) apresentaram baixo potencial citotóxico para a linhagem celular empregada (McCoy). Dentre os compostos fenólicos, quercetina (padrão comercial) e (+)-catequina apresentaram maior citotoxicidade quando comparadas aos extratos, frações e mistura de triterpenos. As espécies Byrsonima crassa (Malpighiaceae) e Davilla elliptica (Dilleniaceae) demonstraram maior potencial para o tratamento de doenças induzidas pelo H. pylori por proporcionarem maior atividade antibacteriana (concentração mínima inibitória = 1024 g/mL), entretanto frações enriquecidas e substâncias isoladas não foram conclusivas para o reconhecimento de grupos ou compostos que pudessem inferir a mesma capacidade...Helicobacter pylori is a bacterium recognized as the major cause of chronic gastritis and peptic ulcer. The H. pylori infection induces an inflammatory response and pathological changes in the gastric microenvironment. The host immune cells (especially neutrophils) release inflammatory mediators and large amounts of reactive oxygen species (ROS), which are related to an increased risk of developing gastric cancer. In this study, we evaluated the basal cytotoxicity, anti-H. pylori and antioxidant activities of extracts (apolar and polar), fractions, mixture of triterpenes (-amirin and -amirin) and phenolic compounds (amentoflavone, (+)-catechin, methyl gallate, quercetin 3-O--L-arabinopyranoside and quercetin-3-O--D-galactopyranoside) obtained from Brazilian Cerrado plants used to treat gastrointestinal disorders, by neutral red uptake assay, broth microdilution method, 1,1- diphenyl-2-picrylhydrazyl (DPPH) radical and luminol-dependent chemiluminescence assays, respectively. A low basal cytotoxicity was showed by the vegetal preparations (extracts, fractions and mixture of triterpenes). Among the phenolic compounds tested, quercetin (commercial standard) and (+)-catechin demonstrated higher cytotoxicity as compared to extracts, fractions and mixture of triterpenes. The Byrsonima crassa (Malpighiaceae) and Davilla elliptica (Dilleniaceae) specie presented greater potential for the treatment of H. pylori-induced gastric pathologies, since they have better antibacterial activity (minimum inhibitory concentration = 1024 g/mL). However, fractions and isolated compounds were not conclusive to identify substances that could be accountable for the antimicrobial activity of the extracts. The antioxidant activity in vitro (DPPH assay) was not necessarily the same as those observed in the ex vivo assay (luminol-dependent chemiluminescence). Although the poor anti-H. pylori activity... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Anti-Helicobacter pylori activity and oxidative burst inhibition by the naphthoquinone 5-methoxy-3,4-dehydroxanthomegnin from Paepalanthus latipes
Helicobacter pylori is a bacterium recognized as the major cause of chronic gastritis and peptic ulcers. Infection by H. pylori induces inflammatory responses and pathological changes in the gastric microenvironment. The host Keywords: immune cells (especially neutrophils) release inflammatory mediators and large 5-methoxy-3,4-dehydroxanthomegnin amounts of reactive oxygen species (ROS), which are associated with an increased Helicobacter pyloririsk of developing gastric cancer. In this study, we evaluated the anti-H. pylori and oxidative burst antioxidantactivitiesofa1,4-naphthoquinone-5-methoxy-3,4-dehydroxanthomegnin. Paepalanthus latipes The antimicrobial activity was assessed using a spectrophotometric microdilution technique, and antioxidant activity was assessed by noting the effect of 5-methoxy3,4-dehydroxanthomegnin on the neutrophil oxidative burst using luminol-and lucigenin-amplified chemiluminescence. The results showed that 5-methoxy-3,4dehydroxanthomegnin is a potent anti-H. pylori compound (MIC 64 µg/mL and MBC 128 µg/mL) and a strong antioxidant. 5-Methoxy-3,4-dehydroxanthomegnin decreased luminol- and lucigenin-amplified chemiluminescence, with ED50 values of 1.58±0.09 µg/mL and 5.4±0.15 µg/mL, respectively, reflecting an inhibitory effect on the oxidative burst. These results indicate that 5-methoxy-3,4-dehydroxanthomegnin is a promising compound for the prevention and treatment of diseases caused by H. pylori infection, such as gastritis, peptic ulceration, and gastric cancer, because reactive oxygen intermediates are involved in the pathogenesis of gastric mucosal injury induced by H. pylori infections.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Relación entre el saneamiento básico y la incidencia de enteroparasitosis en Sinop, MT
Introduction: Protozoa and helminths cause enteroparasitoses, which constitute an important public health issue. Preschoolers and school children, who do not have a fully developed immune system, are more vulnerable to contamination by intestinal parasites because they are more exposed to risk factors, such as poor hygiene habits and crowding in closed places. The most common parasites affecting this age group include Giardia lamblia, Ascaris lumbricoides, Trichuris trichiura, and hookworms. Objectives: To evaluate the prevalence of intestinal parasites in preschoolers, school children, sandboxes of government schools in the city of Sinop – state of Mato Grosso (MT). Methods: This cross sectional, quantitative study with an experimental design was carried out from July 2015 to September 2016 and included preschoolers and school children aged 3 to 12 years, chosen by convenience sampling from government schools in the school district of the city of Sinop – MT; four schools were in the central region of Sinop, whereas seven schools, attended by children living in the suburban and rural areas, were far from the city center. Fecal samples were collected by the children’s family and sent to the schools, from where they were transported to the laboratory for parasitological examination. Sand samples were collected from sandboxes in the play areas of the schools. More specifically,100 g of sand was collected by scraping one of the four quadrants or the center of the sandbox surface or deeper into the sandbox, totaling 10 samples/box. The parasitological methods spontaneous sedimentation described by Hoffmann, active migration described by Rugai, centrifugal-spontaneous flotation described by Faust, and spontaneous flotation described by Willis were used to analyze the fecal and sand samples. Results: A total of 646 fecal samples obtained from preschoolers and school children aged 3 to 12 years were evaluated; 21.05% of the samples tested positive for intestinal parasites. As for the sand samples, 100% tested positive for intestinal parasites. In all the fecal and sand samples that tested positive for intestinal parasites, G. lamblia predominated, followed by Toxacara sp, Toxoplasma gondii, A. lumbricoides, Enterobius vermicularis, Hymenolepis nana, Strongyloides stercoralis, hookworm, and commensal amoebae of the large intestine, were also identified. Conclusion: Children aged 6 to 12 years were the most affected by enteroparasitoses. This may be related to poor hygiene habits, which puts these children at greater risk of contamination. The results agree with most epidemiological studies conducted in Brazil and show a high prevalence enteroparasitoses in children.Introdução: As enteroparasitoses são causadas por protozoários e helmintos e representam um importante problema de saúde pública. As crianças em idade pré-escolar e escolar apresentam maior vulnerabilidade à contaminação por enteroparasitas pelo fato de estarem mais expostas a fatores de risco, tais como hábitos precários de higiene e aglomeração em locais fechados, e por não apresentarem o sistema imunológico totalmente desenvolvido. Objetivos: Avaliar a prevalência de enteroparasitos em crianças pré-escolares e escolares e em caixas de areia de instituições públicas de ensino no município de Sinop-MT. Métodos: O tipo de estudo realizado foi transversal, quantitativo com delineamento experimental. Foi realizado no período de julho de 2015 a setembro de 2016. Foram avaliadas crianças pré-escolares e escolares de 3 a 12 anos escolhidas por amostragem de conveniência de quatro instituições da rede municipal de ensino localizadas na região central de Sinop – MT e sete afastadas do centro da cidade e que atendem novos bairros e a zona rural. As amostras de fezes foram coletadas pelos responsáveis das crianças que encaminharam para as instituições de ensino e, posteriormente, foram transportadas ao laboratório para realização do exame parasitológico. As amostras de areia foram coletadas a partir de caixas das áreas de recreações de todas as instituições de ensino, sendo coletada 100 gramas de areia da raspagem superficial e profunda dos quatro quadrantes e do centro, totalizando 10 amostras/caixa. Os métodos parasitológicos utilizados para análises das amostras de fezes e areia foram Hoffmann, migração ativa, centrífugo-flutuação espontânea por Faust e flutuação espontânea por Willis. Resultados: Foram avaliadas 646 amostras de fezes de crianças pré-escolares e escolares de 3 a 12 anos, apresentando 21,05% de positividade para parasitos intestinais. As 80 amostras de areia das caixas das áreas de recreação infantil avaliadas, apresentaram 100% de positividade para enteroparasitos, sendo G. lamblia mais prevalente, seguida de Toxocara sp, Toxoplasma gondii, A. lumbricoides e Strongyloides stercoralis. Conclusão: A faixa etária mais acometida foi verificada entre as crianças de 6 a 12 anos e pode estar relacionada aos precários hábitos de higiene e assim, maior risco de contaminação. Pode-se concluir que os resultados estão de acordo com a maioria dos estudos epidemiológicos realizados no Brasil, demonstrando elevada prevalência de enteroparasitoses em crianças em idade escolar.Las enteroparasitosis se encuentran entre las enfermedades más comunes en el mundo, siendo más frecuentes en niños menores de 12 años, constituyendo así un importante problema de salud pública. Se evaluaron 646 muestras de heces de niños en edad preescolar y escolar de 3 a ≥ 12 años, mostrando positividad para parásitos intestinales en 136 y 100% en muestras de arena de cajas en áreas de juego infantil. De las muestras positivas de heces y arena para enteroparásitos, Giardia lamblia mostró mayor positividad, seguida de Toxacara sp, Toxoplasma gondii, Ascaris lumbricoides, Enterobius vermicularis, Hymenolepis nana, Strongyloides stercoralis y anquilostomas. Las amebas comensales del intestino grueso identificadas fueron Entamoeba coli, Endolimax nana y Entamoeba hartmanni. La mayor positividad para Giardia lamblia se puede atribuir a fallas en la infraestructura de saneamiento básico en la ciudad de Sinop - MT, contaminación de la arena en las áreas de recreación y consumo de vegetales contaminados. El grupo de edad más afectado se encontró entre los niños de 3 a 9 años y puede estar relacionado con malos hábitos de higiene y, por tanto, mayor riesgo de contaminación. Se puede concluir que nuestros resultados están en línea con la mayoría de los estudios epidemiológicos realizados en Brasil, que muestran una alta incidencia de enteroparasitosis en niños, debido a las bajas condiciones socioeconómicas, los malos hábitos de higiene personal y las fallas en las condiciones básicas de saneamiento y suministro. de agua en Sinop - MT
Effect of subinhibitory concentration of chlorhexidine on Streptococcus agalactiae virulence factor expression
The aim of the present study was to investigate the effect of chlorhexidine at subinhibitory concentration (50% minimal inhibitory concentration (MIC)) on the growth, cytolysin expression and phagocytosis of Streptococcus agalactiae ATCC 13813. Bacterial growth with and without chlorhexidine treatment was monitored by turbidity measurements, and exocytolysins were estimated by neutral red uptake assay by the McCoy cell line. The phagocytic process was evaluated using luminol-enhanced chemiluminescence to follow the respiratory burst of polymorphonuclear neutrophils exposed to bacteria. Chlorhexidine-treated culture did not exhibit a detectable decrease in cell growth, and no statistically significant reduction in the respiratory burst of polymorphonuclear neutrophils was observed. However, growth in the presence of chlorhexidine resulted in a significant reduction of S. agalactiae exocytolysins. Although 50% MIC of chlorhexidine did not interfere with S. agalactiae growth and phagocytosis, the knowledge that this concentration was still able to alter some bacterial virulence parameters may be useful in its therapeutic applications. (c) 2006 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved
Relative antioxidant activity of Brazilian medicinal plants for gastrointestinal diseases
The free radical scavenging capacity of Brazilian medicinal plants and some of their constituents was examined in vitro using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) quantitative assay. Twelve medicinal plants, used to treat gastrointestinal disorders (Alchornea glandulosa, Alchornea triplinervia, Anacardium humile, Byrsonima crassa, Byrsonima cinera, Byrsonima intermedia, Davilla elliptica, Davilla nitida, Mouriri pusa, Qualea grandiflora, Qualea parviflora and Qualea multiflora), were selected because they showed antiulcerogenic activity in previous studies. The radical scavenging methanolic extracts activity demonstrated to be dose-dependent. The efficient concentration, which represents the amount of the antioxidant able of decrease the initial DPPH radical by 50%, vary from < 5 to 17.2 mu g/ml. The lowest efficient concentration values among the analyzed plant were shown by A. humile, B. crassa and Q. parviflora. Purified phenolic compounds (amentoflavone, (+)-catechin, methyl gallate, quercetin 3-O-alpha-L-arabinopyranoside, and quercetin 3-O-beta-D-galactopyranoside) were also tested and the greatest antioxidant activities were obtained with (+)-catechin and methyl gallate, similar to quercetin, a phenolic compound used as standard.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq