Bruno da Cruz Pádua

Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil

Are you Bruno da Cruz Pádua?

Claim your profile

Publications (7)15.74 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Acetaminophen is a common analgesic and antipyretic compound which, when administered in high doses, has been associated with significant morbidity and mortality, secondary to hepatic toxicity. Although this may be due to a direct interaction of reactive acetaminophen metabolites with hepatocyte proteins, recent studies have suggested that reactive species produced by neutrophils also contribute to the pathophysiological process. Researches on the chemical composition of B. trimera show that this plant has bioactive compounds such as flavonoids, related to the organism's protection against free radicals. Therefore, in the present study, using Fischer rats, the effect of B. trimera on the antioxidant defense system, the production of nitric oxide (NO) and on the expression of nitric oxide synthase (iNOS), superoxide dismutase (SOD), catalase (CAT) and of the subunits of the NADPH oxidase in neutrophils was evaluated in a model of phagocytosis induced by zimosan (ZC3b) and in a model of inflammation induced by acetaminophen. The results show that the treatment with B. trimera improves the defense system of antioxidant and restores the balance ROS / NO that is altered in the inflammatory process induced by APAP. In conclusion, B. trimera extracts exert antioxidant properties by scavenging ROS and decrease the expression of genes responsible by reactive species production in neutrophils.
    Current pharmaceutical biotechnology 12/2013; · 3.40 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: OBJECTIVE: Chagas heart disease is developed as a result of the infection with Trypanosoma cruzi. Protein malnutrition contributes to secondary immunodeficiency. The aim of this study was to investigate the role of a low protein diet on the production of endothelin-1 and CX3CL1 in blood and cardiac tissue samples in an experimental model with T. cruzi infection. METHODS: Fisher rats were submitted to low protein (6%) and normal protein (15%) diets and then infected with the Y strain of T. cruzi. At days 15 and 120, parasites and immune cells were evaluated. RESULTS: The low protein diet reduced body weight and circulating serum proteins, but promoted elevation of CX3CL1 and endothelin-1 levels in infected animals, which were unable to control blood parasitemia replication. In heart tissue, the low protein diet reduced cardiac CX3CL1, endothelin-1 and leucocyte infiltration in the acute phase, in particular CD68 and CD163 macrophage phenotypes. CONCLUSION: Together, these results highlight the participation of endothelin-1 and CX3CL1 in the inflammatory process of Chagas diesease, both being mediators partially controlled by the host nutritional status.
    Tropical Medicine & International Health 02/2013; · 2.94 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Annatto has been identified as carotenoids that have antioxidative effects. It is well known that one of the key elements in the development of diabetic complications is oxidative stress. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen species and reactive nitrogen species as part of the body's defense mechanisms to destroy invading pathogens. Reactive oxygen species/reactive nitrogen species are excessively produced by active peripheral neutrophils, and may damage essential cellular components, which in turn can cause vascular complications in diabetes. The present study was undertaken to evaluate the possible protective effects of annatto on the reactive oxygen species and nitric oxide (NO) inhibition in neutrophils from alloxan-induced diabetic rats. Adult female rats were divided into six groups based on receiving either a standard diet with or without supplementation of annatto extract or beta carotene. All animals were sacrificed 30 days after treatment and the neutrophils were isolated using two gradients of different densities. The reactive oxygen species and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Our results show that neutrophils from diabetic animals produce significantly more reactive oxygen species and NO than their respective controls and that supplementation with beta carotene and annatto is able to modulate the production of these species. Annatto extract may have therapeutic potential for modulation of the balance reactive oxygen species/NO induced by diabetes.
    Journal of Clinical Biochemistry and Nutrition 05/2012; 50(3):177-83. · 2.25 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Annatto (Bixa orellana L.) contains a mixture of orange-yellowish pigments due to the presence of various carotenoids that have antioxidant effect. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen and nitrogen species (ROS and RNS) as part of the body's defence mechanisms to destroy invading pathogens. It is well known that the function of neutrophils is altered in diabetes; one of the major functional changes in neutrophils in diabetes is the increased generation of extracellular superoxide via the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system. The purpose of this study is to evaluate the production of ROS and nitric oxide (NO) as well as the expression of NADPH oxidase subunits, inducible nitric oxide (iNOS), superoxide dismutase (SOD) and catalase (CAT) in neutrophils from diabetic rats treated with annatto extract and β-carotene. Forty-eight female Fisher rats were distributed into six groups according to the treatment received. All animals were sacrificed 7 days after treatment, and the neutrophils were isolated using two gradients of different densities. The ROS and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Analyses of gene expression were performed using quantitative real time polymerase chain reaction (qRT-PCR). The results show that treatment with annatto extract and β-carotene was able to decrease ROS production and the mRNA levels of p22(phox) and p47(phox) and increase the mRNA levels of SOD and CAT in neutrophils from diabetic rats. These data suggest that annatto extract and β-carotene exerts antioxidant effect via inhibition of expression of the NADPH oxidase subunits and increase expression/activity of antioxidant enzymes.
    Free Radical Research 03/2012; 46(3):329-38. · 3.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to investigate the possible effects of captopril as a promoter in modulating the oxidant-antioxidant balance in rats with type 1 diabetes, and the influence of protein kinase C (PKC) pathways in the production of reactive oxygen species (ROS) induced by bradykinin in type 1 diabetic rats. This study evaluated the redox status in both the cardiac tissue and at the cellular level (neutrophils). Two concentrations of captopril were utilized: (i) 5 mg·(kg body mass)-1, which was considered a therapeutic dose; and (ii) 10 mg·(kg body mass)-1. Body mass, plasma glucose, and serum insulin were evaluated. To investigate the redox status of the cardiac tissue, we analyzed lipid peroxidation, concentration of carbonylated protein, catalase activity, and the concentration of glutathione. For a more accurate assessment of the possible antioxidant effect of captopril, we also analyzed ROS in neutrophils (in vivo), and ROS production induced by bradykinin and the influence of the PKC pathway in this production (in vitro). Our data show that the hearts of diabetic animals have increased oxidative damage, exemplified by the increased concentration of carbonylated protein and thiobarbituric acid reactive substances (TBARS). However, animals treated with captopril at both concentrations showed lower concentrations of carbonylated protein compared with untreated diabetic animals. We found an increase of catalase activity in the heart of diabetic rats, which was reversed by captopril treatment at both of the dosages tested. Our data showed that captopril was able to reduce ROS production in the neutrophils of diabetic rats at a dose of 10 mg captopril·(kg body mass)-1. However, the antioxidant effect of captopril is independent of bradykinin. Diabetes induces oxidative stress, and these results suggest that captopril has an antioxidant effect and can modulate the production of ROS in circulating neutrophils.
    Canadian Journal of Physiology and Pharmacology 12/2011; 89(12):923-933. · 1.56 Impact Factor
  • Bruno da Cruz Pádua
    [Show abstract] [Hide abstract]
    ABSTRACT: Baccharis trimera (Asteraceae) é uma planta amplamente distribuída na América do Sul e conhecida popularmente como carqueja. Muitas atividades biológicas têm sido atribuídas a diversas preparações desta espécie: analgésica, hepatoprotetora, antiinflamatória e antioxidante. Pesquisas da composição química de B. trimera demonstraram que este vegetal possui componentes bioativos como os triterpenos, relatados como os principais responsáveis pela atividade antiinflamatória da planta e os flavonóides, relacionados à proteção do organismo contra os radicais livres. No presente estudo, utilizando-se ratos Fischer machos, avaliamos, em um modelo de fagocitose, o efeito de B. trimera sobre a produção de espécies reativas de oxigênio (EROs) em neutrófilos e, em um modelo de inflamação, o efeito de B. trimera tanto sobre a produção de óxido nítrico e de EROs, quanto sobre as defesas antioxidantes e as concentração de biomarcadores do estresse oxidativo. A toxicidade dos tratamentos foi avaliada pelas atividades de transaminases e creatinina, marcadores da função hepática e renal, respectivamente, e por análises histológicas. No ensaio in vitro, neutrófilos de ratos machos foram isolados e incubados com extrato de B. trimera na concentração de 0,5 μg/mL, 5 μg/mL e 50 μg/mL, enquanto que no ensaio in vivo os ratos foram tratados com 600 mg/kg de B. trimera e 24h depois com 835 mg/Kg de acetaminofen (APAP). O extrato reduziu a produção de espécies reativas de oxigênio em neutrófilos tanto nos modelos experimentais in vitro quanto in vivo, além disso, análise dos níveis das substâncias reativas ao ácido tiobarbitúrico (TBAR), em outro modelo metodológico, indicou que os animais tratados com B.trimera e em seguida intoxicados com APAP apresentaram níveis de TBAR inferiores aos dos animais que receberam somente APAP. Esses dados associados à redução na concentração de NO em ratos tratados com o extrato de carqueja e posteriormente intoxicados com acetaminofen são fortes indícios que confirmam o real efeito antioxidante atribuído à B. trimera. Apesar desses efeitos, análises bioquímicas e histológicas indicaram que B. trimera não foi eficiente em reverter os danos hepáticos provocados pelo APAP. Baccharis trimera (Asteraceae), is a widely spread plant in South America and popularly known as carqueja. Many biological activities have been attributed to many preparations using this species: analgesic, hepatoprotective, anti-inflammatory and antioxidizing. Researches on the chemical composition of B. trimera show that this plant has bioactive compounds such as triterpenes, reported as the main responsible for the anti-inflammatory activity of the plant and flavonoids, related to the organisms protection against free radicals. In the present study, using male Fischer rats, the effect of B.trimera on the production of reactive oxygen species (ROS) in neutrophils was evaluated in a phagocytosis model; and in an inflammation model, the effect of B. trimera on the production of nitric oxide and ROS, as well as on the anti-oxidizing defenses and the concentration of oxidative stress biomarkers. The toxicity of treatments was evaluated through hepatic and kidney function. In the in vitro essay, neutrophils of male rats were isolated and incubated in B. trimera extract in the concentrations of 0,5 μg/mL, 5 μg/mL e 50 μg/mL, whereas in the in vivo essay the rats were treated with 600 mg/kg of B. trimera and 24 hours later with 835 mg/Kg of acetaminophen (APAP). The extract reduced the production of reactive oxygen species in neutrophils in the in vitro experimental model as well as in the in vivo model. In addition, analysis of the levels of substances reactive to tiobarbituric acid (TBAR) indicated that the animals treated with B. trimera and next intoxicated with APAP presented TBAR levels lower than the animals which received only APAP. These data associated with a reduction in the concentration of NO in rats treated with the extract of B. trimera and then intoxicated with acetaminophen are strong indicators which confirm the real anti-oxidizing effect attributed to B. trimera. Despite these effects, biochemical and histological analyses indicated that B.trimera was not efficient in reversing the hepatic damages caused by APAP.
    01/2011;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Baccharis trimera (Less.) (Asteraceae) is a native plant of Brazil. Also known as "carqueja", it has been popularly used to treat liver diseases, diabetes, as well as digestive disorders. Other studies have described the hepatoprotective, antioxidant and anti-inflammatory activities of the species. The aim of the present study was to investigate the antioxidant properties of Baccharis trimera in the neutrophils of Fisher rats in both in vitro and in vivo experimental models. In the in vitro assay, the neutrophils of male rats were isolated and incubated with Baccharis trimera extract at concentrations of 0.5, 5.0 and 50.0 microg/mL. In the in vivo assay, male rats were first treated with crude extract 600 mg/kg body weight of Baccharis trimera or with 50 mg/kg body weight of quercetin (reference substance) and then treated with 835 mg/kg of acetaminophen (APAP) after 24 h. The hydroethanolic extract of Baccharis trimera reduced the release of reactive oxygen species in the neutrophils in both the in vitro and in vivo experimental models. Therefore confirming its antioxidant effect. The results of this study confirm the antioxidant effect of Baccharis trimera.
    Journal of ethnopharmacology 06/2010; 129(3):381-6. · 2.32 Impact Factor