Browsing by Author "Araújo, Glaucy Rodrigues de"
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Item Annato extract and β-carotene modulate the production of reactive oxygen species/nitric oxide in neutrophils from diabetic rats.(2012) Rossoni Júnior, Joamyr Victor; Araújo, Glaucy Rodrigues de; Pádua, Bruno da Cruz; Chaves, Míriam Martins; Pedrosa, Maria Lúcia; Silva, Marcelo Eustáquio; Costa, Daniela CaldeiraAnnatto has been identified asecarotenoids that havetantioxidative 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.Item Aqueous extract of Baccharis trimera improves redox status and decreases the severity of alcoholic hepatotoxicity.(2017) Rabelo, Ana Carolina Silveira; Araújo, Glaucy Rodrigues de; Lúcio, Karine de Pádua; Araújo, Carolina Morais; Miranda, Pedro Henrique de Amorim; Silva, Breno de Mello; Carneiro, Ana Cláudia Alvarenga; Ribeiro, Erica Milena de Castro; Lima, Wanderson Geraldo de; Souza, Gustavo Henrique Bianco de; Brandão, Geraldo Célio; Costa, Daniela CaldeiraThe metabolism of ethanol occurs mainly in the liver, promoting increase of reactive oxygen species and nitrogen, leading to redox imbalance. Therefore, antioxidants can be seen as an alternative to reestablish the oxidizing/reducing equilibrium. The aim of this study was to evaluate the antioxidant and hepatoprotective effect of aqueous extract of Baccharis trimera (Less.) DC., Asteraceae, in a model of hepatotoxicity induced by ethanol. The extract was characterized and in vitro tests were conducted in HepG2 cells. It was evaluated the cells viability exposed to aqueous extract for 24 h, ability to scavenging the radical DPPH, besides the production of reactive oxygen species and nitric oxide, and the influence on the transcriptional activity of transcription factor Nrf2 (12 and 24 h) after exposure to 200 mM ethanol. The results showed that aqueous extract was non-cytotoxic in any concentration tested; moreover, it was observed a decrease in ROS and NO production, also promoting the transcriptional activity of Nrf2. In vivo, we pretreatment male rats Fisher with 600 mg/kg of aqueous extract and 1 h later 5 ml/kg of absolute ethanol was administrated. After two days of treatment, the animals were euthanized and lipid profile, hepatic and renal functions, antioxidant status and oxidative damage were evaluated. The treatment with extract improved liver function and lipid profile, reflecting the reduction of lipid microvesicules in the liver. It also promoted an increase of glutathione peroxidase activity, decrease of oxidative damage and MMP2 activity. These results, analyzed together, suggest the hepatoprotective effect of B. trimera aqueous extract.Item Baccharis trimera (Carqueja) Improves metabolic and redox status in an experimental model of type 1 diabetes.(2018) Kaut, Natália Nogueira do Nascimento; Rabelo, Ana Carolina Silveira; Araújo, Glaucy Rodrigues de; Taylor, Jason Guy; Silva, Marcelo Eustáquio; Pedrosa, Maria Lúcia; Chaves, Míriam Martins; Rossoni Júnior, Joamyr Victor; Costa, Daniela CaldeiraDiabetes mellitus is a metabolic disorder that causes severe complications due to the increased oxidative stress induced by disease. Many plants are popularly used in the treatment of diabetes, e.g., Baccharis trimera (carqueja). The aim of this study was to explore the potential application of the B. trimera hydroethanolic extract in preventing redox stress induced by diabetes and its hypoglycemic properties. Experiments were conducted with 48 female rats, divided into 6 groups, named C (control), C600 (control + extract 600 mg/kg), C1200 (control + extract 1200 mg/kg), D (diabetic), D600 (diabetic + 600 mg/kg), and D1200 (diabetic + 1200 mg/kg). Type 1 diabetes was induced with alloxan, and the animals presented hyperglycemia and reduction in insulin and body weight. After seven days of experimentation, the nontreated diabetic group showed changes in biochemical parameters (urea, triacylglycerol, alanine aminotransferase, and aspartate aminotransferase) and increased carbonyl protein levels. Regarding the antioxidant enzymes, an increase in superoxide dismutase activity was observed but in comparison a decrease in catalase and glutathione peroxidase activity was noted which suggests that diabetic rats suffered redox stress. In addition, the mRNA of superoxide dismutase, catalase, and glutathione peroxidase enzymes were altered. Treatment of diabetic rats with B. trimera extract resulted in an improved glycemic profile and liver function, decreased oxidative damage, and altered the expression of mRNA of the antioxidants enzymes. These results together suggest that B. trimera hydroethanolic extract has a protective effect against diabetes.Item Baccharis trimera inhibits reactive oxygen species production through PKC and down-regulation p47phox phosphorylation of NADPH oxidase in SK Hep-1 cells.(2017) Araújo, Glaucy Rodrigues de; Rabelo, Ana Carolina Silveira; Meira, Janaína Serenato; Rossoni Júnior, Joamyr Victor; Borges, William de Castro; Cota, Renata Guerra de Sá; Batista, Maurício Azevedo; Lemos, Denise da Silveira; Souza, Gustavo Henrique Bianco de; Brandão, Geraldo Célio; Chaves, Míriam Martins; Costa, Daniela CaldeiraBaccharis trimera, popularly known as ‘‘carqueja’’, is a native South-American plant possessing a high concentration of polyphenolic compounds and therefore high antioxidant potential. Despite the antioxidant potential described for B. trimera, there are no reports concerning the signaling pathways involved in this process. So, the aim of the present study was to assess the influence of B. trimera on the modulation of PKC signaling pathway and to characterize the effect of the nicotinamide adenine dinucleotide phosphate oxidase enzyme (NOX) on the generation of reactive oxygen species in SK Hep-1 cells. SK-Hep 1 cells were treated with B. trimera, quercetin, or rutin and then stimulated or notwith PMA/ionomycin and labeled with carboxy H2DCFDA for detection of reactive oxygen species by flow cytometer. The PKC expression by Western blot and enzyme activity was performed to evaluate the influence of B. trimera and quercetin on PKC signaling pathway. p47phox and p47phox phosphorylated expression was performed byWestern blot to evaluate the influence of B. trimera on p47phox phosphorylation. The results showed that cells stimulated with PMA/ionomycin (activators of PKC) showed significantly increased reactive oxygen species production, and this production returned to baseline levels after treatment with DPI (NOX inhibitor). Both B. trimera and quercetin modulated reactive oxygen species production through the inhibition of PKC protein expression and enzymatic activity, also with inhibition of p47phox phosphorylation. Taken together, these results suggest that B. trimera has a potentialmechanism for inhibiting reactive oxygen species production through the PKC signaling pathway and inhibition subunit p47phox phosphorylation of nicotinamide adenine dinucleotide phosphate oxidase.Item Baccharis trimera inibe a produção de espécies reativas de oxigênio através da via de sinalização da PKC e NADPH oxidase em células SK Hep-1.(2015) Araújo, Glaucy Rodrigues de; Costa, Daniela Caldeira; Chaves, Míriam MartinsBaccharis trimera, popularmente conhecida como "carqueja", é uma planta nativa sul-americana que possui uma alta concentração de compostos fenólicos e, portanto, alto potencial antioxidante. Apesar do potencial antioxidante de B. trimera descrito na literatura, não existem relatos sobre as vias de sinalização envolvidas neste processo. A enzima NADPH oxidase é uma fonte importante na produção de espécies reativas de oxigênio (ERO) em condições patológicas, como no câncer, no diabetes e em processos inflamatórios. Esta enzima é ativada por meio de diferentes moduladores, entre os quais destaca-se a proteína cinase C (PKC), que fosforila a subunidade p47phox da NADPH oxidase, como um contribuinte para a ativação do complexo enzimático e a consequente geração de ERO. Com base nestas informações, o objetivo do presente estudo foi avaliar a composição fitoquímica dos extratos aquoso e hidroetanólico de Baccharis trimera bem como a influência destes extratos na modulação de ERO e na via de sinalização da PKC e NADPH oxidase em células de hepatocarcinoma humano (SK Hep-1). No presente estudo, a quercetina e a rutina foram utilizadas como controles positivos, pois o efeito antioxidante destes flavonoides tem sido bem estabelecido, sendo estes compostos já identificados em extratos de B. trimera. No extrato hidroetanólico foram identificados cinco flavonoides enquanto no extrato aquoso foram identificados três flavonoides por CLAE-EM. A atividade antioxidante in vitro por DPPH também foi avaliada e os resultados demonstraram que o extrato hidroetanólico possui um maior potencial em sequestrar o radical DPPH bem como uma maior quantidade de compostos fenólicos em comparação ao extrato aquoso. Em relação à viabilidade celular, observamos que o extrato hidroetanólico de B. trimera manteve acima de 70% a porcentagem de células viáveis, entretanto em 24 e 48 horas de incubação houve uma redução da viabilidade (<70%) em concentrações iguais ou superiores a 25μgmL-1. Em relação ao extrato aquoso observamos que a porcentagem de células viáveis foi mantida acima de 70% em 12, 24 e 48 de incubação. Em relação a produção de espécies reativas foi observado que os extratos de B. trimera (aquoso e hidroetanólico) diminuíram os níveis de ERO em células SK Hep-1 não estimuladas. Níveis reduzidos de ERO também foram observados nas células tratadas com quercetina e rutina. Os resultados mostraram que as células estimuladas com PMA / ionomicina (ativadores de PKC) tiveram um aumento significativo na produção de ERO, e esta produção voltou aos níveis basais após tratamento com o DPI (inibidor da NADPH oxidase). O extrato hidroetanólico de B. trimera e quercetina, mas não o extrato aquoso e a rutina, modularam a produção de ERO através da inibição da expressão e atividade da proteína PKC e também através da redução da fosforilação da subunidade p47phox da enzima NADPH oxidase. Em conjunto, estes resultados sugerem um mecanismo potencial de ação de B. trimera na inibição da produção de ERO através da via de sinalização da PKC/NADPH oxidase.Item Baccharis trimera protects against ethanol induced hepatotoxicity in vitro and in vivo.(2018) Rabelo, Ana Carolina Silveira; Lúcio, Karine de Pádua; Araújo, Carolina Morais; Araújo, Glaucy Rodrigues de; Miranda, Pedro Henrique de Amorim; Carneiro, Ana Cláudia Alvarenga; Ribeiro, Erica Milena de Castro; Silva, Breno de Mello; Lima, Wanderson Geraldo de; Costa, Daniela CaldeiraEthnopharmacological relevance: Baccharis trimera has been traditionally used in Brazil to treat liver diseases. Aim of the study: To evaluate the protective effect of Baccharis trimera in an ethanol induced hepatotoxicity model. Materials and methods: The antioxidant capacity was evaluated in vitro by the ability to scavenged the DPPH radical, by the quantification of ROS, NO and the transcription factor Nrf2. Hepatotoxicity was induced in animals by administration of absolute ethanol for 2 days (acute) or with ethanol diluted for 28 days (chronic). The biochemical parameters of hepatic function (ALT and AST), renal function (urea and creatinine) and lipid profile (total cholesterol, triglycerides and HDL) were evaluated. In addition to antioxidant defense (SOD, catalase, glutathione), oxidative damage markers (TBARS and carbonylated protein), MMP-2 activity and liver histology. Results: Baccharis trimera promoted a decrease in ROS and NO, and at low concentrations promoted increased transcription of Nrf2. In the acute experiment it promoted increase of HDL, in the activity of SOD and GPx, besides diminishing TBARS and microesteatosis. Already in the chronic experiment B. trimera improved the hepatic and renal profile, decreased triglycerides and MMP-2 activity, in addition to diminishing microesteatosis. Conclusion: We believe that B. trimera action is possibly more associated with direct neutralizing effects or inhibition of reactive species production pathways rather than the modulation of the antioxidant enzymes activity. Thus it is possible to infer that the biological effects triggered by adaptive responses are complex and multifactorial depending on the dose, the time and the compounds used.Item Efeito antioxidante do captopril e a influência da via de sinalização de PKC na produção de EROS induzida por Bradicinina no modelo experimental de diabetes mellitus tipo 1.(Programa de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa e Pós Graduação, Universidade Federal de Ouro Preto., 2011) Araújo, Glaucy Rodrigues de; Costa, Daniela CaldeiraO diabetes é uma doença que acomete milhões de pessoas em todo o mundo e tem sido alvo de muitos estudos. As complicações no diabetes, como a cardiomiopatia e o estresse oxidativo aumentado são importantes focos de estudo e são responsáveis em grande parte pelo aumento na morbidade e mortalidade associado à doença. Drogas anti-hipertensivas, principalmente aquelas que bloqueiam o sistema renina-angiotensina, como o captopril, são utilizadas com freqüência para o tratamento de diabetes, contribuindo para minimizar as complicações diabéticas. A relação do diabetes e inflamação evidencia o importante papel dos mecanismos de defesa nessa patologia. Além disso, as vias de sinalização envolvidas no processo e ativação dos granulócitos no diabetes ainda não é bem esclarecida. Sabe-se que a via de proteína cinase C (PKC) tem um importante papel na ativação da NADPH oxidase nessas células. No presente estudo, utilizou-se ratas Fisher, não diabéticas ou diabéticas induzidas com estreptozotocina (STZ), para avaliar produção de espécies reativas de oxigênio (EROS) em granulócitos e parâmetros do estresse oxidativo no coração em um tratamento com duas doses de captopril (5mg/kg e 10mg/kg). Ainda foi avaliado a participação da via de (PKC) na produção de EROS induzido por bradicinina, em granulócitos de ratas Fisher não diabéticas e diabéticas. No primeiro ensaio in vivo, tratou-se os animais durante 10 dias, e nenhuma diferença foi observada na produção de EROS nos granulócitos desses animais. Um tratamento de 40 dias foi então realizado, onde avaliou-se a produção de EROS nos granulócitos e parâmetros do estresse oxidativo, como catalase, glutationa total, substâncias reativas ao ácido tiobarbitúrico (TBARS) e proteína carbonilada no coração destes animais. No tratamento de 40 dias, o captopril na dose 10mg/kg foi capaz de modular a produção de EROS nos granulócitos dos animais diabéticos. O captopril ainda foi capaz de reverter a atividade da enzima catalase e os níveis de proteína carbonilada no coração de animais diabéticos, apesar de não ter sido observado efeito significativo nos níveis de glutationa e TBARS. No ensaio in vitro os granulócitos de animais não diabéticos e diabéticos apresentaram uma maior produção de EROS quando estimulados com bradicinina. E somente nos animais diabéticos, houve a redução na produção de EROS quando os granulócitos foram pré-incubados com calfostim C (inibidor de PKC), mostrando a participação dessa via na ativação da produção de EROS induzido por bradicinina.Estes resultados analisados em conjunto sugerem que o captopril tem efeito antioxidante em granulócitos e no coração de animais diabéticos. Entretanto, parece que o efeito inibitório na produção de EROS em granulócitos de animais tratados com captopril (ensaio in vivo) não é mediado pela bradicinina (ensaio in vitro).Item Lycopene inhibits reactive oxygen species production in SK-Hep-1 cells and attenuates acetaminophen-induced liver injury in C57BL/6 mice.(2017) Bandeira, Ana Carla Balthar; Silva, Talita Prato da; Araújo, Glaucy Rodrigues de; Araújo, Carolina Morais; Silva, Rafaella Cecília da; Lima, Wanderson Geraldo de; Bezerra, Frank Silva; Costa, Daniela CaldeiraOur aim was to investigate the antioxidant potential of lycopene in different experimental liver models: in vitro, to evaluate the influence of lycopene on reactive oxygen species (ROS) production mediated by the PKC pathway and in vivo, to evaluate the protective effects of lycopene in an experimental model of hepatotoxicity. The in vitro study assessed the lycopene antioxidant potential by the quantification of ROS production in SK-Hep-1 cells unstimulated or stimulated by an activator of the PKC pathway. The role of NADPH oxidase was evaluated by measuring its inhibition potential using an inhibitor of this enzyme. In the in vivo study, male C57BL/6 mice received lycopene (10 or 100 mg/kg by oral gavage) and 1 h later, acetaminophen (APAP) (500 mg/kg) was administrated. Lycopene decreased ROS production in SK-Hep- 1 cells through inhibition of NADPH oxidase, brought about in the PKC pathway. Lycopene improved hepatotoxicity acting as an antioxidant, reduced GSSG and regulated tGSH and CAT levels, reduced oxidative damage primarily by decreasing protein carbonylation, promoted the downregulation of MMP- 2 and reduced areas of necrosis improving the general appearance of the lesion in C57BL/6 mice. Lycopene is a natural compound that was able to inhibit the production of ROS in vitro and mitigate the damage caused by APAP overdose in vivo.Item The antioxidant and anti-inflammatory properties of lycopene in mice lungs exposed to cigarette smoke.(2017) Campos, Keila Karine Duarte; Araújo, Glaucy Rodrigues de; Martins, Thais Lourenço; Bandeira, Ana Carla Balthar; Costa, Guilherme de Paula; Silva, André Talvani Pedrosa da; Garcia, Camila Carrião Machado; Oliveira, Laser Antônio Machado de; Costa, Daniela Caldeira; Bezerra, Frank SilvaLycopene is a carotenoid with knownantioxidant and anti-inflammatory properties.Weaimed to evaluate the in vitro and in vivo effects of lycopene on reducing the redox imbalance and inflammation induced by cigarette smoke (CS). For the in vitro study, J774A.1 (macrophages) cells were incubated in the presence of 0.5, 1.0, 2.0, 4.0, 8.0, 10.0 and 25 μMof lycopene for 3, 6 and 24 h or in the presence of 0.1%, 0.25%, 0.5%, 0.625%, 1.25%, 2.25%, 5% and 10% cigarette smoke extract (CSE) for 3, 6 and 24 h to assess cell viability and measurement of intracellular reactive oxygen species (ROS). For the in vivo study, 40 micewere divided into 5 groups: a control exposed to ambient air (CG), a vehicle-control group that received 200 μl of sunflower oil by orogastric gavage, a group exposed to CS and two groups administered lycopene (diluted in sunflower oil) at doses of either 25 or 50 mg/kg/day prior to exposure to CS (LY25+CS and LY50+CS). The total treatment time lasted 5 days. A cell viability decreasewas observed at 10- and 25-μMconcentrations of lycopene in 3, 6 and 24 h compared with CG. Therewas an increase ofROS production in 24 h in CS compared with CG. Lycopene concentrations of 1 μMand 2 μMwere able to reduce the production of ROS in 24 h comparedwith CS. In the bronchoalveolar lavage fluid, the total number of leukocytes increased in the CS group compared with the control groups (CG). Administrationwith lycopene at the highest dose suppressed this CS-induced increase in leukocytes. Lipid peroxidation and DNA damage increased in the CS group comparedwith that in the controls, and this increase was suppressed by lycopene at the highest dose. In contrast, superoxide dismutase activity decreased in the CS group compared with that in the controls. Catalase activity also increased in the CS group compared with that in both control groups, and this increase was suppressed in LY25+CS and LY50+CS. There was an increase in the levels of tumor necrosis factor-α, interferon-γ and interleukin-10 after exposure to CS, and these effects were suppressed by both doses of lycopene. These data elucidate the role of lycopene as an antioxidant and anti-inflammatory agent in these two models of short-term exposure to CS.Item Vildagliptin ameliorates oxidative stress and pancreatic beta cell destruction in type 1 diabetic rats.(2013) Ávila, Danielle de Lima; Araújo, Glaucy Rodrigues de; Silva, Maísa; Miranda, Pedro Henrique de Amorim; Diniz, Mirla Fiuza; Pedrosa, Maria Lúcia; Silva, Marcelo Eustáquio; Lima, Wanderson Geraldo de; Costa, Daniela CaldeiraBackground and Aims. It is believed that oxidative stress plays a role in the pathogenesis of diabetes mellitus. Several strategies have been developed with the objective of minimizing diabetic complications. Among these, inhibitors of dipeptidyl peptidase-IV (DPP-IV), which act by blocking degradation of incretin hormones, glucagon-like peptide hormone (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), have been the focus of many studies. It is known that, among the effects of incretins, we highlight its insulinotropic and cytoprotective effects on pancreatic b-cells. The objective of this study was to evaluate the possible protective effects of treatment with vildagliptin, a DPP-IV inhibitor, in b-cells in an experimental model of type 1 diabetes induced by streptozotocin (STZ). Methods. Rats were treated for 4 weeks with vildagliptin at concentrations of 5 and 10 mg/kg. In order to observe the pancreatic damage and the possible protective effects of vildagliptin treatment, we measured stress markers TBARS and protein carbonyl, antioxidant enzymes SOD and catalase, and analyzed pancreatic histology. Results. The treatment was effective in modulating stress in pancreatic tissue, both by reducing levels of stress markers as well as by increasing activity of SOD and catalase. After analyzing the pancreatic histology, we found that vildagliptin was also able to preserve islets and pancreatic b-cells, especially at the concentration of 5 mg/kg. Conclusion. Thus, our results suggest that vildagliptin ameliorates oxidative stress and pancreatic beta cell destruction in type 1 diabetic rats. However, to evaluate the real potential of this medication in type 1 diabetes, further studies are needed.