Navegando por Autor "Rossoni Júnior, Joamyr Victor"
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Item Agaricus brasiliensis (sun mushroom) affects the expression of genes related to cholesterol homeostasis.(2016) Miranda, Aline Mayrink de; Rossoni Júnior, Joamyr Victor; Silva, Lorena Souza e; Santos, Rinaldo Cardoso dos; Silva, Marcelo Eustáquio; Pedrosa, Maria LúciaPurpose The sun mushroom (Agaricus brasiliensis) is considered a major source of bioactive compounds with potential health benefits. Mushrooms typically act as lipidlowering agents; however, little is known about the mechanisms of action of A. brasiliensis in biological systems. This study aimed to determine the underlying mechanism involved in the cholesterol-lowering effect of A. brasiliensis through the assessment of fecal and serum lipid profiles in addition to gene expression analysis of specific transcription factors, enzymes, and transporters involved in cholesterol homeostasis. Methods Twenty-four albino Fischer rats approximately 90 days old, with an average weight of 205 g, were divided into four groups of 6 each and fed a standard AIN-93 M diet (C), hypercholesterolemic diet (H), hypercholesterolemic diet +1 % A. brasiliensis (HAb), or hypercholesterolemic diet +0.008 % simvastatin (HS) for 6 weeks. Simvastatin was used as a positive control, as it is a typical drug prescribed for lipid disorders. Subsequently, blood, liver, and feces samples were collected for lipid profile and quantitative real-time polymerase chain reaction gene expression analyses. Results Diet supplementation with A. brasiliensis significantly improved serum lipid profiles, comparable to the effect observed for simvastatin. In addition, A. brasiliensis dietary supplementation markedly promoted fecal cholesterol excretion. Increased expression of 7α-hydroxylase (CYP7A1), ATP-binding cassette subfamily G-transporters (ABCG5/G8), and low-density lipoprotein receptor (LDLR) was observed following A. brasiliensis administration. Conclusions Our results suggest that consumption of A. brasiliensis improves the serum lipid profile in hypercholesterolemic rats by modulating the expression of key genes involved in hepatic cholesterol metabolism.Item Alteration in cellular viability, pro-inflammatory cytokines and nitric oxide production in nephrotoxicity generation by Amphotericin B : involvement of PKA pathway signaling.(2013) França, Flávia Dayrell; Ferreira, Andrea da Fonseca; Lara, R. C.; Rossoni Júnior, Joamyr Victor; Costa, Daniela Caldeira; Moraes, Karen Cristiane Martinez de; Tagliati, Carlos Alberto; Chaves, Míriam MartinsAmphotericin B is one of the most effective antifungal agents; however, its use is often limited owing to adverse effects, especially nephrotoxicity. The purpose of this study was to evaluate the effect of inhibiting the PKA signaling pathway in nephrotoxicity using Amphotericin B from the assessment of cell viability, pro-inflammatory cytokines and nitric oxide (NO) production in LLC-PK1 and MDCK cell lines. Amphotericin B proved to be cytotoxic for both cell lines, as assessed by the mitochondrial enzyme activity (MTT) assay; caused DNA fragmentation, determined by flow cytometry using the propidium iodide (PI) dye; and activated the PKA pathway (western blot assay). In MDCK cells, the inhibition of the PKA signaling pathway (using the H89 inhibitor) caused a significant reduction in DNA fragmentation. In both cells lines the production of interleukin-6 (IL)-6 proved to be a dependent PKA pathway, whereas tumor necrosis factor-alpha (TNF-α) was not influenced by the inhibition of the PKA pathway. The NO production was increased when cells were pre-incubated with H89 followed by Amphotericin B, and this production produced a dependent PKA pathway in LLC-PK1 and MDCK cells lines. Therefore, considering the present study’s results as a whole, it can be concluded that the inhibition of the PKA signaling pathway can aid in reducing the degree of nephrotoxicity caused by Amphotericin B.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 Antioxidant properties of Baccharis trimera in the neutrophils of Fisher rats.(2010) Pádua, Bruno da Cruz; Silva, Lucas Dornela; Rossoni Júnior, Joamyr Victor; Humberto, Jorge Luiz; Chaves, Míriam Martins; Silva, Marcelo Eustáquio; Pedrosa, Maria Lúcia; Costa, Daniela CaldeiraEthnopharmacological relevance: 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. Aim of the study: 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. Material and methods: 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_g/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. Results: 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. Conclusion: The results of this study confirm the antioxidant effect of Baccharis trimera.Item Avaliação dos efeitos do extrato de Baccharis trimera (carqueja) sobre parâmetros metabólicos e de estresse oxidativo em modelo de diabetes melito tipo 1 induzido por aloxano em ratas.(Programa de Pós-Graduação em Saúde e Nutrição. Escola de Nutrição, Universidade Federal de Ouro Preto., 2013) Kaut, Natália Nogueira do Nascimento; Costa, Daniela Caldeira; Rossoni Júnior, Joamyr VictorO diabetes mellitus tipo 1 é uma doença caracterizada pela destruição das células beta pancreáticas com consequente deficiência na secreção da insulina, resultando em hiperglicemia. As complicações do diabetes são onerosas para a saúde pública e de prejuízos irreparáveis para o portador da doença, pois abrange aspectos clínicos e sociais. Uma das causas das complicações do diabetes é o aumento do estresse oxidativo, situação na qual há um desequilíbrio entre as espécies reativas e as defesas antixidantes. Em busca de terapias alternativas, diversas plantas têm sido popularmente utilizadas no tratamento do diabetes. A planta medicinal Baccharis trimera, popularmente conhecida como carqueja, merece destaque dentre essas plantas, pois apresenta promissor potencial antioxidante e hipoglicemiante. Este estudo teve por objetivo avaliar os efeitos do extrato hidroetanólico da Baccharis trimera sobre os parâmetros metabólicos e de estresse oxidativo em modelo experimental de diabetes mellitus tipo 1 induzido por aloxano em ratas. Foi realizado experimento com 48 ratas da linhagem Fischer, divididas em 6 grupos, a saber: C (controle), C600 (controle + 600 mg/kg de extrato), C1200 (controle + 1200 mg/kg de extrato), D (diabéticos), D600 (diabéticos + 600 mg/kg); D1200 (diabéticos + 1200 mg/kg). As ratas tiveram o diabetes induzido por Aloxano, e após a confirmação do diabetes, todos os animais foram tratados por sete dias. Ao término do tratamento, as ratas foram eutanasiadas e tiveram o sangue coletado para realização das dosagens dos marcadores bioquímicos de perfil lipídico, função hepática e renal, e o fígado coletado para dosagem dos marcadores de estresse oxidativo (substâncias reativas ao ácido tiobarbitúrico e proteína carbonilada), dosagem das enzimas antioxidantes (superoxido dismutase, catalase, glutationa peroxidase e redutase), e análise da expressão do RNAm das enzimas antioxidantes. Os resultados obtidos mostraram que sete dias de diabetes são suficientes para alterar os marcadores bioquímicos, mas não são suficientes para alterar os marcadores de estresse oxidativo no fígado. As enzimas antioxidantes mostraram que os animais diabéticos apresentam quadro de estresse oxidativo visto que as ratas diabéticas apresentaram uma maior atividade da enzima superoxido dismutase e diminuição da atividade das enzimas catalase e glutationa peroxidase. A carqueja não mostrou efeito em diminuir a glicemia dos animais diabéticos, tampouco em modular o estresse oxidativo destes animais.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 improves the antioxidant defense system and inhibits iNOS and NADPH oxidase expression in a rat model of inflammation.(2013) Pádua, Bruno da Cruz; Rossoni Júnior, Joamyr Victor; Magalhães, Cíntia Lopes de Brito; Seibert, Janaína Brandão; Araújo, Carolina Morais; Souza, Gustavo Henrique Bianco de; Chaves, Míriam Martins; Silva, Marcelo Eustáquio; Pedrosa, Maria Lúcia; Costa, Daniela CaldeiraAcetaminophen 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.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 Cyclic adenosine monophosphate protects renal cell lines against amphotericin B toxicity in a PKA-independent manner.(2015) Ferreira, Andrea da Fonseca; França, Flávia Dayrell; Rossoni Júnior, Joamyr Victor; Moraes, Karen Cristiane Martinez de; Gomes, Dawidson Assis; Costa, Daniela Caldeira; Tagliati, Carlos Alberto; Chaves, Míriam MartinsAmphotericin B is the ‘‘gold standard’’ agent in the management of serious systemic fungal infections. However, this drug can cause nephrotoxicity, which contributes up to 25% of all acute kidney injuries in critically ill patients. Cyclic adenosine monophosphate can protect kidney cells from death due to injury or drug exposure in some cases. Hence, the objective of this work was to evaluate if cAMP could prevent cell death that occurs in renal cell lines subjected to AmB treatment and, if so, to assess the involvement of PKA in the transduction of this signal. Two different renal cell lines (LLC-PK1 and MDCK) were used in this study. MTT and flow cytometry assays showed increased cell survival when cells were exposed to cAMP in a PKA-independent manner, which was confirmed by western blot. This finding suggests that cAMP (db-cAMP) may prevent cell death caused by exposure to AmB. This is the first time this effect has been identified when renal cells are exposed to AmB’s nephrotoxic potential.Item Effect of an aqueous extract of annatto (Bixa orellana) seeds on lipid profile and biochemical markers of renal and hepatic function in hipercholesterolemic rats.(2009) Paula, Heberth de; Pedrosa, Maria Lúcia; Rossoni Júnior, Joamyr Victor; Haraguchi, Fabiano Kenji; Santos, Rinaldo Cardoso dos; Silva, Marcelo EustáquioAnnatto extract is a natural food color obtained from the outer coatings of the seeds of the Annatto tree (Bixa orellana L.). This is the first report in the literature that shows the relationship between the aqueous annatto extract and its influence on lipid profile in animals. Male Fisher rats were divided into three groups (n=12): C group, fed standard diet and water; H group, fed high-lipid diet and water and; HU group, with high-lipid diet and aqueous annatto extract for 60 days. The treatment with annatto extract in animals fed with the high-lipid diet lowered the LDL- and total cholesterol and raised the HDL-cholesterol, suggesting a hypocholesterolemic effect. Neither highfat diet nor aqueous annatto extract had any significant effect on serum levels of albumin or serum activities of transaminases which suggested that no liver injury was induced.Item Estudos preliminares da citoxicidade e propriedades fotoprotetoras de derivados de Benzofenonas e Lactonas.(2018) Gonçalves, Marlucy da Cruz; Taylor, Jason Guy; Rossoni Júnior, Joamyr Victor; Rabelo, Ana Carolina Silveira; Costa, Daniela Caldeira; Cazati, Thiago; Santos, Viviane Martins Rebello dosA Radiação solar ultravioleta(RUV) pode induzir efeitos à pele devidos a sua ação direta ou indireta, por meio da geração de radicais livres. Esses efeitos podem provocar diversas lesões na pele humana como o câncer de pele. Como medida de proteção da pele contra os efeitos da radiação solar pode-se citar o uso de protetores solares, produtos tópicos adicionados de filtros solares UV sintéticos com propriedades de absorção e reflexão de raios solares.Um fotoprotetor orgânico ideal deve proteger a pele contra os raios UVB (290-320 nm) e UVA (320-400 nm), possuir um fator de proteção solar (FPS) seguro, ser fotoestável e não ser fototóxico. Este trabalho objetiva em estudos preliminares de fotoproteção dos derivados das Benzofenonas e Lactonas. Os produtos obtidos foram sintetizados e caracterizados por técnicas espectroscópicas usuais e foram submetidos a ensaios de viabilidade celular frente ao MTT e determinação do valor de proteção solar (FPS) in vitro pelo método espectrofotométrico UV/VIS. Os espectros de IV, RMN de 1 H e RMN de 13C mostraram bandas e sinais em conformidades com as estruturas propostas para os compostos estudados. Os compostos 1 e2 apresentaram um FPS proporcional à concentração analisada, ou seja, quanto maior a concentração, maior é o Fator de Proteção, porém o composto 3 apresentou fator proteção menor em concentrações mais elevadas. No estudo de viabilidade celular, os compostos 1 e 2 não foram citotóxicos nas concentrações avaliadas neste trabalho.Item Extrato de urucum e β-caroteno alteram a sinalização redox em neutrófilos de ratas diabéticas através da regulação da expressão gênica da NADPH oxidase, superóxido dismutase e catalase.(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) Rossoni Júnior, Joamyr Victor; Silva, Marcelo Eustáquio; Costa, Daniela CaldeiraUrucum (Bixa orellana L.) contém uma mistura de pigmentos amarelo-avermelhado devido à presença de vários carotenóides que possuem efeito antioxidante. É bem estabelecido que um dos elementos chave no desenvolvimento das complicações do diabetes é o estresse oxidativo. O sistema imunológico é vulnerável a danos oxidativos, porque algumas células desse sistema, tais como neutrófilos, produzem espécies reativas de oxigênio (EROs) e espécies reativas de nitrogênio (ERNs) como parte dos mecanismos de defesa do organismo para destruir os patógenos invasores. EROs/ERNs são produzidos excessivamente por neutrófilos podendo danificar componentes celulares essenciais e dessa forma causar as complicações vasculares no diabetes. Esse estudo avaliou os possíveis efeitos protetores do extrato de urucum sobre as EROs, óxido nítrico (NO) e sobre os mecanismos regulatórios envolvidos neste processo em neutrófilos de ratas diabéticas induzidas por aloxano. Foram feitos dois experimentos, com duração de 30 ou 7 dias, e em cada foram utilizados 48 ratas que foram divididas em seis grupos, a saber: controle (C), controle + extrato de urucum (CUr), controle + β-caroteno (Cβcar), diabético (D), diabético + extrato de urucum (DUr) e diabético + β-caroteno (Dβcar). O diabetes foi induzido com uma injeção intraperitoneal única de aloxano (150 mg/Kg). Os animais dos grupos C e D receberam dieta padrão (AIN-93M) e os grupos CUr, Cβcar, DUr e Dβcar receberam dieta padrão suplementada com 0,1% de extrato de urucum ou β-caroteno. Todos os animais foram sacrificados 30 ou 7 dias depois do início do tratamento e os neutrófilos foram isolados usando dois gradientes de densidade diferentes. As EROs e NO foram quantificados por ensaios de quimioluminescência ou espectrofotometria, respectivamente. No experimento de 30 dias, nossos resultados mostraram que os neutrófilos de animais diabéticos produziram significativamente mais EROs e NO do que seus respectivos controle e a suplementação com extrato de urucum ou β-caroteno foi capaz de modular a produção dessas espécies reativas. No experimento de 7 dias, os resultados mostraram que o tratamento com extrato de urucum ou β-caroteno foi capaz de diminuir a produção de EROs, os níveis de mRNA de p22phox e p47phox e aumentar a expressão do mRNA e a atividade de SOD e catalase em neutrófilos de ratas diabéticas. Esses resultados sugerem que o extrato de urucum e o β-caroteno possuem efeito antioxidante via inibição das subunidades da NADPH oxidase e aumento da atividade e expressão das enzimas antioxidantes. O extrato de urucum pode ter um potencial terapêutico na modulação do balanço EROs/NO induzidos pelo diabetes.Item Lycopene pretreatment improves hepatotoxicity induced by acetaminophen in C57BL/6 mice.(2017) Bandeira, Ana Carla Balthar; Silva, Rafaella Cecília da; Rossoni Júnior, Joamyr Victor; Figueiredo, Vivian Paulino; Silva, André Talvani Pedrosa da; Cangussú, Silvia Dantas; Bezerra, Frank Silva; Costa, Daniela CaldeiraAcetaminophen (APAP) is an antipyretic and analgesic drug that, in high doses, leads to severe liver injury and potentially death. Oxidative stress is an important event in APAP overdose. Researchers are looking for natural antioxidants with the potential to mitigate the harmful effects of reactive oxygen species in different models. Lycopene has been widely studied for its antioxidant properties. The aim of this study was to evaluate the antioxidant potential of lycopene pretreatment in APAP-induced liver injury in C57BL/6 mice. C57BL/6 male mice were divided into the following groups: control (C); sunflower oil (CO); acetaminophen 500 mg/kg (APAP); acetaminophen 500 mg/kg + lycopene 10 mg/kg (APAP + L10), and acetaminophen 500 mg/kg + lycopene 100 mg/kg (APAP + L100). Mice were pretreated with lycopene for 14 consecutive days prior to APAP overdose. Analyses of blood serum and livers were performed. Lycopene was able to improve redox imbalance, decrease thiobarbituric acid reactive species level, and increase CAT and GSH levels. In addition, it decreased the IL-1b expression and the activity of MMP-2. This study revealed that preventive lycopene consumption in C57BL/6 mice can attenuate the effects of APAP-induced liver injury. Furthermore, by improving the redox state, and thus indicating its potential antioxidant effect, lycopene was also shown to have an influence on inflammatory events.Item Perfil lipídico, defesas antioxidantes e marcadores de função hepática e renal em hamsteres tratados com extratos de sementes de urucum.(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., 2008) Rossoni Júnior, Joamyr Victor; Silva, Marcelo EustáquioO urucum (Bixa orellana L.) tem sido descrito pela comunidade científica por seu efeito hipocolesterolemiante. Dessa forma o objetivo desse trabalho foi avaliar o efeito da infusão aquosa do urucum (Bixa orellana L) e da torta de bixina sobre o perfil lipídico, defesas antioxidantes e marcadores de função hepática e renal em hamsteres. Foram utilizados 64 hamsteres machos Golden Syrian que foram distribuídos em oito grupos: controle (C) recebeu dieta padrão (AIN-93 M), H recebeu dieta hipercolesterolemiante, CCh recebeu dieta padrão e infusão aquosa de urucum, HCh recebeu dieta hipercolesterolemiante e infusão aquosa de urucum, CB15 recebeu dieta padrão contendo 0,015% de torta de bixina, HB15 recebeu dieta hipercolesterolemiante contendo 0,015% de torta de bixina, CB75 recebeu dieta padrão contendo 0,075% de torta de bixina e HB75 recebeu dieta hipercolesterolemiante contendo 0,075% de torta de bixina. Amostras de sangue foram coletadas após oito semanas de experimento para realização as dosagens bioquímicas. Nos grupos hipercolesterolemiantes tratados com bixina, mas não nos que receberam dieta padrão tratados com bixina observamos um aumento dos níveis séricos de colesterol total, colesterol não-HDL, da fração HDL do colesterol, do colesterol hepático e da porcentagem de gordura nas fezes. Observamos uma diminuição dos triacilgliceróis nos grupos CB15, CB75 e HB75. A atividade da aspartato aminotransferase foi diminuída nos grupos que receberam dieta hipercolesterolemiante contendo 0,015% e 0,075% de torta de bixina. O tratamento com a torta de bixina aumentou atividade da ALP nos grupos CB15, HB15 e HB75 e na concentração de creatinina nos grupos CCh, CB15, CB75 e HB75. A atividade da paraoxonase apresentou-se diminuída nos grupos CCh, CB15 e CB75. A concentração de sulfidrilas ligadas a fração protéica aumentou 50% nos grupos CB15 e CB75 e uma diminuição de 30% nos grupos HB15 e HB75. A atividade da catalase aumentou nos grupos CB15 e HB15 e a atividade da paraoxonase apresentou-se diminuída nos grupos CCh, CB15 e CB75. Nossos dados indicam que no modelo experimental proposto e na concentração utilizada de torta de bixina houve um aumento na concentração sérica do colesterol nos grupos hipercolesterolemiantes não corroborando, dessa forma com os dados encontrados na literatura. Não observamos efeito protetor hepático e renal da torta de bixina nos hamsteres.Item Physical activity prevents alterations in mitochondrial ultrastructure and glucometabolic parameters in a high-sugar diet model.(2017) Queiroz, Karina Barbosa de; Sampaio, Kinulpe Honorato; Rossoni Júnior, Joamyr Victor; Leal, Diego Andrade; Pinto, Angélica Barbosa Gonçalves; Oliveira, Lenice Kappes Becker; Evangelista, Elísio Alberto; Cota, Renata Guerra de SáEndurance exercise is a remarkable intervention for the treatment of many diseases. Mitochondrial changes on skeletal muscle are likely important for many of the benefits provided by exercise. In this study, we aimed to evaluate the effects that a regular physical activity (swimming without workload) has on mitochondrial morphological alterations and glucometabolic parameters induced by a high-sugar diet (HSD). Weaned male Wistar rats fed with a standard diet or a HSD (68% carbohydrate) were subjected to 60 minutes of regular physical activity by swimming (without workload) for four- (20 sessions) or eight-week (40 sessions) periods. After training, animals were euthanized and the sera, adipose tissues, and skeletal muscles were collected for further analysis. The HSD increased body weight after an 8- week period; it also increased the fat pads and the adipose index, resulting in glucose intolerance and insulin resistance (IR). Transmission electron microscopy showed an increase in alterations of mitochondrial ultrastructure in the gastrocnemius muscle, as well as a decrease in superoxide dismutase (SOD) activity, and an increase in protein carbonylation. Regular physical activity partially reverted these alterations in rats fed a HSD, preventing mitochondrial morphological alterations and IR. Moreover, we observed a decrease in Pgc1α expression (qPCR analysis) in STD-EXE group and a less pronounced reduction in HSD-EXE group after an 8-week period. Thus, regular physical activity (swimming without workload) in rats fed a HSD can prevent mitochondrial dysfunction and IR, highlighting the crucial role for physical activity on metabolic homeostasis.Item Protective effect of Baccharis trimera extract on acute hepatic injury in a model of inflammation induced by acetaminophen.(2014) Pádua, Bruno da Cruz; Rossoni Júnior, Joamyr Victor; Magalhães, Cíntia Lopes de Brito; Chaves, Míriam Martins; Silva, Marcelo Eustáquio; Pedrosa, Maria Lúcia; Souza, Gustavo Henrique Bianco de; Brandão, Geraldo Célio; Rodrigues, Ivanildes Vasconcelos; Lima, Wanderson Geraldo de; Costa, Daniela CaldeiraBackground. Acetaminophen (APAP) is a commonly used analgesic and antipyretic. When administered in high doses, APAP is a clinical problem in the US and Europe, often resulting in severe liver injury and potentially acute liver failure. Studies have demonstrated that antioxidants and anti-inflammatory agents effectively protect against the acute hepatotoxicity induced by APAP overdose. Methods.The present study attempted to investigate the protective effect of B. trimera against APAP-induced hepatic damage in rats. The liver-function markers ALT and AST, biomarkers of oxidative stress, antioxidant parameters, and histopathological changes were examined. Results.The pretreatment with B. trimera attenuated serum activities of ALT and AST that were enhanced by administration of APAP. Furthermore, pretreatment with the extract decreases the activity of the enzyme SOD and increases the activity of catalase and the concentration of total glutathione. Histopathological analysis confirmed the alleviation of liver damage and reduced lesions caused by APAP. Conclusions.The hepatoprotective action of B. trimera extractmay rely on its effect on reducing the oxidative stress caused by APAP-induced hepatic damage in a rat model. General Significance. These results make the extract of B. trimera a potential candidate drug capable of protecting the liver against damage caused by APAP overdose.Item Role of protein kinase A signaling pathway in cyclosporine nephrotoxicity.(2014) França, Flávia Dayrell; Ferreira, Andrea da Fonseca; Lara, R. C.; Rossoni Júnior, Joamyr Victor; Costa, Daniela Caldeira; Moraes, Karen Cristiane Martinez de; Gomes, Dawidson Assis; Tagliati, Carlos Alberto; Schultz, Míriam ChavesCyclosporine is an important immunosuppressive agent; however, nephrotoxicity is one of the main adverse effects. The purpose of this study was to evaluate the effect of inhibiting the protein kinase A (PKA) signaling pathway in nephrotoxicity caused by cyclosporine from the assessment of cell viability, pro-inflammatory cytokines, and nitric oxide (NO) production in LLC-PK1 and MDCK cell lines. Cyclosporine proved to be cytotoxic for both cell lines, as assessed by the mitochondrial enzyme activity assay (MTT), caused DNA fragmentation, determined by flow cytometry using the propidium iodide dye, and activated the PKA pathway (western blot assay). In MDCK cells, the inhibition of the PKA signaling pathway (H89 inhibitor) caused a significant reduction in DNA fragmentation. In both cell lines, the production of IL-6 proved to be a dependent PKA pathway, while TNF-a was not influenced by the inhibition of the PKA pathway. The NO production was increased when cells were pre-incubated with H89 followed by cyclosporine, and this production was dependent on the PKA pathway in LLC-PK1 and MDCK cells lines. Therefore, considering the present study’s results, it can be concluded that the inhibition of PKA signaling pathway can aid in reducing the degree of nephrotoxicity caused by cyclosporine.Item Vildagliptin induces β-Cell neogenesis and Improves the lipid profile in a later phase of type 1 diabetes.(2015) Miranda, Pedro Henrique de Amorim; Monteiro, Otávio Montovanelli; Rossoni Júnior, Joamyr Victor; Silva, Marcelo Eustáquio; Lima, Wanderson Geraldo de; Costa, Daniela CaldeiraRecently, the inhibitor dipeptidyl peptidase-4 has been reported to be beneficial in the treatment of type 1 diabetes mellitus. For the first time, this study evaluates the effect of vildagliptin on β -cell neogenesis and lipid homeostasis in a later phase of type 1 diabetes. In Fischer rats, diabetes was induced with alloxan. After confirmation of diabetic status, the animals received no treatment for 30 days to establish a late phase of the disease these animals. After this period, the animals were treated with vildagliptin via gavage for 30 consecutive days. Fasting blood glucose, serum insulin, lipid profile and pancreatic histology were evaluated. Treatment with vildagliptin increased serum levels of insulin, improved beta cell function and improved the lipid profile. Histological analyses revealed that this treatment increased the populations of pancreatic β-cells in the diabetic animals. The treatment was effective in improving the mass and function of β-cells and contributed to lipid homeostasis, in an experimental model of type 1 diabetes.