Oxidação da hemoglobina como modelo de estudo do sistema de óxido-redução eritrocitário: interação entre nitrito de sódio, azul de metileno e cistamina

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Treinamento físico e antioxidantes enzimáticos no tecido cerebral de ratos diabéticos experimentais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ecological relevance of sentinels' biomarker responses: A multi-level approach

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Gastroprotective effects (in rodents) of a flavonoid rich fraction obtained from Syngonanthus macrolepsis

Objectives: Syngonanthus macrolepis, popularly known in Brazil as sempre-vivas', is a plant from the family Eriocaulaceae, it is found in the states of Minas Gerais and Bahia. The species contains a variety of constituents, including flavonoids with gastroprotective effect. In this work, a flavonoid-rich fraction (Sm-FRF) obtained from scapes of S.macrolepis was investigated for preventing gastric ulceration in mice and rats.MethodsThe activity was evaluated in models of induced gastric ulcer (absolute ethanol, stress, non-steroidal anti-inflammatory drugs and pylorus ligation). The cytoprotective mechanisms of the Sm-FRF in relation to sulfhydryl (SH) groups, nitric oxide (NO) and antioxidant enzymes were also evaluated.Key findingsThe Sm-FRF (100mg/kg, p.o.) significantly reduced gastric injury in all models, and did not alter gastric juice parameters after pylorus ligation.ConclusionsThe results indicate significant gastroprotective activity for the Sm-FRF, which probably involves the participation of both SH groups and the antioxidant system. Both are integral parts of the gastrointestinal mucosa's cytoprotective mechanisms against aggressive factors.

Mecanismos da infertilidade causada por Gossipol em ratos e efeito protetor da vitamina E

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Energy restriction and impact on indirect calorimetry and oxidative stress in cardiac tissue in rat

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação gastroprotetora da epicatequina e verificação de seus mecanismos de ação

The stomach is an exceptional organ, which functions are sterilize food ingested, form the primitive bolus, digest lipids and proteins, and to store food temporarily in the gastrointestinal tract. Its capacity of digesting food without digesting itself is amazing. This fact occurs due to innumerous protective substances adjacent to the gastric mucosa. When aggressive factors overwhelm the protective factors, a lesion in the gastric mucosa is formed. Lesions that reach the lamina propria are called gastric ulcers, which are classified macroscopically as openings on the gastric wall and; microscopically, as a gastric injury characterized with epithelial desquamation, mucosal hemorrhage, glandular damage and eosinophilic infiltration. The current therapy available is effective, although it causes collateral effects, therefore researching new drugs is necessary. This work aim to evaluate the gastroprotective effect of epicatechin against gastric lesions induced by absolute ethanol and non steroidal anti-inflammatory drugs which are the main causes of this disease currently, yet we aim to study the main mechanisms of action responsible for the gastroprotective effect. The results show that epicatechin has a significant macroscopic and microscopic gastroprotective effect against gastric injuries induced by ethanol and indomethacin, acting locally by augmenting gastric mucus secretion and it also acts via antioxidant system by holding total glutathione levels. Epicatechin’s gastroprotective mechanisms depend on the activation of sulfhydryl compounds and doesn’t depend on the NO-synthase enzyme

Effect of melatonin intake on oxidative stress biomarkers in male reproductive organs of rats under experimental diabetes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Biochemical responses in mussels Perna perna exposed to diesel B5

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mechanisms involved in reproductive damage caused by gossypol in rats and protective effects of vitamin E

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ulcer healing and mechanism(s) of action involved in the gastroprotective activity of fractions obtained from Syngonanthus arthrotrichus and Syngonanthus bisulcatus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ação de fungicidas no desenvolvimento de plantas de tomate, em condições de ambiente protegido

Pós-graduação em Agronomia (Horticultura) - FCA

Marcadores de ativação imune, inflamação crônica e estresse oxidativo em pessoas que vivem com o HIV/Aids: a busca do melhor prognóstico

Pós-graduação em Doenças Tropicais - FMB

Parenteral administration of vitamins A, D and E on the oxidative metabolism and function of polymorphonuclear leukocytes in swine

The weaning period of piglets is characterized by physiological alterations, such as decreased weight gain, increased reactive oxygen species (ROS) and increased serum cortisol levels with possible effects on the immune response. The effect of parenteral administration of vitamins A, D and E on production performance, oxidative metabolism, and the function of polymorphonuclear leukocytes (PMNLs) was assessed in piglets during the weaning period. The sample was comprised of 20 male piglets that were given an injectable ADE vitamin combination (135,000 IU vitamin A, 40,000 IU vitamin D and 40mg vitamin E/animal) at 20 and 40 days of age. Weight gain, concentration of reduced glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD) and the microbicidal and phagocytic activity of PMNLs were assessed. No difference was observed in the average piglet weight during the study; however, a greater percentage of weight gain was observed after weaning in the treated group. The concentrations of GSH and SOD did not differ between groups, although lipid peroxidation was greater in the control group at 60 days of age. The investigated variables of oxidative metabolism were correlated as follows: -0.41 for GSH and MDA, -0.54 for GSH and SOD and 0.34 for MDA and SOD. The intensity of intracellular ROS production, the percentage of ROS-producing PMNLs and the intensity of phagocytosis by PMNLs did not differ between treatment groups. Administration of the injectable ADE combination improved the percentage of weight gain between 20 and 40 days of age, decreased oxidative stress at 60 days of age and did not influence the function of PMNLs in piglets.

Biomarker responses as indication of contaminant effects in Oreochromis niloticus

The current study investigated oxidative stress parameters (enzymes activities, metallothionein content and lipid peroxidation) in freshwater fish, Oreochromis niloticus, tilapia exposure to Monjolinho River (in 4 months of year: January, April, July and November). One critical site in Monjolinho River (site B) was assessed in comparison to a reference site (site A). Water pH and oxygen concentration was lower than that recommended by CONAMA (Brazilian National Environmental Committee), resolution 357/2005 for protection of aquatic communities, and ammonium and the metals Cu, Zn, Mn and Fe (on all months) concentrations were higher than the maximum concentration recommended. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were significantly decreased in liver and muscle in tila. pia from Monjolinho River, throughout the year, in relation to reference except in gills that SOD activity increased. Glutathione S-transferase (GST) activity was significantly increased in liver of the tilapia from Monjolinho River in all sites, in relation to reference except in gills that GST activity increased in July and decreased in November, suggesting that GST activity could be induced to neutralize the pollutants toxicity. On the other hand, GST activity was significantly decreased in white muscle indicating a toxic effect of pollutants, resulting in a decreased ability of tilapia to perform defense reactions associated to GSTs. The decrease of catalase (CAT) activity in gills of the O. niloticus together with the increase of SOD activity, could explain the increased lipid peroxidation (LPO) level in this organ. Metallothionein levels in liver and gills were significantly high in all sites. Results indicate that the exposure to metals caused severe damage to tissues; despite the consensually assumed antioxidant induction as a sign of exposure to contaminants the effects seem in part to be mediated by suppression of antioxidant system with SOD, CAT and GPx as potential candidates for tissues toxicity biomarkers of pollutants. (c) 2012 Elsevier Ltd. All rights reserved.