The long-term administration of calcineurin inhibitors decreases antioxidant enzyme activity in the rat parotid and submandibular salivary glands

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência do exercício físico sobre o estresse oxidativo, as MAPK e o NF-kB no músculo sóleo de ratos com insuficiência cardíaca induzida por estenose aórtica

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

Changes in the oxidative stress biomarkers in liver of streptozotocin-diabetic rats treated with combretum lanceolatum flowers extract

Aims: The study investigated the in vivo antioxidant activity and the in vitro radical scavenging capacity of the Combretum lanceolatum Pohl (Combretaceae) flowers ethanolic extract (ClEtOH) in streptozotocin-diabetic rats. Place and Duration of Study: Department of Chemistry, Federal University of Mato Grosso, Cuiabá, Brazil; between February 2012 and December 2012. Methodology: Male Wistar rats were divided into four groups: Normal rats treated with water/vehicle (N); diabetic rats treated with water (DC); diabetic rats treated with 250 mg/kg (DT250) or with 500mg/kg (DT500) of ClEtOH. After 21 days of treatment, liver samples were used for the analysis of the oxidative stress biomarkers and activity of antioxidant enzymes. In vitro radical scavenger capacity was investigated by the following methods: DPPH radical scavenging, ABTS radical cation decolorization and crocin bleaching assays. Results: Significant oxidative stress was observed in liver of DC, since the malondialdehyde (MDA, biomarker of lipoperoxidation) levels were increased in comparison with N. Increased activities of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were also observed in DC, which could represent a compensatory mechanism against oxidative stress. Glutathione (GSH) levels were lower and similar between N and DC. The MDA levels were significantly decreased in liver of rats from DT250 and DT500, reaching levels similar those of N, suggesting that ClEtOH prevented lipoperoxidation. The treatment of diabetic rats with ClEtOH also increased the GSH levels, as well as increased the GSH-Px activity, and did not change the SOD activity. The results of in vitro radical scavenging capacity indicated that ClEtOH is highly active. Conclusion: These findings indicate that ClEtOH has antioxidant properties in liver of diabetic rats, decreasing lipoperoxidation and increasing the endogenous antioxidant responses. Both the antihyperglycemic effect and the capacity to scavenge free radicals may be related to the antioxidant activity of ClEtOH in diabetes.

Efeitos da deficiência ou suplementação de zinco sobre a hepatocarcinogênese química em camundongos

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

Influência da suplementação de açaí (Euterpe oleracea Mart.) na ração sobre remodelação cardíaca em ratos expostos à fumaça do cigarro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Mecanismos de ação antioxidante no estado de pós-hipóxia induzida em Phrynops geoffroanus (Testudines:Chelidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da suplementação de açaí (Euterpe oleracea Mart.) na ração sobre a remodelação cardíaca em ratos submetidos a infarto agudo do miocárdio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da temperatura nas respostas aos biocidas diazinon e carbaril em Dilocarcinus pagei Stimpson, 1861

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Selenium and vitamin A and E in the nutrition of very low-birth weight preterm infants

Deficient antioxidant defenses in preterm infants have been implicated in diseases such as bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, periventricular leukomalacia, and intraventricular hemorrhage. The antioxidant properties of selenium, vitamin A, and vitamin E make these elements important in the nutrition of Very Low-Birth Weight (VLBW) infants. Selenium is a component of glutathione peroxidase, an enzyme that prevents the production of free radicals. The decrease in plasma selenium in VLBW infants in the first month after birth makes evident that preterm infants have low selenium store and require supplementation by parenteral and enteral nutrition. A meta-analysis, with only three trials, showed that selenium supplementation did not affect mortality, and the incidence of neonatal chronic lung disease or retinopathy of prematurity, but was associated with a reduction in lateonset sepsis. Most VLBW infants and extremely Low-Birth Weight Infants (ELBW) are born with low vitamin A stores and need vitamin A supplementation by intramuscular or enteral route. Low plasma retinol concentrations increase the risk of chronic lung disease/bronchopulmonary dysplasia and long-term respiratory disabilities in preterm infants. There is evidence that vitamin A supplementation decreases the mortality or oxygen requirement at one month of age, and oxygen requirement at 36 weeks’ postmenstrual age. Vitamin E blocks natural peroxidation of polyunsaturated fatty acids from lipid layers of cell membranes. VLBW infants have a decrease in plasma concentrations in the first month after birth suggesting the need of vitamin E supplementation. A meta-analysis on vitamin E supplementation concluded that vitamin E did not affect mortality, risk of bronchopulmonary dysplasia, and necrotizing enterocolitis but reduced the risk of intraventricular hemorrhage and increased the risk of sepsis. Serum vitamin E concentrations higher than 3.5 mg/dL are associated with a decrease in the risk of severe retinopathy of prematurity, and blindness, but also with an increase in neonatal sepsis. Caution is recommended with the supplementation of high doses of parenteral vitamin E and supplementation that increases serum levels above 3.5 mg/dL. In conclusion: although it is known that preterm infants are deficient in selenium, vitamin A and E, more studies are required to determine the best way to supplement and the impact of supplementation on neonatal outcome.

Metabolismo do malondialdeído em peixes: implicações na avaliação da peroxidação lipídica como biomarcador de contaminação aquática

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da suplementação de alecrim (Rosmarinus oficinallis L.) na ração sobre a remodelação cardíaca em ratos submetidos ao infarto do miocádio

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

Influência da infecção pelo HIV e do uso da terapia antirretroviral nas concentrações de selênio, selenometionina e proteção antioxidante

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

Metabolismo do malondialdeído em peixes: implicações na avaliação da peroxidação lipídica como biomarcador de contaminação aquática

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da suplementação de alecrim (Rosmarinus oficinallis L.) na ração sobre a remodelação cardíaca em ratos submetidos ao infarto do miocádio

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

Influência da infecção pelo HIV e do uso da terapia antirretroviral nas concentrações de selênio, selenometionina e proteção antioxidante

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