Evaluation of Renal Protection From High Doses of Melatonin in an Experimental Model of Renal Ischemia and Reperfusion in Hyperglycemic Rats

Background. Melatonin is a free radical scavenger with important actions in the study of renal ischemia and reperfusion (I/R). This study evaluated possible renal protection of high doses of melatonin in an experimental model of I/R in which rats were submitted to acute hyperglycemia under anesthesia with isoflurane.Method. Forty-four male Wistar rats, weighing more than 300 g, were randomly divided into 5 groups: G1, sham (n = 10); G2, melatonin (n = 10; 50 mg.kg(-1)); G3, hyperglycemia (n = 9; glucose 2.5 g.kg(-1)); G4, hyperglycemia/melatonin (n = 10; 2.5 g.kg(-1) glucose + melatonin 50 mg.kg(-1)); and G5, I/R (n = 5). In all groups, anesthesia was induced with 4% isoflurane and maintained with 1.5% to 2.0% isoflurane. Intraperitoneal injection of melatonin (G1, G4), glucose (G3, G4), or saline (G1, G5) was performed 40 minutes before left renal ischemia. Serum plasma values for creatinine and glucose were determined at baseline (M1), immediately following reperfusion (M2), and 24 hours after completion of the experiment (M3). Histological analysis was performed to evaluate tubular necrosis (0-5).Results. Serum glucose was higher at M2 in the groups supplemented with glucose, hyperglycemia (356.00 +/- 107.83), and hyperglycemia/melatonin (445.3 +/- 148.32). Creatinine values were higher at T3 (P = .0001) for I/R (3.6 +/- 0.37), hyperglycemia/melatonin (3.9 +/- 0.46), and hyperglycemia (3.71 +/- 0.69) and lower in the sham (0.79 +/- 0.16) and melatonin (2.01 +/- 1.01) groups, P < .05. Histology showed no necrosis injury in the G1, lesion grade 2 in the G2, and severe acute tubular necrosis in the G3: (grade 4), G4: (grade 5) and G5: (grade 4) groups (P < .0001).Discussion. Melatonin protected the kidneys submitted to I/R in rats without hyperglycemia; however, this did not occur when the I/R lesion was associated with hyperglycemia.Conclusions. Due to its antioxidant and antiapoptotic action, melatonin was able to mitigate, but not prevent acute tubular necrosis in rats with hyperglycemia under anesthesia by isoflurane.

Antioxidant activity and determination of total phenol contents, carotenoids, beta-carotene, lycopene and zinc in white, yellow and pinkish varieties of manihot esculenta crantz

There are cassava varieties that present compounds as carotenoids, beta-carotene, lycopene and minerals important for human and animal health. The present study evaluated the antioxidant activity of the white, yellow and pinkish varieties of Manihot esculenta, by mean of the DPPH test and by the ferrous ion-chelating activity. Furthermore, the total phenols, carotenoids, beta-carotene, lycopene and zinc contents were also determined. Utilizing the DPPH test it was possible to find that extracts of boiled samples presented higher antioxidant activity (89.53% -pinkish) in comparison to the fresh samples (1.97% -white). For the ferrous ion-chelating test, the highest activity was found for the boiled pinkish variety extract (63.43%) and the lowest was for fresh yellow extract (17.34%) the white sample did not present activity. The highest concentration of total phenols and zinc content was obtained for the boiled pinkish variety extract 136.12 mg EAG/g of extract and 0,811ppm, respectively, in the concentration of 1000 mu g/mL. The pinkish variety presented also higher quantity of pigments, including carotenoid (29.40 mu g/g), beta-carotene (9.14 mu g/100g) and lycopene (68.92%). According to the results obtained in this study it was possible to conclude that the yellow and pinkish varieties of M. esculenta present quantity of phenolic compounds and minerals sufficient to attribute the antioxidant activity and may thus contribute to reduce oxidative damage and be used as nutraceuticals or directly ingested in the diet to maintain good health.

Ethyl Ferulate, a Component with Anti-Inflammatory Properties for Emulsion-Based Creams

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aditivos fitogênicos na dieta de frangos de corte: desempenho, qualidade de carne e estabilidade oxidativa da carne e sangue

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

Avaliação do potencial antioxidante, citotóxico e fotoprotetor de extratos de Hymenaea courbaril L. e Hymenaea stigonocarpa Mart. ex Hayne

Pós-graduação em Biociências - FCLAS

Capacidade antioxidante e estabilidade oxidativa de Gengiber officinale

The main objectives of this work were to evaluate the antioxidant activity and to determine of an ethanolic ginger extract total phenolic compounds concentration, as well as verifying its behavior by means of the oxidative stability, when added to refined soybean oil in concentrations of 0, 500, 1000, 1500, 2000 and 2500 mg/kg. The maximum antioxidant activity and EC50, concentration of the extract to achieve 50% of the antioxidant activity, value determined by free radical DPPH method were 79.1% and 42.6 g/mL, respectively. The total phenolic compounds concentration, determined to Folin-Ciocalteu method, was 251 mg/g. The induction period of the samples increased according to the augment of the extract concentration in the oil when evaluated using oxidative stability through the Rancimat equipament. It was possible to conclude that the ginger extracts possess effective action against the lipid oxidation and can be applied in foods as natural antioxidant.

Atividade antioxidante e determinação de fenóis totais, carotenoides, betacarotenos, licopeno e zinco em variedades branca, amarela e rosada de Manihot Esculenta Crantz

There are cassava varieties that present compounds as carotenoids, beta-carotene, lycopene and minerals important for human and animal health. The present study evaluated the antioxidant activity of the white, yellow and pinkish varieties of Manihot esculenta, by mean of the DPPH test and by the ferrous ion-chelating activity. Furthermore, the total phenols, carotenoids, beta-carotene, lycopene and zinc contents were also determined. Utilizing the DPPH test it was possible to find that extracts of boiled samples presented higher antioxidant activity (89.53% - pinkish) in comparison to the fresh samples (1.97% - white). For the ferrous ion-chelating test, the highest activity was found for the boiled pinkish variety extract (63.43%) and the lowest was for fresh yellow extract (17.34%) the white sample did not present activity. The highest concentration of total phenols and zinc content was obtained for the boiled pinkish variety extract 136.12 mg EAG/g of extract and 0,811ppm, respectively, in the concentration of 1000 µg/mL. The pinkish variety presented also higher quantity of pigments, including carotenoid (29.40 µg/g), beta-carotene (9.14 µg/100g) and lycopene (68.92%). According to the results obtained in this study it was possible to conclude that the yellow and pinkish varieties of M. esculenta present quantity of phenolic compounds and minerals sufficient to attribute the antioxidant activity and may thus contribute to reduce oxidative damage and be used as nutraceuticals or directly ingested in the diet to maintain good health.

Novel solid state nitric oxide sensor using siloxane-poly (oxypropylene) (PPO)

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

Metabolismo oxidativo sérico em ratos diabéticos com lesão periapical

Pós-graduação em Ciência Odontólogica - FOA

El papel del óxido nítrico en la modulación del proceso inflamatorio de la enfermedad periodontal

Nitric oxide (NO) is a free radical with participation in almost all physiologic host processes; however, in high concentrations it may damage the tissues. Its immunoregulatory action is present in the inflammation and in auto-immune mechanisms, being intensively studied in the medical area. Recently, some studies have also reported that NO could play a role as etiopathogenic factor of the periodontal disease, which shows inflammatory and multifactorial course. Due to beneficial or damage effects of NO, according to its concentrations, some studies have been focused in the evaluation of inhibitor of NO-Synthase (NOS) as therapeutic agents in inflammatory processes. In this context, the aim of this study was to report the role of NO and NOS inhibition in the periodontal disease modulation process. In conclusion, it could be suggested that NO seems to play an essential role in evolution of inflammatory periodontal disease, and that the NOS inhibition may be considered as a promising therapeutic in modulation of inflammatory process.

Caracterização Físico-Química de Polpas de Frutas do Bioma Amazônia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Zirconium-methacrylate oxoclusters as new hybrid materials for the modification of epoxy systems

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Participação do óxido nítrico na fisiopatologia da doença renal crônica

Nitric oxide (NO) is a free radical gas, inorganic, which has seven electrons of nitrogen and oxygen eight, possessing an unpaired electron. This radical is produced from L-arginine by a reaction mediated by the enzyme NO synthase. NO it is about a radical of who acts abundant on a variety of biological processes, particularly when produced by endothelial cells plays a significant role in cardiovascular control, as a modulator of peripheral vascular resistance and platelet aggregation. This free radical has also a neurotransmitter and mediator of the immune system. NO kidney function has been considered in many physiological functions such as: (a) regulation of hemodynamics and glomerular function tubuloglomerular, (b) participation in pressure natriuresis (c) maintaining medullar perfusion (d) inhibiting sodium reabsorption tubular, and (e) acting as a modulator of the activity of the sympathetic nervous system. Given these functions, the occurrence of its deficiency is associated with chronic kidney disease (CKD) in vasoconstriction and consequently glomerular hypertension, high blood pressure (HBP), proteinuria and progression of renal dysfunction. This work has the scope to describe the role of NO in renal physiology and pathophysiology of CKD.

Chemical, enzymatic and cellular antioxidant activity studies of Agaricus blazei Murrill

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

Evaluation of DNA damage and lipoperoxidation of propofol in patients undergoing elective surgery

Inhaled anaesthetics have been studied regarding their genotoxic and mutagenic potential in vivo. Propofol differs from volatile anaesthetics because it does not show mutagenic effects and it has been reported to be an antioxidant. However, there are no studies with propofol and genotoxicity in vivo. The study aimed to evaluate the hypothesis that propofol is not genotoxic and it inhibits lipid peroxidation [malondialdehyde (MDA)] in patients undergoing propofol anaesthesia. ASA physical status I patients scheduled for elective surgery, lasting at least 90 min, were enrolled in this study. Initially, the estimated plasma concentration of propofol was targeted at 4 microg ml(-1) and then maintained at 2-4 microg ml(-1) until the end of surgery. Haemodynamic data were determined at baseline (before premedication) and in conjunction with target-controlled infusion of propofol: after tracheal intubation, 30, 60 and 90 min after anaesthesia induction and at the end of the surgery. Venous blood samples were collected at baseline, after tracheal intubation, at the end of the surgery and on the postoperative first day for evaluating DNA damage in white blood cells (WBCs), by comet assay, and MDA levels. Haemodynamic data did not differ among times. No statistically significant differences were observed for the levels of DNA damage in WBCs, nor in plasma MDA, among the four times. Propofol does not induce DNA damage in WBCs and does not alter MDA in plasma of patients.