Magnesium Status and Its Association with Oxidative Stress in Obese Women.

The aim of this study was to assess the relationship between magnesium status and oxidative stress in obese and nonobese women. This cross-sectional study included 83 women, aged between 20 and 50 years, who were divided into two groups: the obese group (n = 31) and the control group (n = 52). The control group was age-matched with the obese group. Magnesium intake was monitored using 3-day food records and NutWin software version 1.5. The plasma and erythrocyte magnesium concentrations were determined by flame atomic absorption spectrophotometry. Plasma levels of thiobarbituric acid reactive substances (TBARS) were determined as biomarkers for lipid peroxidation and therefore of oxidative stress. The mean values of the magnesium content in the diet were found to be lower than those recommended, though there was no significant difference between groups (p > 0.05). The mean concentrations of plasma and erythrocyte magnesium were within the normal range, with no significant difference between groups (p > 0.05). The mean concentration of plasma TBARS was higher in obese woman, and the difference between the groups was statistically different (p < 0.05). There was a positive correlation between erythrocyte magnesium and plasma TBARS in the obese group (p = 0.021). Obese patients ingest low dietary magnesium content, which does not seem to affect the plasma and erythrocyte concentrations of the mineral. The study showed a negative correlation between erythrocyte magnesium concentrations and plasma TBARS, suggesting the influence of magnesium status on the parameters of oxidative stress in obese women.

Hepatic function and antioxidant activity in diabetic rats subjected to diet supplemented with multimixture.

INTRODUCTION: Food and dietetic components have received considerable attention as auxiliary feeding resources on controlling of chronic non-transmissible diseases, among them diabetes. This study evaluated the effect of supplementary diet with multimixture based on linseed, sesame, oats and sunflower seeds on the hepatic function and antioxidant activity of diabetic rats. METHODS: Male rats were distributed on groups of seven animals: diabetic control (DC), diabetics subject to multimixture diet (DM), diabetic with insulin (DI), and normal control (NC). The treatment was started on the 5th day after diabetes induction with 40 mg/kg i.v. streptozotocin on tampon citrate and kept during 50 days. RESULTS: The ethereal extract of the supplemented diet showed a higher content of phenolics (p < 0.05) compared to other extracts of the supplemented diet and the ethereal extract of the standard diet. There was no difference in antioxidant in vitro activity of the utilized diets. Concerning to transaminases, significant bigger ALT levels (p < 0.05) were present on diabetic groups compared to NC. The relative liver weight on diabetic groups was significantly higher (p < 0.001) compared to NC group. Non-proteic sulfhydryl group levels were significantly higher (p < 0.05) on DM and I groups when compared to DM and NC. Only the treatment with insulin resulted in an improvement of antioxidant activity concerning to hepatic catalase. The supplementation with multimixture did not improve the metabolic control of diabetes. CONCLUSION: The multimixture treatment showed an isolated improvement on antioxidant activity in the hepatic tissue, evidenced by the increasing on non-proteic sulfhydryl group levels.

IN VITRO AND IN VIVO ANTIOXIDANT ACTIVITY OF BURITI FRUIT (MAURITIA FLEXUOSA L.F.).

INTRODUCTION: studies have shown high concentration of monounsaturated fatty acids, carotenoids, polyphenols and ascorbic acid in Buriti fruit (Mauritia flexuosa L.f.). This study evaluated the in vitro and in vivo antioxidant activities of buriti fruit (Mauritia flexuosa L.f.). METHODS: the chemical composition and total phenolic and carotenoid contents of the buriti pulp and the feed rations were determined, and the in vitro antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay. Wistar rats (21 days old) were randomly allocated (n=10) into a control groups and experimental groups (feed enriched with buriti pulp). After 60 days, the in vivo antioxidant activity was evaluated through the determination of the catalase activity and non-protein sulfhydryl (NPSH) groups in the liver and quantification of malondialdehyde (MDA) in the plasma and tissues. RESULTS: high contents of oleic fatty acids (73.3%), phenolic compounds (192 ± 0.3 mg/100 g) and carotenoids (23.9 ± 0.5 mg/100 g) as well as elevated in vitro antioxidant activity were found in the buriti pulp. The enriched diet had higher contents of phenols and carotenoids as well as higher antioxidant activity compared with the standard feed (p < 0.05). There were no differences between the groups regarding catalase activity in the liver and MDA concentrations in the plasma, liver and kidneys. The male rats of the experimental group had higher liver concentrations of NPSH compounds (p < 0.05). CONCLUSION: these results may corroborate the claim that buriti fruit is an antioxidant functional food and support its utilization in a nutritionally balanced diet.

Introducción: estudios previos han demostrado que la fruta Burití (Mauritia flexuosa L.f). posee una alta concentración de ácidos grasos monoinsaturados, carotenoides, polifenoles y ácido ascórbico. Este estudio evaluó la actividad antioxidante in vitro e in vivo del Burití. Métodos: fueron determinadas la composición química, el contenido de compuestos fenólicos y de carotenoides tanto de la pulpa del Burití como de las raciones de alimento. La actividad antioxidante in vitro fue analizada utilizando el ensayo del radical 2,2-difenil-1-picrilhidrazil (DPPH). Ratas Wistar (21 días de edad) fueron asignadas al azar (n = 10) en grupos controles y grupos experimentales (alimentación enriquecida con pulpa de Burití). Después de 60 días, la actividad antioxidante in vivo se evaluó mediante la actividad enzimática de la catalasa y grupos sulfhidrílo no proteico (NPSH) en el hígado, y se cuantificó el malondialdehído (MDA) en plasma y tejidos. Resultados: la pulpa del Burití presentó alto contenido de ácido graso oleico (73,3%), compuestos fenólicos (192 ± 0,3 mg/100 g) y carotenoides (23,9 ± 0,5 mg/100 g), así como una elevada actividad antioxidante in vitro. La dieta enriquecida tenía mayor contenido de fenoles y carotenoides, y una mayor actividad antioxidante en comparación con la alimentación estándar (p < 0,05). No se observaron diferencias entre los grupos con respecto a la actividad de la catalasa en el hígado y las concentraciones de MDA en plasma, hígado y riñones. Las ratas macho del grupo experimental tuvieron concentraciones hepáticas más altas de NPSH (p < 0,05). Conclusión: estos resultados pueden corroborar la hipótesis de que la fruta Burití es un alimento funcional antioxidante y su consumo es conveniente en una dieta nutricionalmente equilibrada.