Effect of an antioxidant functional food beverage on exercise-induced oxidative stress: a long-term and large-scale clinical intervention study.

The efficacy of long-term intake of a novel functional food supplement Funciona™ containing vitamins and juiced fruits was evaluated in order to assess the net effect of physical activity and antioxidant potentials in healthy older adult population. The long-term (2 years) and large-scale (400 older adult subjects) interventional study was based on both moderate-intensity exercise practice and concurrent supplementation. Sustained exercise-induced oxidative stress as reflected in significantly increased blood thiobarbituric acid-reactive substances (TBARS) (+15%), protein carbonyl groups (PC) (+18%) and oxidized glutathione (GSSG) (+112%) concentrations, and leukocyte 8-OHdG contents (23%). Exercise decreased the reduced/oxidized glutathione (GSH/GSSG) molar ratio (-43%) and plasma vitamin C levels (-22%). Supplementation with Funciona™ was significant in preventing oxidative damage to lipid, protein and DNA, and normalizing blood GSSG, GSH/GSSG and vitamin C levels. Thus daily intake of the antioxidant functional beverage counteracts the exercise-induced oxidative stress in free-living older subjects, and might be necessary to restore impaired antioxidant balance due long-term regular exercise.

Antioxidantes, atividade física e estresse oxidativo em mulheres idosas / Antioxidants, physical activity and oxidative stress in older women

OBJETIVO: Verificar a influência da suplementação de vitaminas antioxidantes na dieta de mulheres idosas que praticam exercícios físicos regulares, sobre o estresse oxidativo, indicadores da saúde física e risco de enfermidades cardiovasculares (ECV). MÉTODO: Foram observados dois grupos (S e C) de mulheres com idades entre 60 e 80 anos participantes de um programa de atividades físicas durante 58 semanas, com freqüência de três vezes por semana e duração de 50 a 55 minutos cada sessão. A dieta habitual do Grupo S (n=36) foi suplementada diariamente com 330 ml de uma bebida antioxidante (FuncionaTM); o Grupo C (n=32) ingeriu água e se caracterizou como controle. Como indicadores do estresse oxidativo foram determinadas as concentrações plasmáticas de glutationa reduzida (GSH) e oxidada (GSSG), calculada a relação molar GSH/GSSG, e identificado o dano oxidativo em lipídios e proteínas. As condições físicas e cardiovasculares foram avaliadas por meio dos parâmetros antropométricos habituais (peso, altura e índice de massa corporal) e da pressão arterial. RESULTADOS: O Grupo C apresentou aumentos significativos do estresse oxidativo, redução da pressão arterial e dos valores médios de indicadores de risco de ECV. O Grupo S teve o estresse oxidativo reduzido significativamente e apresentou incremento dos ganhos cardiovasculares. Não foram identificadas significâncias em relação aos efeitos ergogênicos. CONCLUSÃO: Os dados indicam que mulheres idosas que realizam exercícios físicos freqüentes melhoram suas condições físicas e cardiovasculares e que o suplemento dietético continuado de alimentos funcionais antioxidantes podem minimizar os efeitos danosos das espécies reativas de oxigênio.

OBJECTIVE: To verify the influence of dietary antioxidant supplementation in older women who regularly practice physical activities, on the occurrence of oxidative stress, physical health and risk of cardiovascular diseases (CVD). METHOD: Two groups (S and C) of women, with age ranging from 60 to 80 years old, were observed. Both groups took part in a physical activity program for 58 weeks, three times a week, for about 50 to 55 minutes each session. The diet of group S (n=36) was daily supplemented with 330 ml of a functional antioxidant beverage, FuncionaTM; Group C (n=32) ingested water and was used as Control. As oxidative stress indicators, the plasmatic concentrations of reduced (GSH) and oxidized (GSSG) glutathione were determined; the molar GSH/GSSG ratio was calculated, and the oxidative damage in lipids and proteins was evaluated. The physical and cardiovascular conditions were evaluated through routine anthropometric parameters (weight, stature and BMI) and blood pressure. RESULTS: Group C presented significant increases of oxidative stress, reduction in the blood pressure and in the indicators of cardiovascular risks. Group S presented significant reduction of the oxidative stress and increment of the cardiovascular gains. Significance concerning the ergogenic effects has not been identified. CONCLUSION: Our data suggest that regular exercise in older women can improve physical and cardiovascular conditions. Moreover, daily intake of functional antioxidant supplement can minimize harmful effects of the reactive oxygen species.

Exercise, oxidative stress and risk of cardiovascular disease in the elderly. Protective role of antioxidant functional foods.

Free radicals and oxidative stress are involved in the pathogenic mechanisms of cardiovascular disease (CVD), diabetes and cancer. Exercise is a useful strategy for preventing CVD but in elderly persons it can enhance oxidative stress, which is why some studies recommend antioxidant supplementation for exercising elderly subjects. This intervention study was performed on 320 elderly subjects following a Geriatric Revitalization Program (GEREPRO) to maintain physical health and reduce CVD risk. GEREPRO was based on regular exercise concurrent with a nutritional antioxidant treatment based on daily intake of a functional antioxidant food, Biofrutas. Sustained exercise (10 months, 3 sessions/week) significantly increased cardiorespiratory fitness and plasma HDL-cholesterol; it reduced some predictors of cardiovascular risk (arterial pressure, LDL-cholesterol, total cholesterol/LDL-C, LDL-C/HDL-C), but significantly enhanced some biomarkers of oxidative stress. Concurrent antioxidant supplementation did not produce any ergogenic effects but, meaningfully, enhanced some positive effects of exercise on physical health and the CDV risk index, and it totally prevented the exercise-induced oxidative stress. Our results show that regular and moderate exercise improves cardiorespiratory function and reduces CVD risk in elderly people, while concurrent antioxidant supplementation modulates oxidative insult during exercise in the elderly and enhances the beneficial effects of exercise.

S-adenosylmethionine protects against intrabiliary glutathione degradation induced by long-term administration of cyclosporin A in the rat.

We investigate the ability of S-adenosylmethionine (SAMe) to antagonize the cyclosporine A (CyA)-induced inhibition of biliary glutathione efflux induced by long-term administration of CyA (10 mg/kg per day-CyA10 or 20 mg/kg per day-CyA20 for 4 weeks) in rats. CyA treatment reduced the liver content of total glutathione and caused a significant increase in the oxidized-to-reduced glutathione ratio and the thiobarbituric acid-reactive substances (TBARS) concentration. When the rats were concurrently treated with SAMe (10 mg/kg twice daily) and CyA, all these parameters did not significantly differ from control values. Treatment with CyA induced a significant increase in liver GGT activity that was attenuated by coadministration of SAMe. Biliary efflux of total glutathione was significantly reduced in animals treated with CyA. These changes were abolished by SAMe administration. Following inhibition of the intrabiliary catabolism of the tripeptide by acivicin, glutathione efflux rates increased to a lesser extent in animals cotreated with SAMe when compared to those receiving only CyA. The significant decrease in biliary efflux of oxidized glutathione induced by CyA was totally (S + CyA10) or partially (S + CyA20) prevented by coadministration of SAMe. Our observations confirm that SAMe cotreatment in rats antagonizes CyA-induced inhibition in the biliary efflux of glutathione and suggest that protection against intrabiliary glutathione degradation plays a major role in this protective effect.

Effects of S-adenosylmethionine on intrabiliary glutathione degradation induced by long-term administration of cyclosporin A in the rat.

We investigate the ability of S-adenosylmethionine (SAMe) to antagonize the cyclosporine A (CyA)-induced inhibition of biliary glutathione efflux induced by long-term administration of CyA (10 mg/kg per day-CyA(10) or 20 mg/kg per day-CyA(20) for 4 weeks) in rats. CyA treatment reduced the liver content of total glutathione and caused a significant increase in the oxidized-to-reduced glutathione ratio and the thiobarbituric acid-reactive substances (TBARS) concentration. When the rats were concurrently treated with SAMe (10 mg/kg twice daily) and CyA, all these parameters did not significantly differ from control values. Treatment with CyA induced a significant increase in liver GGT activity that was attenuated by coadministration of SAMe. Biliary efflux of total glutathione was significantly reduced in animals treated with CyA. These changes were abolished by SAMe administration. Following inhibition of the intrabiliary catabolism of the tripeptide by acivicin, glutathione efflux rates increased to a lesser extent in animals cotreated with SAMe when compared to those receiving only CyA. The significant decrease in biliary efflux of oxidized glutathione induced by CyA was totally (S + CyA(10)) or partially (S + CyA(20)) prevented by coadministration of SAMe. Our observations confirm that SAMe cotreatment in rats antagonizes CyA-induced inhibition in the biliary efflux of glutathione and suggest that protection against intrabiliary glutathione degradation plays a major role in this protective effect.