Boysenberry and blackcurrant drinks increased the plasma antioxidant capacity in an elderly population but had little effect on other markers of oxidative stress

Abstract

BACKGROUND: The consumption of fruit and vegetables promotes good health by protecting against various degenerative diseases. Even though the constituents responsible are not known, some evidence indicates that the antioxidant properties of fruit and vegetable phytochemicals are responsible. Previous studies have shown that blackcurrant and Boysenberry reduce oxidative stress using in vitro cell systems. The aim of this study was to determine if blackcurrant or Boysenberry drinks could improve measures of oxidative stress and inflammation in an elderly population with below-average memory abilities. The intervention parallel study was fully blinded with a placebo control.

Short-term blackcurrant extract consumption modulates exercise-induced oxidative stress and lipopolysaccharide-stimulated inflammatory responses

“…However, an antioxidant effect was not observed in our sugar placebo group supporting the antioxidant action of the anthocyanins of the BC extract. Similar results have been observed in human feeding trials where the anthocyanins content in plant (13) and fruit (35,36) extracts increased measures of plasma antioxidant capacity, while a sugar placebo had no detectable action. These findings, in combination with the high amount of anthocyanins detected within in the commercial BC extract, leads us to conclude that anthocyanins acted as effective antioxidants in reducing the oxidative stress induced by the 30-min row.…”

“…It is also possible that long-term consumption of these compounds may activate adaptive antioxidant and immune modulatory mechanisms. Indeed, consumption of berryfruit juices over several weeks significantly increased plasma antioxidant capacity in elderly individuals and modulated immune responsiveness (35,38). We detected no change in exercise-induced indices in the placebo groups during our 3-wk crossover study, and hence, while the participant's food diaries revealed some consumption of foods that contain anthocyanins as part of their daily nutrition, effects of this consumption was of no significance.…”

“…Emerging evidence indicates that fruits contain important flavonoids that underlie both antioxidant (6,29,35) and immune modulatory (21,26,53) mechanisms that could alleviate oxidative stress as well as enhance innate and adaptive immunity. However, it is still debatable whether fruit-derived supplements containing these antioxidant and/or anti-inflammatory properties complement or counteract the adaptive health benefits achieved by regular exercise.…”

“…Blackcurrants (BCs) are labeled a "superfruit" with a number of health benefits, especially the alleviation of chronic oxidative stress-related conditions (28). Although these health benefits are attributed a high antioxidant status, recent feeding and cellular studies indicate that BC flavonoids and anthocyanins exhibit a range of health benefits, including antioxidant (35,36) and anti-inflammatory (21,26) properties, although mechanisms underlying these processes are not well understood. We selected an "off the shelf" BC extract that primarily consisted of anthocyanins (and a low amount of vitamin C) to explore the hypothesis that fruit-derived supplements, which exhibit both antioxidant and anti-inflammatory properties, complement the putative health benefits of regular exercise.…”

Impact of Fruit Beverage Consumption on the Antioxidant Status in Healthy Women

“…Another study was carried out in subjects with preestablished endogenous oxidative stress derived from smoking [33] . Moreover, in several studies [22,23,[33][34][35] , the effects of dietary antioxidants were enhanced in subjects under conditions of oxidative stress compared with healthy people with a well-balanced redox status, in whom the detection of antioxidant status variations is more problematic. Accordingly, 750 ml of cranberry juice/day consumed by 20 healthy female volunteers for 2 weeks did not modify plasma antioxidant capacity or the activity of SOD, catalase and glutathione peroxidase in erythrocytes -and these observations have been attributed to the use of nutritional doses instead of pharmacological doses, and also to the lack of endogenous oxidative stress in healthy volunteers [24] .…”