Antioxidant Research Laboratory
Antioxidant Research Laboratory
Karlsen A.,University of Oslo |
Svendsen M.,University of Oslo |
Seljeflot I.,University of Oslo |
Sommernes M.-A.,University of Oslo |
And 19 more authors.
British Journal of Nutrition | Year: 2011
It has been suggested that antioxidants attenuate oxidative stress and prevent oxidative stress-related diseases. Paradoxically, randomised controlled trials (RCT) using pharmacological doses of antioxidant supplements have demonstrated harmful effects in smokers. The aim of the present study was to test the compliance, tolerability and safety of two food-based antioxidant-rich diets in smokers. One of the diets provided antioxidants at levels similar to that used in RCT using supplements which previously have generated harmful effects. The present study followed a randomised, parallel-arm dietary intervention for 8 weeks (n 102) in male smokers (age â‰¥ Â 45 years). Participants were randomised to either antioxidant-rich diet, kiwi fruit or control groups. The antioxidant-rich foods provided about 300Â mmol antioxidants/week from a wide range of plant-based food items. The kiwi fruit group consumed three kiwi fruits/d. Compliance to both diets was good. Only mild, undesirable events were reported by a minority of the participants. The safety of both diets was demonstrated as no potentially harmful or pro-oxidative effects were observed. In the antioxidant-rich diet group, the mean intake of antioxidants increased from 30Â mmol/d at baseline to 62Â mmol/d during the intervention. In conclusion, we have demonstrated that male smokers can comply with two food-based antioxidant-rich diets. Furthermore, the present study is the first to demonstrate the tolerability and safety of dietary antioxidants at levels similar to dosages provided in RCT using supplements. Such diets may be useful in future studies investigating whether dietary antioxidants may reduce oxidative stress and related diseases. © 2011 The Authors.
Karlsen A.,University of Oslo |
Paur I.,University of Oslo |
Bohn S.K.,University of Oslo |
Sakhi A.K.,University of Oslo |
And 6 more authors.
European Journal of Nutrition | Year: 2010
Purpose: Bilberries are abundant in polyphenols. Dietary polyphenols have been associated with strategies for prevention and treatment of chronic inflammatory diseases. We investigated the effect of bilberry juice on serum and plasma biomarkers of inflammation and antioxidant status in subjects with elevated levels of at least one risk factor for cardiovascular disease (CVD). Methods: In a randomized controlled trial, participants consumed either bilberry juice (n = 31) or water (n = 31) for 4 weeks. Results: Supplementation with bilberry juice resulted in significant decreases in plasma concentrations of C-reactive protein (CRP), interleukin (IL)-6, IL-15, and monokine induced by INF-γ (MIG). Unexpectedly, an increase in the plasma concentration of tumor nuclear factor-α (TNF-α) was observed in the bilberry group. CRP, IL-6, IL15, MIG, and TNF-α are all target genes of nuclear factor- kappa B (NF-κB), -a transcription factor that is crucial in orchestrating inflammatory responses. Plasma quercetin and p-coumaric acid increased in the bilberry group, otherwise no differences were observed for clinical parameters, oxidative stress or antioxidant status. Furthermore, we studied the effect of polyphenols from bilberries on lipopolysaccharide (LPS)-induced NF-κB activation in a monocytic cell line. We observed that quercetin, epicatechin, and resveratrol inhibited NF-κB activation. Conclusions: These findings suggest that supplementation with bilberry polyphenols may modulate the inflammation processes. Further testing of bilberry supplementation as a potential strategy in prevention and treatment of chronic inflammatory diseases is warranted. © 2010 Springer-Verlag.
Flammer A.J.,University of Zürich |
Flammer A.J.,Rochester College |
Sudano I.,University of Zürich |
Wolfrum M.,University of Zürich |
And 12 more authors.
European Heart Journal | Year: 2012
Aims Flavanol-rich chocolate (FRC) is beneficial for vascular and platelet function by increasing nitric oxide bioavailability and decreasing oxidative stress. Congestive heart failure (CHF) is characterized by impaired endothelial and increased platelet reactivity. As statins are ineffective in CHF, alternative therapies are a clinical need. We therefore investigated whether FRC might improve cardiovascular function in patients with CHF.Methods and resultsTwenty patients with CHF were enrolled in a double-blind, randomized placebo-controlled trial, comparing the effect of commercially available FRC with cocoa-liquor-free control chocolate (CC) on endothelial and platelet function in the short term (2 h after ingestion of a chocolate bar) and long term (4 weeks, two chocolate bars/day). Endothelial function was assessed non-invasively by flow-mediated vasodilatation of the brachial artery. Flow-mediated vasodilatation significantly improved from 4.98 ± 1.95 to 5.98 ± 2.32 (P = 0.045 and 0.02 for between-group changes) 2h after intake of FRC to 6.86 ± 1.76 after 4 weeks of daily intake (P = 0.03 and 0.004 for between groups). No effect on endothelial-independent vasodilatation was observed. Platelet adhesion significantly decreased from 3.9 ± 1.3 to 3.0 ± 1.3 (P = 0.03 and 0.05 for between groups) 2 h after FRC, an effect that was not sustained at 2 and 4 weeks. Cocoa-liquor-free CC had no effect, either on endothelial function or on platelet function. Blood pressure and heart rate did not change in either group. Conclusion Flavanol-rich chocolate acutely improves vascular function in patients with CHF. A sustained effect was seen after daily consumption over a 4-week period, even after 12 h abstinence. These beneficial effects were paralleled by an inhibition of platelet function in the presence of FRC only. © 2012 The Author.
Wieten L.,University Utrecht |
Van Der Zee R.,University Utrecht |
Goedemans R.,University Utrecht |
Sijtsma J.,University Utrecht |
And 4 more authors.
Cell Stress and Chaperones | Year: 2010
Stress proteins such as heat shock proteins (Hsps) are up-regulated in cells in response to various forms of stress, like thermal and oxidative stress and inflammation. Hsps prevent cellular damage and increase immunoregulation by the activation of anti-inflammatory Tcells. Decreased capacity for stress-induced Hsp expression is associated with immune disorders. Thus, therapeutic boosting Hsp expression might restore or enhance cellular stress resistance and immunoregulation. Especially food- or herb-derived phytonutrients may be attractive compounds to restore optimal Hsp expression in response to stress. In the present study, we explored three readout systems to monitor Hsp70 expression in a manner relevant for the immune system and evaluated novel Hsp co-inducers. First, intracellular staining and analysis by flow cytometry was used to detect stress and/or dietary compound induced Hsp70 expression in multiple rodent cell types efficiently. This system was used to screen a panel of food-derived extracts with potent anti-oxidant capacity. This strategy yielded the identity of several new enhancers of stressinduced Hsp70 expression, among them carvacrol, found in thyme and oregano. Second, CD4+ T-cell hybridomas were generated that specifically recognized an immunodominant Hsp70 peptide. These hybridomas were used to show that carvacrol enhanced Hsp70 levels increased T-cell activation. Third, we generated a DNAJB1-luc-O23 reporter cell line to show that carvacrol increased the transcriptional activation of a heat shock promoter in the presence of arsenite. These assay systems are generally applicable to identify compounds that affect the Hsp level in cells of the immune system. © Cell Stress Society International 2009.
Serafini M.,Antioxidant Research Laboratory |
Peluso I.,Antioxidant Research Laboratory |
Raguzzini A.,Antioxidant Research Laboratory
Proceedings of the Nutrition Society | Year: 2010
Epidemiological evidence suggests that a high intake of plant foods is associated with lower risk of chronic diseases. However, the mechanism of action and the components involved in this effect have not been identified clearly. In recent years, the scientific community has agreed to focus its attention on a class of secondary metabolites extensively present in a wide range of plant foods: the flavonoids, suggested as having different biological roles. The anti-inflammatory actions of flavonoids in vitro or in cellular models involve the inhibition of the synthesis and activities of different pro-inflammatory mediators such as eicosanoids, cytokines, adhesion molecules and C-reactive protein. Molecular activities of flavonoids include inhibition of transcription factors such as NF-B and activating protein-1 (AP-1), as well as activation of nuclear factor-erythroid 2-related factor 2 (Nrf2). However, the in vitro evidence might be somehow of limited impact due to the non-physiological concentrations utilized and to the fact that in vivo flavonoids are extensively metabolized to molecules with different chemical structures and activities compared with the ones originally present in the food. Human studies investigating the effect of flavonoids on markers of inflammation are insufficient, and are mainly focused on flavonoid-rich foods but not on pure molecules. Most of the studies lack assessment of flavonoid absorption or fail to associate an effect on inflammation with a change in circulating levels of flavonoids. Human trials with appropriate placebo and pure flavonoid molecules are needed to clarify if flavonoids represent ancillary ingredients or key molecules involved in the anti-inflammatory properties of plant foods. Copyright © 2010 The Authors.
PubMed | Antioxidant Research Laboratory
Type: Journal Article | Journal: Current pharmaceutical design | Year: 2012
An emerging role of IL-17 in the inflammatory response associated with pathogenesis of neurodegeneration has been recently suggested. However, though diet represents a key factor in the modulation of inflammatory processes, evidence is not currently available on the nutritional regulation of IL-17 in humans. In a double blind, randomized, placebo controlled, crossover study, we investigated the effect of High Fat Meal (HFM) on IL-17 circulating levels in presence of a placebo (HFM-P) or with a Fruit Juice Drink (HFM-FJD) composed of pineapple, blackcurrant and plum in fourteen healthy overweight humans. Fasting in the morning subjects ingested a test meal providing 1344 Kcal. Ingestion of HFM-P induced an inflammatory response mediated by TNF- (p < 0.001), IL-6 (p < 0.001) and IL-17 (p < 0.01). Plasma IL-17 concentration significantly increased at 1 h (+2.6 1.1 pg/ml), remaining high at 4 h (+2.98 1.2 pg/ml), 6 h (+2.38 0.6 pg/ml) and 8 h (+2.8 0.9 pg/ml) (ANOVA for time-course p=0.009). When the HFM was consumed in the presence of the FJD a marked inhibition of IL-17 response to the HFM was observed (ANOVA between treatment p=0.037). We provided, for the first time, evidence on the role of diet in modulating IL-17 production in healthy overweight subjects.