Olive polyphenol effects in a mouse model of chronic ethanol addiction

Objectives Alcohol addiction elicits oxidative imbalance and it is well known that polyphenols possess antioxidant properties. We investigated whether or not polyphenols could confer a protective potential against alcohol-induced oxidative stress. Methods We administered (per os) for two months 20 mg/kg of olive polyphenols containing mostly hydroxytyrosol in alcoholic adult male mice. Hydroxytyrosol metabolites as hydroxytyrosol sulfate 1 and hydroxytyrosol sulfate 2 were found in the serum of mice administered with polyphenols with the highest amount in animals treated with both polyphenols and alcohol. Oxidative stress was evaluated by FORT (free oxygen radical test) and FORD (free oxygen radical defense) tests. Results Alcoholic mice showed a worse oxidative status than nonalcoholic mice (higher FORT and lower FORD) but polyphenol supplementation partially counteracted the alcohol pro-oxidant effects, as evidenced by FORT. Conclusions A better understanding of the antioxidant protection provided by polyphenols might be of primary interest for drug discovery and dietary-based prevention of the damage associated with chronic alcohol abus

Protective Activity of Broccoli Sprout Juice in a Human Intestinal Cell Model of Gut Inflammation

Benefits to health from a high consumption of fruits and vegetables are well established and have been attributed to bioactive secondary metabolites present in edible plants. However, the effects of specific health-related phytochemicals within a complex food matrix are difficult to assess. In an attempt to address this problem, we have used elicitation to improve the nutraceutical content of seedlings of Brassica oleracea grown under controlled conditions. Analysis, by LC-MS, of the glucosinolate, isothiocyanate and phenolic compound content of juices obtained from sprouts indicated that elicitation induces an enrichment of several phenolics, particularly of the anthocyanin fraction. To test the biological activity of basal and enriched juices we took advantage of a recently developed in vitro model of inflamed human intestinal epithelium. Both sprouts’ juices protected intestinal barrier integrity in Caco-2 cells exposed to tumor necrosis factor under marginal zinc deprivation, with the enriched juice showing higher protection. Multivariate regression analysis indicated that the extent of rescue from stress-induced epithelial dysfunction correlated with the composition in bioactive molecules of the juices and, in particular, with a group of phenolic compounds, including several anthocyanins, quercetin-3-Glc, cryptochlorogenic, neochlorogenic and cinnamic acids

Identification and quantification of glucosinolates in different tissues of Raphanus raphanistrum by liquid chromatography tandem-mass spectrometry

This study aims to identify and quantify the glucosinolates from different parts of wild radish R. raphanistrum (leaves, flowers, fruits, roots) using liquid chromatography-tandem mass spectrometry. Glucoraphenin is the predominant compound, accounting for about 87% (w/w) of total glucosinolate content, followed by glucobrassicin, glucoraphasatin and glucoraphanin (153 mg 100 g−1, 149 mg 100 g−1 and 141 mg 100 g−1 FW, respectively) in fruits; followed by glucoraphasatin (3 mg 100 g−1 FW) in flowers and by glucobrassicin, 4-hydroxyglucobrassicin and glucoraphasatin (145 mg 100 g−1, 27 mg 100 g−1 and 24 mg 100 g−1 FW, respectively) in leaves. In roots the major glucosinolate is glucoraphasatin (56 mg 100 g−1 FW) followed by the glucoraphenin and methoxyglucobrassicin (16 mg 100 g−1 and 7 mg 100 g−1 FW, respectively). Principal component analysis allowed the discrimination of fruit samples from other parts of the plant for the majority of glucosinolates and the fruits are highlighted as sources of glucosinolates. The results are interesting given that wild radish is one of the most important weeds of crops in the Mediterranean region and is popular for home vegetable production and for its employment in human nutrition both as a food as well as for medicinal purposes

Oxidative stress inhibition by resveratrol in alcohol dependent mice

Objective uncontrolled ingestion of alcohol has dramatic consequences on the entire organism also associated with the oxidation process induced by alcohol by elevating radical oxygen species (ROS). Resveratrol, a non-flavonoid phenol, shows well-documented antioxidant properties. We investigated the potential antioxidant ability of this natural compound in a mouse model of alcohol addiction. Methods we administered (per os) for two months 10 mg/kg/day of resveratrol in alcoholic adult male mice. Oxidative stress was evaluated by measuring serum free oxygen radicals defense (FORD) and free oxygen radicals (FORT) levels. Resveratrol metabolites were measured in the serum of mice administered with resveratrol. Finally, the effect of resveratrol on alcohol-induced alteration of BDNF in the liver was investigated. Results prolonged consumption of resveratrol strongly counteracts serum ROS formation caused by chronic alcohol intake, without effects on natural, free oxygen radical defense. The presence of resveratrol metabolites only in the serum of animals supplemented with resveratrol potentiates the evidence that the antioxidant effect observed is due to the ingestion of the natural compound. Moreover, resveratrol supplementation can counteract alcohol-induced BDNF elevation in the liver, the main target of organ alcohol-induced damage. Conclusion the consumption of resveratrol through metabolite formation may play a protective role, by decreasing free radical formation, and by modulating BDNF involved in hepatic disruption induced by chronic alcohol consumption. Further investigation about the mechanism underlying the protective effect could reinforce the potential use of resveratrol as a dietary supplement to prevent damage associated with chronic alcohol abuse

TNF-a and IL-10 modulation induced by polyphenols extracted by olive pomace in a mouse model of paw inflammation

Polyphenols from olive are known to possess antioxidant and anti-inflammatory properties. The aim of this study was to study whether or not administration of olive (Olea europaeaL.) polyphenols could have an effect on cytokines as TNF-a and IL-10 in the mouse paw following inflammation induced by carrageenan injection. TNF-a and IL-10 were measured by enzyme-linked immunosorbent assay. Carrageenan decreased IL-10 in the paws, however, this reduction appeared to be less evident in mice treated with carrageenan but administered with polyphenols. As for TNF-a, our findings did not reveal differences between groups but an increase in polyphenol and carrageenan groups if compared to the carrageenan only group. No differences between groups in the serum Glutathione were found. Altogether, this investigation shows that olive polyphenols in the mouse may modulate the levels of cytokines having a role in the process of inflammation as TNF-a and IL-10

The Fate of Chlorophylls in Alkali-Treated Green Table Olives: A Review

This paper reviews the current knowledge regarding modifications to chlorophylls during the processing of green table olives treated with alkali. Particular attention is given to the pheophytinization reactions (substitution of Mg2+ by 2H+ in the chlorophyll chromophore group) that can take place because of pH and/or temperature changes and the possible sequential substitution of the 2H+ with Cu2+ within the chlorophyll porphyrin ring. These reactions may have a direct impact on the commercial value of olive productions as some naturally forming Cu–chlorophylls complexes (i) are identical to strictly forbidden colorants for table olives (E141) and (ii) have been identified as responsible for the unwelcome appearance of the so-called green staining alteration (characterized by bluish-green zones distributed over the olive skin of the drupes)

Metabolic transformation of apple polyphenols in human body

Rationale: Fruit and vegetables are claimed to have beneficial effect on human health mostly due to their high polyphenol (PP) content. (1) Regular consumption is protective against age related diseases and different forms of cancer (2). As PP are largely metabolized both by the human organism and gut microbiota, identification of the forms of metabolites and the kinetics of their appearance into the circulation is essential for understanding their possible bioactivity in humans. Methods: In order to evaluate absorption and transformation of apple polyphenols, a human single-dose crossover controlled blind experiment was designed. In 2 different sessions 12 subjects were supplemented with apple juice (1 g/l total PF) or polyphenol enriched apple juice (4 g/l total PF). Urine and plasma samples were collected at different time points and analyzed using an untargeted metabolomics approach. Results: Scarcely metabolized polyphenols were recognized as potential biomarkers. These compounds showed two different kinetic patterns. Epicatechin methyl sulfate, ferulic acid sulfate and phloretin glucuronide reached their maximal concentration 1 hour after apple juice supplementation. While, the methyl, sulfate and glucuronide conjugates of valerolactons had their peak concentration 5 hours after the supplementation. The concentration of the majority of the biomarkers showed an increase four times greater in high PP diet than in low. Conclusion: Untargeted metabolomics allowed identification of biomarkers of apple consumption and demonstrated that an increase in polyphenol intake corresponds to an increase of circulating metabolites within the limits of ‘normal’ consumption. Thus, if the beneficial effects of these compounds are confirmed, it might prove beneficial to increase their plasma concentration by increasing their intake or choosing polyphenols richer food

Total antioxidant capacity as a tool to assess redox status: critical view and experimental data

The measure of antioxidant capacity (AC) considers the cumulative action of all the antioxidants present in plasma and body fluids, thus providing an integrated parameter rather than the simple sum of measurable antioxidants. The capacity of known and unknown antioxidants and their synergistic interaction is therefore assessed, thus giving an insight into the delicate balance in vivo between oxidants and antioxidants. Measuring plasma AC may help in the evaluation of physiological, environmental, and nutritional factors of the redox status in humans. Determining plasma AC may help to identify conditions affecting oxidative status in vivo (e.g., exposure to reactive oxygen species and antioxidant supplementation). Moreover, changes in the plasma AC after supplementation with galenic antioxidants or with antioxidant-rich foods may provide information on the absorption and bioavailability of nutritional compounds. Consequently, this review discusses the rationale, interpretation, confounding factors, measurement limits, and human applications of the measure of plasma AC