Effect of Walnut-Enriched Restructured Meat in the Antioxidant Status of Overweight/Obese Senior Subjects with at Least One Extra CHD-Risk Factor

Departamento de Nutrición y Bromatologia I (Nutrición), Facultad de Farmacia, Universidad Complutense, E-28040-Madrid, Spain.
Journal of the American College of Nutrition (Impact Factor: 1.45). 06/2007; 26(3):225-32. DOI: 10.1080/07315724.2007.10719605
Source: PubMed


A number of recent studies indicate that antioxidants reduce the oxidative stress associated with the development of coronary heart diseases (CHD).
(i) To investigate whether the erythrocyte catalase (CAT), superoxide dismutase (SOD), total glutathione, reduced glutathione (GSH), oxidized glutathione (GSSG), and lipid peroxidation (LPO), and serum uric acid and paraoxonase-1 (PON1) are modified at increased CHD-risk individuals consuming walnut-enriched meat (WM), (ii) to evaluate whether these changes were influenced by basal serum cholesterol, body mass index or smoking habit.
The study was a non blinded, cross-over, placebo-controlled trial in which 22 volunteers (60% overweight and 40% obese) with increased CHD-risk were randomly assigned to receive WM or control meat (CM) during two different periods of 5 weeks.
A significant interaction time*treatment (p < 0.05) was observed in all enzymes and substrates tested except HDL-C, uric acid and LPO. The treatment significantly increased CAT activity, total glutathione and GSSG (p < 0.05). Significant gender*time*treatment interaction (p = 0.043) for total glutathione was found increasing at the end of the WM period in male but not changing in female. Total glutathione and GSH/GSSG ratio (p < 0.05) were lower in smokers. Hypercholesterolemics presented higher uric acid (p < 0.05) but no enzyme activities or substrate concentrations were different from those of normocholesterolemics.
The WM tested appears to be a functional food as it improved the antioxidant status of increased CHD-risk volunteers. Despite its high energy content, it also appears adequate for overweight and obese people because did not exert negative effect upon body weight.

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Available from: Meritxell Nus, Feb 16, 2015
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    • "The literature indeed shows high bio-availability of the antioxidants in walnuts [51], and increased levels of TEAC in plasma after walnut consumption [37]. The antioxidant polyphenolics of walnuts (estimated 16–18 mg/g) appear to be a complex mixture, which has only partly been characterized with as main constituents, ellagic acid, ellagitannins, gallic acid and hydrocinnamic acids like chlorogenic acid [52] [53]. Likely, these components contribute to the increased plasma antioxidant capacity , seen in the present study. "
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