Recent epidemiologic studies have associated nut consumption with a reduced incidence of cardiovascular mortality. However, little is known about the contribution of nut polyphenols to antioxidant and cardiovascular protection. In this investigation, polyphenol-rich extracts from English walnuts (Juglans regia) were studied and compared with ellagic acid for their ability to inhibit in vitro plasma and LDL oxidation, as well as their effects on LDL α-tocopherol during oxidative stress. In addition, the Trolox equivalent antioxidant activity (TEAC) was determined and liquid chromatography electrospray detection mass spectrometry (LC-ELSD/MS) analyses of the walnut extracts were performed. 2,2′-Azobis′(2-amidino propane) hydrochloride (AAPH)-induced LDL oxidation was significantly inhibited by 87 and 38% with the highest concentration (1.0 μmol/L) of ellagic acid and walnut extract, respectively. In addition, copper-mediated LDL oxidation was inhibited by 14 and 84% in the presence of ellagic acid and walnut extract, respectively, with a modest, significant LDL α-tocopherol sparing effect observed. Plasma thiobarbituric acid reacting substance (TBARS) formation was significantly inhibited by walnut extracts and ellagic acid in a dose-dependent manner, and the extracts exhibited a TEAC value greater than that of α-tocopherol. LC-ELSD/MS analysis of the walnut extracts identified ellagic acid monomers, polymeric ellagitannins and other phenolics, principally nonflavonoid compounds. These results demonstrate that walnut polyphenolics are effective inhibitors of in vitro plasma and LDL oxidation. The polyphenolic content of walnuts should be considered when evaluating their antiatherogenic potential.
1 February 2003 in Journal of the American Dietetic Association
Background: Controversy exists about the ability of soy protein and isoflavones to modulate vascular reactivity and biochemical cardiovascular disease risk markers in healthy, normolipidemic postmenopausal women. Objective: The objective was to investigate whether the consumption of soy protein with isoflavones would result in improved vascular reactivity and decreased biochemical markers of endothelial dysfunction and inflammation, independent of enhanced lipid and antioxidant effects. Design: Healthy postmenopausal women (n = 28) were enrolled in a randomized, double-blind, crossover study, and they consumed 25 g of 3 protein products/d for 6 wk each, with intervening washout periods. The products were isolated soy protein with isoflavones, ethanol-washed isolated soy protein with trace isoflavones, and total milk protein, which supplied 107, 2, and 0 mg total isoflavone (aglycone) units/d, respectively. We studied vascular function by using brachial artery reactivity values, plasma concentrations of vasoactive factors, endothelial inflammatory markers, and plasma isoflavone concentrations. The resistance of whole plasma and isolated LDL to copper-mediated oxidation was measured by conjugated diene formation. Results: Postocclusion peak flow velocity of the brachial artery was significantly (P = 0.03) lower after treatment with isolated soy protein with isoflavones, which is consistent with a vasodilatory response, than after treatment with total milk protein. Plasma isoflavones and metabolites were significantly (P < 0.01) higher after treatment with isolated soy protein with isoflavones. There were no significant changes in biochemical cardiovascular disease risk markers or conjugated diene formation between the 3 dietary groups. Conclusion: Daily consumption of soy protein with isoflavones can result in positive vascular effects that are independent of lipid and antioxidant effects in healthy postmenopausal women.
Heart failure (HF) is a major health care burden increasing in prevalence over time. Effective, evidence-based interventions for HF prevention and management are needed to improve patient longevity, symptom control, and quality of life. Dietary Approaches to Stop Hypertension (DASH) diet interventions can have a positive impact for HF patients. However, the absence of a consensus for comprehensive dietary guidelines and for pragmatic evidence limits the ability of health care providers to implement clinical recommendations. The refinement of medical nutrition therapy through precision nutrition approaches has the potential to reduce the burden of HF, improve clinical care, and meet the needs of diverse patients. The aim of this review is to summarize current evidence related to HF dietary recommendations including DASH diet nutritional interventions and to develop initial recommendations for DASH diet implementation in outpatient HF management. Articles involving human studies were obtained using the following search terms: Dietary Approaches to Stop Hypertension (DASH diet), diet pattern, diet, metabolism, and heart failure. Only full-text articles written in English were included in this review. As DASH nutritional interventions have been proposed, limitations of these studies are the small sample size and non-randomization of interventions, leading to less reliable evidence. Randomized controlled interventions are needed to offer definitive evidence related to the use of the DASH diet in HF management.
1 February 2003 in Experimental Biology and Medicine
Growth, reproductive performance, and indices of collagen maturation and expression were investigated in Balb/c mice fed chemically defined, amino acid-based diets with or without the addition 6 <M pyrroloquinoline quinone (PQQ)/kg diet. The diets were fed to virgin mice for 8 weeks before breeding. At weaning, the pups from successful pregnancies were fed the same diet as their respective dams. Reproductive performance was compromised in mice fed diets devoid of PQQ, and their offspring grew at slower rates than offspring from mice fed diets supplemented with PQQ. Successful mating (confirmed vaginal plugs) was not affected by the presence or absence of PQQ; however, pup viability (number of pups at parturition/number of pups at Day 4 of lactation) was decreased in PQQ-deprived mice. Conception (percentage of females giving live births) and fertility (percentage of births) were also decreased in PQQ-deprived mice. The slower rates of growth in offspring from PQQ-deprived mice were associated with decreased steady-state mRNA levels for Type I procollagen α1-chains in skin and lungs from neonatal mice. Values for lysyl oxidase accumulation as protein in PQQ-deficient mice also tended to be lower than corresponding values from PQQ-supplemented or -replete mice. Skin collagen solubility was increased in PQQ-deprived mice. These results indicate that PQQ supplementation can improve reproductive performance, growth, and may modulate Indices of neonatal extracellular matrix production and maturation in mice fed chemically defined, but otherwise nutritionally complete diets.