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排序方式: 共有491条查询结果,搜索用时 15 毫秒
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Michelle A. Phillips Caroline E. Childs Philip C. Calder Peter J. Rogers 《International journal of molecular sciences》2015,16(10):24600-24613
Findings from epidemiological and observational studies have indicated that diets high in omega-3 polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may reduce the risk of cognitive decline and Alzheimer’s disease (AD). To determine if increasing intake of DHA and EPA through supplementation is beneficial to cognition and mood in individuals with cognitive impairment no dementia (CIND) or Alzheimer’s disease (AD) a four month, randomised, double-blind, placebo controlled study was conducted. Fifty-seven participants with CIND and nineteen with AD were randomised to receive either omega-3 PUFAs (600 mg EPA and 625 mg DHA per day) or placebo (olive oil) over a four month period. Elevating depleted levels of EPA and DHA through supplementation in individuals with CIND or AD was found to have negligible beneficial effect on their cognition or mood. These findings confirm an overall negligible benefit of omega-3 PUFA supplementation for those with cognitive impairment and dementia. More intervention studies need to be undertaken with longer study durations and larger sample sizes. It may prove fruitful to examine effects of different doses as well as effects in other dementia subtypes. 相似文献
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Carlotta Lassandro Giuseppe Banderali Giovanni Radaelli Elisa Borghi Francesca Moretti Elvira Verduci 《International journal of molecular sciences》2015,16(8):19989-20000
Prevalence of metabolic syndrome is increasing in the pediatric population. Considering the different existing criteria to define metabolic syndrome, the use of the International Diabetes Federation (IDF) criteria has been suggested in children. Docosahexaenoic acid (DHA) has been associated with beneficial effects on health. The evidence about the relationship of DHA status in blood and components of the metabolic syndrome is unclear. This review discusses the possible association between DHA content in plasma and erythrocytes and components of the metabolic syndrome included in the IDF criteria (obesity, alteration of glucose metabolism, blood lipid profile, and blood pressure) and non-alcoholic fatty liver disease in obese children. The current evidence is inconsistent and no definitive conclusion can be drawn in the pediatric population. Well-designed longitudinal and powered trials need to clarify the possible association between blood DHA status and metabolic syndrome. 相似文献
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Inclusion of flaxseed in turkey diets decreases the n‐6/n‐3 PUFA ratio and increases the proportion of biologically active EPA and DHA without affecting meat quality 下载免费PDF全文
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Raquel Martín-Venegas M.Teresa Brufau Ana Maria Guerrero-Zamora Yves Mercier Pierre-André Geraert Ruth Ferrer 《Food chemistry》2013
dl-2-hydroxy-(4-methylthio)butanoic acid (HMTBA) is a source of dietary methionine (Met) that is widely used in poultry nutrition. We have previously shown that HMTBA is preferentially diverted to the transsulfuration pathway, which gives antioxidant metabolites such as taurine and glutathione. Therefore, here we hypothesize that this Met source can protect epithelial barrier function in an in vitro model of intestinal inflammation of Caco-2 cells. The results show that HMTBA prevents the increase in paracellular permeability induced by H2O2 or tumour necrosis factor-α. This effect can be attributed to the increased production of taurine and reduced glutathione. Similar results were obtained for dl-Met, although the protective role of the amino acid was less pronounced than that of the hydroxy analogue. In conclusion, the diversion to the transsulfuration pathway means that this Met precursor is of greater value than previously thought, due to its capacity to improve intestinal homeostasis and the quality of poultry products destined for human consumption. 相似文献
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Gerardo Navarro-García Juan C. Ramírez-Suárez Elizabeth Cota-Quiñones Fernando Márquez-Farías Lorena Bringas-Alvarado 《Food chemistry》2010
The effect of storage time on the quality of liver oil from two commercial rajiform species (Rhinoptera bonasus and Aetobatus narinari) captured in the Gulf of Mexico (State of Campeche coast line) was evaluated. Oil characterisation was conducted by physical (specific gravity, saponification index and water content) and chemical analyses (fatty acid content, carotenes and tocopherols) whilst storage stability (peroxide value, free fatty acids, conjugated dienes, anisidine value and changes in docosahexaenoic acid, DHA and content) was studied for 87 days at 25 °C. Increases (p < 0.05) in free fatty acids, conjugated dienes, peroxide value and anisidine value, and a decrease (p < 0.05) in DHA were observed during the storage time for both oil species as oxidation proceeded. It was concluded that R. bonasus and A. narinari oils lasted for 52 and 66 days under these storage conditions, respectively. 相似文献
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Moderate red wine consumption is associated with decreased risk for cardiovascular disease; however, the underlying mechanisms are not completely understood. The main aim of this study was to investigate the effects of red wine polyphenols (WP) on the oxidizability of human plasma fatty acids, in particular those most involved in the inflammatory response — archidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The oxidizability of the major fatty acids of plasma was determined by measuring their loss gaschromatographycally during peroxidation kinetics induced by 2′-azobis(2-methylpropionamidine)-dihydrochloride. The capacity of WP to scavenge 1,1,diphenyl-2-picryl-hydrazyl (DPPH), superoxide anion and hydroxyl radicals, and trap total peroxyl radicals in plasma (TRAP) was also measured. WP (1.75–5 μg/mL) inhibited DPPH, superoxide anion and hydroxyl radicals and increased TRAP in a dose-dependent manner. WP (1.75 μg/mL) significantly protected all plasma PUFA from peroxidation but the protection of EPA and DHA was higher than that of AA. These results suggest that the association of WP to apolipoproteins makes EPA and DHA less accessible to hydro-soluble radicals than AA, thus providing a biochemical rationale for future ‘in vivo’ studies on the benefits to health of moderate red wine consumption. 相似文献
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Food enrichment with nutraceuticals is an important goal, but its effectiveness in preventing diseases depends on preserving the functionality and bioavailability of the bioactive nutraceuticals. Omega-3 polyunsaturated fatty acids, such as docosahexaenoic acid (DHA), are important nutraceutical lipids, providing protection against cardiovascular and other diseases. Caseins are the major milk proteins whose biological function is to transport calcium, protein and phosphate from mother to the neonate. Our goal was to harness the natural self-assembly properties of caseins for protecting and delivering this important, but sensitive nutraceutical, DHA. Using spectrofluorescence we have shown, apparently for the first time, that casein can bind DHA with a relatively high affinity (Kb = (8.38 ± 3.12) × 106 M−1), and the binding ratio was 3–4 DHA molecules per protein molecule on average. Moreover, DLS particle characterization experiments have shown the formation of nanoparticles upon addition of DHA (predissolved in ethanol) to a casein solution. When calcium and phosphate were added (at 4 °C), DHA-loaded re-formed casein micelles (r-CM) with a size of 50–60 nm were obtained and there was no significant effect of the thermal treatment (74 °C, 20 s) on particle size. When casein nanoparticles (CNP) were prepared (at room temperature and without adding calcium and phosphate), DHA-loaded CNP with a diameter of 288.9 ± 9.6 nm were formed. Both the DHA-loaded r-CM and the DHA-loaded CNP systems showed a remarkable protective effect against DHA oxidation, demonstrating good colloidal stability and bioactive conservation throughout shelf life at 4 °C. These nanotechnologies may enable the enrichment of foods and beverages for promoting health of wide populations. 相似文献