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1.
Endothelial dysfunction is associated with atherogenesis and oxidative stress in humans. In rat and rabbit blood vessels, wine polyphenol antioxidants induce vascular relaxationin vitro through the NO-cGMP pathway. To assess the effect of a regular high-fat diet (HFD) and moderate red wine consumption on endothelial function (EF), a study was performed in healthy male volunteers. EF was measured as flow-mediated dilatation of the brachial artery, employing high-resolution ultrasound after an overnight fast. Other clinical and biochemical parameters related to EF were also measured. Six volunteers received a control diet, rich in fruits and vegetables (27% calories as fat) and five volunteers received an HFD (39.5% calories as fat). Measurements were done twice on each volunteer: after a period of 30 d with diet plus 240 mL of red wine/d, and after a period of 30 d with diet, without wine. In the absence of wine, there is a reduction of EF with HFD when compared to the control diet (P=0.014). This loss of EF is not seen when both diets are supplemented with wine for 30 d (P=0.001). Plasma levels ofn−3 fatty acids (R 2=0.232,P=0.023) and lycopene (R 2=0.223,P=0.020) show a positive correlation with individual EF measurements, but they do not account for the significant differences observed among dietary groups or after wine supplementation. These results help elucidate the deleterious effect of a high-fat diet and the protective role of wine, n−3 fatty acids and dietary antioxidants in cardiovascular disease.  相似文献   

2.
Oxidative modification of low density lipoprotein (LDL) is involved in the pathogenesis of atherosclerosis and coronary heart disease, which are low in the Mediterranean area possibly due to a high dietary proportion of plant food. Ethanolic extracts were prepared from more than 120 Mediterranean edible plants collected in remote areas (which maintain their tradional diet) and their antioxidant potential was studied. Extracts derived from Agaricus campestris, Cyana cardunculus, Thymus pulegioides, and Vicia faba were subjected to further analysis in this study. The extracts' potential to scavenge the DPPH radical (2,2-diphenyl-1-picrylhydrazyl radical) and hypochlorous acid (HOCl), as well as their antioxidant capacity, was comparable to the those obtained for standard antioxidants (e.g., quercetin, Trolox), Myeloperoxidase (MPO) catalyzes the production of the highly chlorinating and oxidizing agent HOCl, which reacts with the LDL apoprotein moiety, leading to the derivatization of its aminoacidic residues. Coincubation with extracts significantly prevented HOCl-induced modification of the LDL residue tryptophan, whereas higher concentrations were required to retard lysine damage. Moreover, the extracts inhibited MPO-catalyzed guaiacol oxidation in a concentration-dependent manner in a cell-free assay but, in contrast, did not affect MPO activity in isolated human neutrophils. MPO is also known to facilitate nitric dioxide oxidation. The formation of 3-nitrotyrosine was significantly lower in bovine endothelial aortic cells incubated with C. cardunculus or T. pulegioides. In synthesis, our study shows that local Mediterranean plant foods prevent HOCI toxicity in vitro and, thus suggests further mechanisms responsible for the reported health-beneficial effect of the Mediterranean diet.  相似文献   

3.
Over 50 years of research has sought to define the role dietary fat plays in cardiovascular disease (CVD) risk. Although optimal dietary fat quantity has been keenly pursued over past decades, attention has recently centered on the value of dietary fat quality. The purpose of the present review is to provide a critical assessment of the current body of evidence surrounding efficacy of dietary monounsaturated fatty acids (MUFA) for reduction of traditional risk factors defining metabolic syndrome (MetS) and CVD. Due to existing and emerging research on health attributes of MUFA rich diets, and to the low prevalence of chronic disease in populations consuming MUFA rich Mediterranean diets, national dietary guidelines are increasingly recommending dietary MUFA, primarily at the expense of saturated fatty acids (SFA). Consumption of dietary MUFA promotes healthy blood lipid profiles, mediates blood pressure, improves insulin sensitivity and regulates glucose levels. Moreover, provocative newer data suggest a role for preferential oxidation and metabolism of dietary MUFA, influencing body composition and ameliorating the risk of obesity. Mounting epidemiological and human clinical trial data continue to demonstrate the cardioprotective activity of the MUFA content of dietary fat. As the debate on the optimal fatty acid composition of the diet continues, the benefit of increasing MUFA intakes, particularly as a substitute for dietary SFA, deserves considerable attention.  相似文献   

4.
It is commonly accepted that oxidized low-density lipoprotein (ox-LDL) plays an important role in coronary heart disease (CHD) and etiologically related atherogenesis. Consumption of wine may contribute to the low risk of CHD in the Mediterranean population. These findings raise the question of the in vivo antioxidant role of wine phenolic compounds after a prolonged supplementation period in healthy human volunteers. We found that subjects, receiving 2 g/d of an alcohol-free red wine-extracted phenolic compound (RWPC) mixture for 14 d (which was equivalent to about 1 L/d of the red wine), exhibited an increase in the plasma antioxidative capacity and in LDL vitamin E by blood sampling under fasting conditions. The fact that the LDL Cu2+-oxidizability was not decreased can be explained by both the lack of phenolic compound affinity for the lipoprotein particle, highlighted by LDL dialysis, and the insufficient increase in LDL vitamin E, as shown by the relationship between vitamin E content and oxidation resistance of LDL evidenced by literature data. These results support that RWPC could play a coantioxidant role, similar to that of vitamin C, possibly accounting for their LDL vitamin E sparing effect and their beneficial role in lowering CHD risks.  相似文献   

5.

Background

A plant-based diet protects against chronic oxidative stress-related diseases. Dietary plants contain variable chemical families and amounts of antioxidants. It has been hypothesized that plant antioxidants may contribute to the beneficial health effects of dietary plants. Our objective was to develop a comprehensive food database consisting of the total antioxidant content of typical foods as well as other dietary items such as traditional medicine plants, herbs and spices and dietary supplements. This database is intended for use in a wide range of nutritional research, from in vitro and cell and animal studies, to clinical trials and nutritional epidemiological studies.

Methods

We procured samples from countries worldwide and assayed the samples for their total antioxidant content using a modified version of the FRAP assay. Results and sample information (such as country of origin, product and/or brand name) were registered for each individual food sample and constitute the Antioxidant Food Table.

Results

The results demonstrate that there are several thousand-fold differences in antioxidant content of foods. Spices, herbs and supplements include the most antioxidant rich products in our study, some exceptionally high. Berries, fruits, nuts, chocolate, vegetables and products thereof constitute common foods and beverages with high antioxidant values.

Conclusions

This database is to our best knowledge the most comprehensive Antioxidant Food Database published and it shows that plant-based foods introduce significantly more antioxidants into human diet than non-plant foods. Because of the large variations observed between otherwise comparable food samples the study emphasizes the importance of using a comprehensive database combined with a detailed system for food registration in clinical and epidemiological studies. The present antioxidant database is therefore an essential research tool to further elucidate the potential health effects of phytochemical antioxidants in diet.  相似文献   

6.
D. Kromhout 《Lipids》1999,34(1):S27-S31
Oxidized low density lipoproteins (LDL) play a major role in the development of atherosclerosis. Saturated fatty acids, especially fatty acids with 12–16 carbon atoms, are the most important determinants of the LDL cholesterol level. The LDL lipoprotein fraction can be oxidized by, e.g., smoking. Oxidative damage of LDL lipoproteins can be prevented by nutritive, e.g., vitamin E, and nonnutritive antioxidants, e.g., flavonoids. It can therefore be hypothesized that fatty acids and antioxidants are important determinants of coronary heart disease (CHD). There is a large body of evidence from prospective studies that LDL cholesterol-lowering is associated with a lower CHD risk. The evidence for a protective effect of antioxidants on CHD risk is much weaker and is most promising for vitamin E and flavonoids. The Seven Countries Study showed that at the population level saturated fat, cigarette smoking, and flavonoids are important determinants of long-term CHD mortality. These results suggest that a diet low in saturated fat and rich in antioxidants in combination with no smoking is associated with low CHD risk.  相似文献   

7.
In recent years, many nutrition news headlines exclaimed that saturated fat was not linked to heart disease, leaving the public confused about whether to limit intake, as has been the dietary recommendation for several decades. However, a more nuanced look at the evidence indicates that high saturated fat diets are in fact not benign with respect to heart disease risk. Dietary recommendations should emphasize replacing saturated fats typical in red and processed meats, and certain tropical oils and dairy forms, with healthier polyunsaturated and monounsaturated fat‐rich foods, such as nuts, olive oil, and fatty fish, as well as healthy sources of carbohydrates, such as fiber‐rich whole‐grain foods, rather than refined‐grain and sugar‐laden foods.  相似文献   

8.
Wahle KW  Caruso D  Ochoa JJ  Quiles JL 《Lipids》2004,39(12):1223-1231
Epidemiological studies show that populations consuming a predominantly plant-based Mediterranean-style diet exhibit lower incidences of chronic diseases than those eating a northern European or North American diet. This observation has been attributed to the greater consumption of fruits and vegetables and the lower consumption of animal products, particularly fat. Although total fat intake in Mediterranean populations can be higher than in other regions (ca. 40% of calories), the greater proportion is derived from olive oil and not animals. Increased olive oil consumption is implicated in a reduction in cardiovascular disease, rheumatoid arthritis, and, to a lesser extent, a variety of cancers. Olive oil intake also has been shown to modulate immune function, particularly the inflammatory processes associated with the immune system. Olive oil is a nonoxidative dietary component, and the attenuation of the in-flammatory process it elicits could explain its beneficial effects on disease risk since oxidative and inflammatory stresses appear to be underlying factors in the etiology of these diseases in man. The antioxidant effects of olive oil are probably due to a combination of its high oleic acid content (low oxidation potential compared with linoleic acid) and its content of a variety of plant antioxidants, particularly oleuropein, hydroxytyrosol, and tyrosol. It is also possible that the high oleic acid content and a proportionate reduction in linoleic acid intake would allow a greater conversion of α-linolenic acid (18∶3n−3) to longer-chain n−3 PUFA, which have characteristic health benefits. Adoption of a Mediterranean diet could confer health benefits in high-risk populations.  相似文献   

9.
Assessment of potential prooxidant and antioxidant actions   总被引:1,自引:0,他引:1  
Suggestions that oxidative stress plays a role in human diseases have led to the proposal that health might be improved by increased dietary intake of antioxidants. Plant-derived antioxidants, such as flavonoids or rosemary extracts, are increasingly proposed as important dietary antioxidant factors, and foods rich in antioxidants are also receiving attention. Before widescale usage of natural and synthetic antioxidants can be suggested, it is necessary to establish the properties of such molecules. Assays for characterizing the potential prooxidant/antioxidant actions of food additives, antioxidant supplements, antioxidant drug molecules, and nutrient components have been developed for this purpose. Based on a paper presented at the 86th AOCS Annual Meeting & Expo, San Antonio, Texas, May 1995.  相似文献   

10.
Diets must supply enough nitrogen and essential amino acids to satisfy human needs. A diet's protein quality is associated to its digestibility, amino acid composition, protein concentration and dietary and preparation factors that enhance or reduce essential amino acid and protein bioavailability. Dietary energy intake also affects the utilization efficiency of dietary proteins. Protein quality of Latin American diets varies between countries and between socioeconomic groups in a given country. Most poor and lower-middle income persons consume diets with strong predominance of vegetable proteins. These diets are usually bulky, with relatively low protein concentration and energy density, and sometimes do not provide enough of one or more essential amino acids. In some countries and in some population groups, over 50% of the dietary proteins are of animal origin. This may be a risk factor of cardiovascular disease. Protein quality of Latin American diets, however, can be improved by modifying the proportions of some foods in order to achieve amino acid complementation, increase protein concentration and, in some instances, increase digestibility. Examples of diets that are satisfactory for preschool children and adults are given. Nevertheless, improvement of the overall nutritional quality of the diets is of foremost importance, so that they may provide the energy and all essential nutrients required for humans.  相似文献   

11.
There is interest in incorporating lycopene into foods because it is a natural pigment and can also play a role in preventing disease. Therefore, the effect of the addition of various antioxidants in lycopene containing oil‐in‐water emulsions stabilized with Tween 20 at acidic pH was studied in order to determine protection systems against lycopene oxidation. In this model, EDTA showed pro‐oxidant activity while other chelators like citric acid and tripolyphosphate showed no effect. The free radical scavengers, propyl gallate (PG), gallic acid (GA), and α‐tocopherol all had the ability to decrease lycopene oxidation with α‐tocopherol being the most effective. The combination of 1 µM α‐tocopherol and 10 µM GA was more effective than the individual antioxidants. Addition of ascorbic acid to the combination of α‐tocopherol and GA system accelerated lycopene loss. These results suggest that by the proper selection of free radical scavenging antioxidants, lycopene stability in oil‐in‐water emulsions could be significantly improved. Practical applications: Evidence that dietary lycopene decreases the risk for a number of health conditions has generated new opportunities for addition of lycopene to functional foods. A successful strategy to deliver lycopene into foods is by means of oil‐in‐water emulsions. However, lycopene may decompose thus causing nutritional loss and color fading. In order to prevent this, the effectiveness of various antioxidants and their combinations in Tween 20 stabilized oil‐in‐water emulsions was studied. Overall, lycopene oxidation in oil‐in‐water emulsions could be significantly reduced by the proper selection of free radical scavengers. This fact is of interest to food industry for increasing the shelf‐life of lycopene containing functional foods where the lycopene is dispersed in the food in the form of an oil‐in‐water emulsion.  相似文献   

12.
Photo-activated plant secondary compounds have been shown to be toxic to many organisms including insects. Insect defenses include behavioral mechanisms such as light avoidance, as well as specific biochemical defenses such as antioxidants and antioxidant enzymes. These antioxidant defenses eliminate or quench the deleterious singlet oxygen and free radicals formed by these phototoxins. In this paper we examined the role of dietary antioxidants in protecting the phototoxin-sensitive insect herbivoreManduca sexta. Elevated dietary levels of the lipid-soluble antioxidants-carotene and vitamin E resulted in a concentration-dependent reduction in the mortality associated with treatment ofM. sexta larvae with the phototoxic thiophene-terthienyl. Elevated levels of dietary ascorbic acid had no effect, whereas reduced levels greatly increased the toxicity of-terthienyl. Tissue levels of antioxidants were shown to increase substantially in larvae fed antioxidant-supplemented diets. The results suggest that the ability to absorb and utilize plant-derived antioxidants could be an important defense against photo-activated plant secondary compounds and may have allowed some insects to exploit phototoxic plants.  相似文献   

13.
In developed countries atherosclerotic cardiovascular disease is the reason for about 50% of all deaths. With growing prosperity coronary heart disease (CHD) is becoming the major cause of premature death. Most complications of atherosclerosis occur unexpectedly and more than 50% of the patients developing a myocardial infarction do not survive more than one year. Because of the severe morbidity and high mortality primary prevention is likely to be the only solution. Epidemiological studies show a strong, positive relationship between plasma cholesterol concentrations and the incidence of CHD. People who immigrate from low‐risk to high‐risk areas usually acquire similar plasma cholesterol levels as the native population and a similar CHD risk. This demonstrates that environmental rather than genetic factors lead to the differences in cardiovascular risk and supports the notion that nutrition and lifestyle play a major role. The association between dietary intake of fat and cholesterol and the extent of atherosclerosis and CHD has been recognized in previous studies. The amount of saturated fat in the diet correlates stronger with the incidence of CHD than with total fat intake. The consumption of unsaturated fatty acids, however, appears to be beneficial, since it is inversely correlated with the plasma cholesterol concentration and risk of myocardial infarction. Lately additional nutritional factors like trans fatty acids with a negative influence on risk as well as positive factors like linolenic acid have attracted much attention. In conclusion, as a challenge to public health, preventive medicine needs to focus on changes in dietary habits with priority, particularly fat modification. A nutrition low in total fat primarily avoiding saturated and trans fatty acids, but rich in fruit and vegetables should be recommended.  相似文献   

14.
Partially hydrogenated oils (PHO) have been removed from the food supply due to adverse effects on risk for coronary heart disease (CHD). High-oleic soybean oils (HOSBO) are alternatives that provide functionality for different food applications. The objective of this study was to determine how consumption of diets containing HOSBO compared to other alternative oils, with similar functional properties, modifies LDL cholesterol (LDLc) and other risk factors and biomarkers of CHD. A triple-blind, crossover, randomized controlled trial was conducted in humans (n = 60) with four highly-controlled diets containing (1) HOSBO, (2) 80:20 blend of HOSBO and fully hydrogenated soybean oil (HOSBO+FHSBO), (3) soybean oil (SBO), and (4) 50:50 blend of palm oil and palm kernel oil (PO + PKO). Before and after 29 days of feeding, lipids/lipoproteins, blood pressure, body composition, and markers of inflammation, oxidation, and hemostasis were measured. LDLc, apolipoprotein B (apoB), NonHDL-cholesterol (HDLc), ratios of total cholesterol (TC)-to-HDLc and LDLc-to-HDL cholesterol, and LDL particle number and small LDL particles concentration were lower after HOSBO and HOSBO+FHSBO compared to PO (specific comparisons p < 0.05). Other than TC:HDL, there were no differences in lipid/lipoprotein markers when comparing HOSBO+FHSBO with HOSBO. LDLc and apoB were higher after HOSBO compared to SBO (p < 0.05). PO + PKO increased HDLc (p < 0.001) and apolipoprotein AI (p < 0.03) compared to HOSBO and HOSBO+FHSBO. With the exception of lipid hydroperoxides, dietary treatments did not affect other CHD markers. HOSBO, and blends thereof, is a PHO replacement that results in more favorable lipid/lipoprotein profiles compared to PO + PKO (an alternative fat with similar functional properties).  相似文献   

15.
Cardiovascular disease (CVD) is a leading cause of death worldwide. Elevated concentrations of serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) are major lipid biomarkers that contribute to the risk of CVD. Phytosterols well known for their cholesterol-lowering ability, are non-nutritive compounds that are naturally found in plant-based foods and can be classified into plant sterols and plant stanols. Numerous clinical trials demonstrated that 2 g phytosterols per day have LDL-C lowering efficacy ranges of 8–10%. Some observational studies also showed an inverse association between phytosterols and LDL-C reduction. Beyond the cholesterol-lowering beneficial effects of phytosterols, the association of phytosterols with CVD risk events such as coronary artery disease and premature atherosclerosis in sitosterolemia patients have also been reported. Furthermore, there is an increasing demand to determine the association of circulating phytosterols with vascular health biomarkers such as arterial stiffness biomarkers. Therefore, this review aims to examine the ability of phytosterols for CVD risk prevention by reviewing the current data that looks at the association between dietary phytosterols intake and serum lipid biomarkers, and the impact of circulating phytosterols level on vascular health biomarkers. The clinical studies in which the impact of phytosterols on vascular function is investigated show minor but beneficial phytosterols effects over vascular health. The aforementioned vascular health biomarkers are pulse wave velocity, augmentation index, and arterial blood pressure. The current review will serve to begin to address the research gap that exists between the association of dietary phytosterols with CVD risk biomarkers.  相似文献   

16.
Inhibition of pyrazine formation by natural antioxidants and the foods containing them was measured in a microwaved glucose/glycine model system. Inhibition of lipid oxidation by the same materials was assayed in both bulk and emulsion systems. Pyrazines were determined by solid-phase micro extraction followed by GC. Lipid oxidation volatiles were assayed by polyamide fluorescence produced by either a bulk oil display or a hematin- or 2,2′-azobis-(2-amidino=propane) dihydrochloride-accelerated lecithin or fish oil emulsion. It was shown that (i) the inhibition of pyrazine formation depends on high concentrations of water-soluble antioxidants; (ii) such antioxidants occur naturally in some foods and are usually polyphenols; (iii) during pyrazine inhibition, oxidized polyphenols show enhanced nonfluorescing browning similar to enzymic browning products; (iv) monophenols, which structurally cannot form quinone polymers on oxidation, inhibit pyrazines with less browning; (v) during the final pyrazine-forming phase of the Maillard reaction, polyphenolics and reducing agents such as glutathione and ascorbic acid are partially consumed with some nutritional loss; (vi) fruit powders of grape seed, grape skin, and red wine are highly pyrazine-inhibitory, steeped blueberry strongly so, but plum purees are moderately pro-pyrazine, and freeze-dried vegetables strongly pro-pyrazine; and (vii) black and green tea infusions are highly inhibitory, whereas spices have mixed effects.  相似文献   

17.
The American Dietetic Association (ADA) has stated that the best nutritional strategy for promoting optimal health and reducing the risk of chronic disease is to wisely choose a wide variety of foods. Seventy diets were computer analyzed from the menu of athletes or sedentary subjects seeking to improve the quality of micronutrient intake from food choices. All of these dietary analyses fell short of the recommended 100% RDA micronutrient level from food alone. Therefore, based on diets analyzed for adequacy or inadequacy of macronutrients and micronutrients, a challenging question is proposed: "Does food selection alone provide 100% of the former RDA or newer RDI micronutrient recommended daily requirement?"  相似文献   

18.
An international, multilaboratory collaborative study was carried out to evaluate the performance of Official Method Ce 12‐16 of the American Oil Chemists’ Society (AOCS) for the determination of plant sterols and stanols, collectively referred to as phytosterols, in foods and dietary supplements containing added phytosterols and in the phytosterol food additive concentrates used to prepare such products. AOCS Official Method Ce 12‐16 involves the extraction of free sterols/stanols and saponified steryl/stanol esters followed by the gas chromatographic separation and flame ionization detection of phytosterol trimethylsilyl ether derivatives. A total of 14 laboratories from six countries successfully completed the analysis of collaborative samples of foods (e.g., baked goods, beverages, margarines; n = 9), dietary supplements (n = 5), and phytosterol concentrates (n = 4). Study results for the contents of total phytosterols (weight/weight) were 0.19–8.4% for foods, 8.7–49% for dietary supplements, and 57–97% for concentrates. AOCS Official Method Ce 12‐16 showed acceptable performance for total and individual phytosterols, indicating that this method was suitable for the determination of added phytosterols in a wide variety of market products and concentrates. AOCS Official Method Ce 12‐16 is appropriate for the determination of the five major phytosterols (i.e., campesterol, stigmasterol, β‐sitosterol, campestanol, and sitostanol) that are the subject of the United States Food and Drug Administration's health claim for phytosterols and the reduced risk of coronary heart disease.  相似文献   

19.
Arne Nordøy 《Lipids》1999,34(1):S19-S22
The effects of dietary fats have been established in epidemiological and intervention studies and through relationship to risk factors for development of coronary heart disease (CHD). During a period where the impressive effects of hydroxymethylglutaryl-CoA reductase inhibitors on the mortality of CHD dominate the medical journals, it is important to realize the major effects of dietary fatty acids on a series of events included in the multifactorial disorder of CHD.  相似文献   

20.
Fatty acids (FAs) are essential components of cell membranes and play an integral role in membrane fluidity. The lipophilic index [LI, defined as the sum of the products between FA levels and melting points (°C), divided by the total amount of FA: \({\text{LI}} = \frac{{\mathop \sum \nolimits_{k} [{\text{fatty acid}} \times {\text{melting point}}]}}{{\mathop \sum \nolimits_{k} {\text{fatty acid}} }}\)] is thought to reflect membrane and lipoprotein fluidity and may be associated with the risk of coronary heart disease (CHD). Therefore, we examined the associations of dietary and plasma phospholipid (PL) LI with CHD risk among postmenopausal women. We determined dietary LI for the cohort with completed baseline food frequency questionnaires and free of prevalent cardiovascular diseases in the Women’s Health Initiative (WHI) observational study (N = 85,563). We additionally determined plasma PL LI in a matched case-control study (N = 2428) nested within the WHI observational cohort study. Cox proportional hazard regression and multivariable conditional logistic regression were used to calculate HRs/ORs for CHD risk between quartiles of LI after adjusting for potential sources of confounding and selection bias. Higher dietary LI in the cohort study and plasma PL LI in the case-control study were significantly associated with increased risk of CHD: HR = 1.18 (95% CI 1.07–1.31, P for trend <0.01) and OR = 1.76 (95% CI 1.33–2.33, P for trend <0.01) comparing extreme quartiles and adjusting for potential confounders. These associations still persisted after adjusting for the polyunsaturated to saturated fat ratio. Our study indicated that higher LI based on either dietary or plasma measurements, representing higher FA lipophilicity, was associated with elevated risk of CHD among postmenopausal women.  相似文献   

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