ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewIsoflavones - plant polyphenols with oestrogenic activity - are becoming widely distributed in foods and sold as nutriceuticals. Their similarity to steroidal oestrogens has stimulated research into potential cardiovascular benefits. The two major areas, those of lipid lowering and of improved vascular function, are reviewed.Recent findingsA major plasma cholesterol lowering effect has not been sustained in recent publications. Relatively minor reductions in LDL-cholesterol or non-HDL-cholesterol have generally been reported, but studies in which no reduction was found have also been reported. Fewer publications have dealt with effects on vasculature, but these have been more consistent. Arterial compliance, a parameter of the elasticity or distensibility of large arteries, is improved by as much as has been reported for estrogens. Vasodilatory effects on the microcirculation with isoflavones or their metabolites may provide opportunities for pharmacological intervention. The metabolism of isoflavones is reviewed briefly in order to highlight its complexity.SummaryAlthough research has failed to demonstrate substantial cholesterol lowering with dietary isoflavones, consumption of legumes is generally to be encouraged as part of the overall strategy for lowering plasma lipids. The favourable effects of ingested or infused isoflavones on several parameters of arterial function suggest an alternative explanation for the apparent low prevalence of coronary disease in populations that eat legumes as a staple food. A better understanding of the pharmacokinetics and bioavailabilty of individual isoflavones is needed if definitive studies are to be designed.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewOf all known dietary factors, long-chain omega-3 fatty acids may be the most protective against death from coronary heart disease. New evidence has confirmed and refined the cardioprotective role of these fatty acids.Recent findingsOmega-3 fatty acid supplementation reduces the risk of sudden cardiac death and death from any cause within 4 months in post-myocardial infarction patients. Evidence continues to accrue for benefits in the primary prevention of coronary heart disease and stroke, and an anti-arrhythmogenic mechanism is emerging as the most likely explanation.SummaryCurrent evidence suggests that individuals with coronary artery disease may reduce their risk of sudden cardiac death by increasing their intake of long-chain omega-3 fatty acids by approximately 1 g per day.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThe metabolic syndrome, a cluster of disorders often including abdominal obesity, is associated with a high risk of cardiovascular disease and premature death. Insulin resistance is a key feature of the metabolic syndrome. Observational studies have indicated that the type of fat in the diet may be related to the development of insulin resistance and the metabolic syndrome, also independent of possible effects on body weight. Dietary surveys are often imprecise. One way to monitor the type of fat in the diet is to record the fatty acid composition in plasma. This review summarizes recent data on the relationships between fatty acid composition in plasma and insulin resistance, diabetes and other disorders related to the metabolic syndrome.Recent findingsInsulin resistance and insulin resistant states are often associated with the fatty acid pattern in plasma, characterized by an increased proportion of palmitic (16:0) and a low proportion of linoleic (18:2 n-6) acids, with a distribution of other fatty acids indicating an increased activity of delta-9 and delta-6 desaturase. This shows that there may be a causal relationship between the type of fat in the diet and insulin action, an assumption supported by recent dietary intervention studies.SummaryIn a public health perspective these results, from both observational and intervention studies, underline the importance of fat quality in the diet for the development of a number of prevalent diseases. Taken together with several earlier studies and recent epidemiological findings, they give strong support to present dietary guidelines.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThere continues to be considerable interest in the concept that antioxidant therapy may reduce cardiovascular risk. Phenols have antioxidant properties and may be important micronutrients. Epidemiological studies have demonstrated a strong link between phenolic intake and reduced cardiovascular risk, but the mechanism of benefit has not been determined.Recent findingsRecent evidence has emerged that a number of phenolic compounds, particularly flavonoids, reverse vascular endothelial dysfunction. The normal endothelium plays a critical role in regulating vascular function, and endothelial dysfunction is associated with increased cardiovascular risk. The present article reviews the links between phenolic intake, endothelial function and cardiovascular risk.SummaryEndothelium-derived nitric oxide bioactivity appears to be increased by supplementation with a number of phenols, and this may explain some of the favourable effects of high phenolic intake seen in epidemiological studies.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewDiacylglycerol is an intermediate product of triacylglycerol hydrolysis and comprises up to 10% of glycerides in plant-derived edible fats and oils. Recent developments in oil chemistry have led to the availability of a novel diacylglycerol oil for clinical studies. Recent research has shown that the oil containing 70% of unusual 1,3- species has metabolic characteristics distinct from those of triacylglycerol of similar fatty acid composition. This review summarizes recent research in humans and experimental animals into the metabolic effects and possible mechanisms of action of this oil.Recent findingsConsumption of the oil affects lipid metabolism including lowering of plasma triacylglcerol, decreases postprandial lipemia and reduces body fat mass, compared with triacylglcerol. As the fatty acids of the two oils are similar, the metabolic differences reside in their structural differences.SummaryIt is still uncertain whether longer term consumption of the diacylglycerol oil will lead to persistent and consistent reductions in plasma triacylglycerol and body fat. However future studies may demonstrate a role in managing aspects of the metabolic syndrome.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewA significant advance in our understanding of the reverse cholesterol transport pathway occurred in 1999 with the identification of defects in the ATP-binding cassette transporter A1 gene as the cause of Tangier disease. Since this discovery, an overwhelming number of experiments have been conducted to further define the function of this gene. Among the concepts emerging from such studies is a possible role for the gene in cholesterol absorption. The present review summarizes the most recent of these studies, as well as the only report to describe the effects of fatty acids on ATP-binding cassette transporter A1 gene activityin vitro.Recent findingsFrom the one study conducted thus far, it appears that unsaturated fatty acids can reduce ATP-binding cassette transporter A1 gene activityin vitroby enhancing its degradation. Among the primary modulators of the gene's transcription is the liver X receptor, with liver X receptor-selective agonists significantly increasing expression of the gene. While some studies indicate that upregulation of the gene inhibits cholesterol absorption, the results of other studies suggest that it facilitates cholesterol absorption and the transfer of cholesterol into the bile. Preliminary evidence from studies with transgenic and knockout mice supports the concept that increasing ATP-binding cassette transporter A1 gene expression may be beneficial in the prevention of diet-induced atherosclerosis.SummaryAlthough there is substantial evidence fromin vitroandin vivostudies to suggest that the ATP-binding cassette transporter A1 gene regulates intestinal cholesterol absorption, perhaps by mediating cholesterol efflux from the basolateral surface of enterocytes, it remains unclear whether or not this gene is the primary ATP-binding cassette transporter involved in the process.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThe purpose is to evaluate recent findings concerning dietary fats and the risk of coronary heart disease. Monounsaturated fatty acids are often regarded as healthy, and many have recommended their consumption instead of saturated fatty acids and polyunsaturated fatty acids. Support for the benefits of monounsaturated fatty acids comes largely from epidemiological data, but they have not been an isolated, single variable in such studies. Beneficial effects on the plasma lipid profile and LDL oxidation rates have also been identified. More recent findings have questioned the impact of suspected beneficial effects on coronary heart disease, indicating that studies with more conclusive endpoints are needed.Recent findingsHuman dietary studies often produce conflicting results regarding the effects of monounsaturated and polyunsaturated fatty acids on the plasma lipid profile. Monounsaturated and polyunsaturated fatty acids both appear to reduce total and LDL-cholesterol compared with saturated fatty acids; however, the effect on HDL is less clear. Lowered HDL levels in response to low-fat or polyunsaturated fatty acid diets and the decreased protection from oxidation of polyunsaturated fatty acid-enriched LDL may not indicate increased coronary heart disease risk. Several lines of evidence also suggest that polyunsaturated fatty acids may protect against atherosclerosis.SummaryRecommendations to substitute monounsaturated fatty acids for polyunsaturated fatty acids or a low-fat carbohydrate diet seem premature without more research into the effects on the development of atherosclerosis. Current opinions favoring monounsaturated fatty acids are based on epidemiological data and risk factor analysis, but are questioned by the demonstrated detrimental effects on atherosclerosis in animal models.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThis review has two major goals. The first goal is to raise some of the methodological problems associated with studying the genetics of complex disorders, specifically cardiovascular diseases. The second is to update the reader with the most recent findings in the area of genotype-phenotype associations as well as the interaction between genetic factors and cardiovascular disease risk markers, with emphasis on those related to lipid metabolism.Recent findingsIn terms of new information, three topics are presented: (1) new findings related to classical candidate genes, such as apolipoprotein E, cholesteryl ester transfer protein and hepatic lipase; (2) recent reports related to new loci that have joined the growing list of cardiovascular disease candidate genes (i.e. ATP-binding cassette transporters A1 and C6, peroxisome proliferator activated receptor α, interleukin-6); and (3) studies showing that multiple genes appear to be at the intersection of several age-related disorders such as cardiovascular disease, neurological disorders and osteoporosis (i.e. apolipoprotein E, vitamin D receptor, matrix Gla protein, peroxisome proliferator activated receptor γ, angiotensin-converting enzyme, estrogen receptor, androgen receptor, methylenetetrahydrofolate reductase).SummaryThe dramatic increase in our ability to carry out genotyping is creating a tremendous wealth of information in terms of associations between genetic markers and biochemical or clinical phenotypes. Increased attention, however, should be placed on study design and replication of findings. This should also be facilitated by the inclusion of multiple markers per loci in order to provide a more precise definition of the alleles associated with the phenotypes of interest. Moreover, given the fact that most of the phenotypes are equally affected by genetic and environmental factors, studies should emphasize the analyses of their interaction.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewInvestigators, especially those from western countries, have commonly assumed that there is either no association or a direct association of protein intake with elevated blood pressure and atherosclerosis. In contrast, recent observational studies and clinical trials have suggested that increased protein intake, particularly protein from plant sources, might actually reduce blood pressure and prevent cardiovascular disease.Recent findingsIn epidemiological studies, an increased intake of protein has been associated with lower blood pressure and an attenuated increase in blood pressure over time. Furthermore, such studies also suggest that the beneficial effects of increased protein intake result from an increased consumption of protein from plant rather than animal sources. In several predominantly small trials, an increased intake of soy protein lowered blood pressure. With respect to clinical outcomes, reports from large cohort studies suggest that increased protein intake is associated with a reduced risk of ischemic heart disease and perhaps intraparenchymal hemorrhage. In other reports, a higher protein intake is one characteristic of a dietary pattern associated with a reduced risk of ischemic heart disease. The mechanisms by which protein could exert its beneficial effects include an increased intake of biologically active amino acids, peptides, or highly correlated nutrients.SummaryRecent evidence suggests that an increased intake of protein, particularly plant protein, may lower blood pressure and reduce the risk of cardiovascular disease. However, the data are not sufficiently compelling to advocate an increased consumption of protein.

ISSN:0957-9672    

出版商:OVID    

年代:2003

数据来源: OVID