摘要:

Homocysteine is an intermediate compound formed during metabolism of methionine. The results of many recent studies have indicated that elevated plasma levels of homocyst(e)ine are associated with increased risk of coronary atherosclerosis, cerebrovascular disease, peripheral vascular disease, and thrombosis. The plasma level of homocyst(e)ine is dependent on genetically regulated levels of essential enzymes and the intake of folic acid, vitamin B6 (pyridoxine), and vitamin B12 (cobalamin). Impaired renal function, increased age, and pharmacologic agents (e.g. nitrous oxide, methotrexate) can contribute to increased levels of homocyst(e)ine. Plausible mechanisms by which homocyst(e)ine might contribute to atherogenesis include promotion of platelet activation and enhanced coagulability, increased smooth muscle cell proliferation, cytotoxicity, induction of endothelial dysfunction, and stimulation of LDL oxidation. Levels of homocysteine can be reduced with pharmacologic doses of folic acid, pyridoxine, vitamin B12, or betaine, but further research is required to determine the efficacy of this intervention in reducing morbidity and mortality associated with atherosclerotic vascular disease.

ISSN:0957-9672    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The effects of diet on lipoproteins have been studied for many decades. Current research is focused on the effects of individual fatty acids, the extent to which diet influences lipoprotein (a) and the degree to which postprandial lipoprotein metabolism can be influenced. Practical implementation of dietary recommendations aimed at reducing lipoprotein-mediated risk of coronary heart disease remains an important issue.

ISSN:0957-9672    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

In many individuals, LDL-cholesterol levels rise following increased consumption of dietary cholesterol or saturated and trans-monounsaturated fatty acids. In others, a reduction of cholesterogenesis fully compensates for these effects. In responding individuals, much of the increase in LDL-cholesterol observed may result directly from an increase in plasma cholesteryl ester transfer protein activity whose effect is not mediated by hepatic LDL receptors.

ISSN:0957-9672    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Recent reports have contributed new information on the influence of the size and spacing of fat-containing meals on processes related to fat digestion and absorption, lymphatic transport, and postprandial responses of plasma lipoproteins. The postabsorptive concentrations of plasma triglycerides and common polymorphisms of apolipoprotein B and apolipoprotein E exert important influences on postprandial lipoprotein responses. Attention to these characteristics of individuals and groups can facilitate interpretation of responses to meals containing different fatty acids and varying amounts of cholesterol. Additional evidence is accumulating that points to disease related abnormalities of postprandial lipoprotein metabolism related to clearance mechanisms for triglyceride-rich lipoproteins and processes related to reverse cholesterol transport.

ISSN:0957-9672    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Studies on experimental animals have generally supported a role for dietary fat in mammary cancer, but epidemiological studies have given conflicting results. The effects of dietary fat in animals may be due to its high energy density or to other specific effects, and may have relevance for human breast cancer.

ISSN:0957-9672    

出版商:OVID    

年代:1997

数据来源: OVID