Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Elevations of plasma cholesterol and/or triglycerides, and the prevalence of small, dense LDL particles remarkably increase coronary risk in patients with familial combined hyperlipidemia (FCHL). A total of 14 FCHL patients were studied, to investigate the ability of Omacor, a drug containing the n-3 fatty acids eicosapentaenoic and docosahexaenoic acid (EPA and DHA), to favorably correct plasma lipid/lipoprotein levels and LDL particle distribution. The patients received four capsules daily of Omacor (providing 3.4 g EPA+DHA per day) or placebo for 8 weeks in a randomized, double-blind, cross-over study. Omacor significantly lowered plasma triglycerides and VLDL-cholesterol levels, by 27 and 18%, respectively. Total cholesterol did not change but LDL-cholesterol and apolipoprotein B (apoB) concentrations increased by 21 and 6%. As expected, LDL particles were small (diameter=24.9+/-0.3 nm) and apoB-rich (LDL-cholesterol/apoB ratio=1.27+/-0.26) in the selected subjects. After Omacor treatment LDL became enriched in cholesterol (LDL-cholesterol/apoB ratio=1.40+/-0.17), mainly cholesteryl esters, indicating accumulation in plasma of more buoyant and core enriched LDL particles. Indeed, the separation of LDL subclasses by rate zonal ultracentrifugation showed an increase of the plasma concentration of IDL and of the more buoyant, fast floating LDL-1 and LDL-2 subclasses after Omacor, with a parallel decrease in the concentration of the denser, slow floating LDL-3 subclass. However, the average LDL size did not change after Omacor (25.0+/-0.3 nm). The resistance of the small LDL pattern to drug-induced modifications implies that a maximal lipid-lowering effect must be achieved to reduce coronary risk in FCHL patients.
Atherosclerosis 2000 Feb
PMID:Omacor in familial combined hyperlipidemia: effects on lipids and low density lipoprotein subclasses. 1065 75

We investigated the effect of long-term administration of highly purified eicosapentaenoic acid ethyl ester (EPA-E), an n-3 polyunsaturated fatty acid, on the dysfunction of the endothelium and smooth muscle cells in male WBN/Kob rats, a model of spontaneous diabetes mellitus. After oral 8-month treatment with EPA-E, the agent significantly and dose-dependently increased the migration activity of vascular endothelial cells and also decreased 5-bromodeoxyuridine (BrdU) uptake by vascular smooth muscle cells at a dose of 0.1 g/kg or higher. In addition, there were significant correlations between the endothelial cell migration or smooth muscle cell proliferation and the 4-hour fasting glucose level. These findings suggest that EPA-E has a suppressive effect on thrombosis and atherosclerosis.
 ...
PMID:Long-term administration of highly purified eicosapentaenoic acid ethyl ester improves the dysfunction of vascular endothelial and smooth muscle cells in male WBN/Kob rats. 1114 21

Effects of dietary fats include the development of arteriosclerosis in humans and experimental animals, in addition to hypercholesterolemia. None of the preceding studies explicitly compared the effects of individual fatty acids. To address these issues, we chose exogenously hypercholesterolemic (ExHC) rats and apolipoprotein (apo) E deficient mice as a model for atherosclerosis and assessed the individual role of fatty acids in animals' susceptibility to atherosclerosis. The rats fed on the diet containing DHA or EPA, compared with those fed on the safflower oil (SO) diet, lowered serum cholesterol concentration, prevented platelet aggregation and slowed thickening in the ascending aorta. Apo E deficient mice developed hypercholesterolemia and severe lesion area in aortic root and arch, to a similar extent when they received DHA or SO. These results suggest a direct action of polyunsaturated fatty acids in the arterial wall, in addition to their effects on hypocholesterolemic and haemodynamic action.
 ...
PMID:Role of dietary lipids in arteriosclerosis in experimental animals. 1123 89

Atherosclerosis is a major complication of type 2 diabetes. The pathogenesis of this complication is poorly understood, but it clearly involves production in the vascular wall of macrophage (Mo) lipoprotein lipase (LPL). Mo LPL is increased in human diabetes. Peripheral factors dysregulated in diabetes, including glucose and free fatty acids (FAs), may contribute to this alteration. We previously reported that high glucose stimulates LPL production in both J774 murine and human Mo. In the present study, we evaluated the direct effect of FAs on murine Mo LPL expression and examined the involvement of peroxisome proliferator-activated receptors (PPARs) in this effect. J774 Mo were cultured for 24 h with 0.2 mmol/l unsaturated FAs (arachidonic [AA], eicosapentaenoic [EPA], and linoleic acids [LA]) and monounsaturated (oleic acid [OA]) and saturated FAs (palmitic acid [PA] and stearic acid [SA]) bound to 2% bovine serum albumin. At the end of this incubation period, Mo LPL mRNA expression, immunoreactive mass, activity, and synthetic rate were measured. Incubation of J774 cells with LA, PA, and SA significantly increased Mo LPL mRNA expression. In contrast, exposure of these cells to AA and EPA dramatically decreased this parameter. All FAs, with the exception of EPA and OA, increased extra- and intracellular LPL immunoreactive mass and activity. Intracellular LPL mass and activity paralleled extracellular LPL mass and activity in all FA-treated cells. In Mo exposed to AA, LA, and PA, an increase in Mo LPL synthetic rate was observed. To evaluate the role of PPARs in the modulatory effect of FAs on Mo LPL gene expression, DNA binding assays were performed. Results of these experiments demonstrate an enhanced binding of nuclear proteins extracted from all FA-treated Mo to the peroxisome proliferator-response element (PPRE) consensus sequence of the LPL promoter. PA-, SA-, and OA-stimulated binding activity was effectively diminished by immunoprecipitation of the nuclear proteins with anti-PPAR-alpha antibodies. In contrast, anti-PPAR-gamma antibodies only significantly decreased AA-induced binding activity. Overall, these results provide the first evidence for a direct regulatory effect of FAs on Mo LPL and suggest a potential role of PPARs in the regulation of Mo LPL gene expression by FAs.
 ...
PMID:Direct regulatory effect of fatty acids on macrophage lipoprotein lipase: potential role of PPARs. 1124 88

In short-term studies, both in animals and in humans, fish oil seems to exert anti-inflammatory effects. However, these effects may vanish during long-term treatment. There is a possibility that in autoimmune diseases, supplementation of dietary n-3 fatty acids might lead to a decrease in the number of autoreactive T cells via apoptosis, as demonstrated in (NZBXNZW) F1 lupus mice [40]. Thus, the "fade away" effect might be due to regrowth of pathogenic autoreactive cells. In animal models of autoimmune diseases, diets high in n-3 fatty acids from fish oil increase survival and reduce disease severity in spontaneous autoantibody-mediated disease, while n-6 linoleic acid-rich diets appear to increase disease severity. The situation in human disease is probably more complex. Some of the discrepancy between studies can be attributed to methodologic problems. The effect of fish oil is dose, time and disease-dependent. Since the anti-inflammatory effects depend on the balance between n-3 and n-6 fatty acids, the relative proportion of EPA and DHA and possibly co-treatment with dietary vitamin E, the dose/effect ratio may vary between individuals. Furthermore, some animal studies demonstrating efficacy used very high doses that may be incompatible with human consumption. It seems that fish oil is only mildly effective in acute inflammation. In those chronic inflammatory disorders where it was found to be effective, several weeks are necessary to exhibit results. Yet, this mild anti-inflammatory effect, possibly through downregulation of pro-inflammatory cytokine production, leads to striking therapeutic improvement in critically ill patients. Fish oil supplementation seems advantageous especially in acute and chronic disorders where inappropriate activation of the immune system occurs. Fish oil has only a mild effect on active inflammation of diseases such as rheumatoid arthritis, SLE and Crohn's disease, but it could prevent relapse (in some of the studies). In diseases where the inflammation is mild, such as IgA nephropathy, fish oil may slow or even prevent disease progression. The above could explain the observation in some populations of a decreased incidence of inflammatory and autoimmune diseases [3], since the constant consumption of n-3 fatty acids could suppress any autoreactive (or hyper-reactive) T cells. However, if there is already an existing disease, increased consumption might not be beneficial over a long period. Therefore, the use of n-3 fatty acids can be recommended to the general healthy population, not only to prevent atherosclerosis but possibly also to reduce the risk of autoimmunity.
 ...
PMID:n-3 fatty acids and the immune system in autoimmunity. 1180 9

Oxidized LDL (oxLDL) may contribute to the accumulation of apoptotic cells in atherosclerotic plaques. Although it is well established in monophasic chemical systems that the highly unsaturated EPA and DHA will oxidize more readily than FA that contain fewer double bonds, our previous studies showed that enrichment of LDL, which has discrete polar and nonpolar phases, with these FA did not increase oxidation. The objective of this study was to compare the extent of apoptosis induced by EPA/DHA-rich oxLDL to that induced by EPA/DHA-non-rich oxLDL in U937 cells. LDL was obtained from one healthy subject three times before and after supplementation for 5 wk with 15 g/d of fish oil (FO), an amount easily obtainable from a diet that contains fatty fish. After supplementation, an EPA/DHA-rich LDL was obtained. Oxidative susceptibility of LDL, as determined by measuring the formation of conjugated dienes and the accumulation of cholesteryl ester hydroperoxides, was not higher in EPA/DHA-rich LDL. The oxLDL-induced cell apoptosis was detected by the activation of caspase-3, the translocation of PS to the outer surface of the plasma membrane using the Annexin V-fluorescein isothiocyanate binding assay, and the presence of chromatin condensation and nuclear fragmentation using the 4,6-diamidino-2-phenylindole staining assay. All three measures showed that after FO supplementation, EPA/DHA-rich oxLDL-induced cell apoptosis decreased. The decrease was not related to the concentration of lipid hydroperoxides. This study suggests that a possible protective effect of EPA/DHA-rich diets on atherosclerosis may be through lessening cell apoptosis in the arterial wall.
 ...
PMID:Enrichment of LDL with EPA and DHA decreased oxidized LDL-induced apoptosis in U937 cells. 1237 50

The offspring of coronary heart disease (CHD) patients are at particularly high risk for developing CHD. Endothelial dysfunction is present in the majority of CHD and atherosclerosis patients. Fish oil, rich in n-3 fatty acids has been shown to augment endothelium-dependent vasodilatation in human peripheral and coronary arteries. The aims of this study are to investigate presence of endothelial dysfunction determined by the brachial flow-mediated diameter, nitric oxide, plasma lipids and fibrinogen, and the effect of high doses of fish oil on these parameters. Twenty-four healthy offspring of CHD patients (study group) were supplemented with 9 g/day Alsepa fish oil (each gram containing 180 mg EPA and 120 mg DHA), for a period of two weeks. Plasma nitric oxide, urine nitric oxide, fibrinogens and flow-mediated vasodilatation (FMD) were determined prior to fish oil therapy, two weeks into therapy and four weeks after the end of therapy with fish oil. Twelve healthy subjects (control group) with no family history of heart disease were studied as controls (day one only). The offspring had a lower increase in FMD and lower nitric oxide production, compared with the control group. No other parameters varied between the two groups. The administration of fish oil did not result in any changes in the studied parameters. In healthy offspring of CHD patients, early endothelial dysfunction was documented before evidence of atherosclerosis. Ingestion of fish oil over a 13-day period did not improve endothelial dysfunction.
 ...
PMID:Impaired nitric oxide production, brachial artery reactivity and fish oil in offspring of ischaemic heart disease patients. 1456 Jul 90

We investigated the effect of highly purified eicosapentaenoic acid ethyl ester (EPA-E) on blood coagulation abnormalities and dysfunction of vascular endothelial cells in spontaneously diabetic Otsuka Long-Evans Tokushima Fatty rats. The animals were treated with either EPA-E or lard at a daily dose of 0.3 g/kg/day for 52 weeks by gavage, and their coagulation/fibrinolytic parameters, platelet aggregation, and functions of the vascular endothelial cells were examined. EPA-E significantly improved coagulation-related parameters including prothrombin time, activated partial thromboplastin time, fibrinogen level, and activities of factor II, V, VII, VIII, IX, X, XI, and XII, and antithrombin III, and fibrinolysis-related parameters including plasminogen, tissue-type plasminogen activator, alpha(2)-plasmin inhibitor, and plasminogen activator inhibitor. It also suppressed ADP- or collagen-induced platelet aggregation and the cholesterol/phospholipid molar ratio in platelet membranes at a dose of 0.3 g/kg. In addition, it significantly increased the migration activity of vascular endothelial cells, and decreased the binding of vascular endothelial cells to vascular endothelial growth factor. In contrast, lard had no effect on hypercoagulation, hypofibrinolysis, and platelet hyperaggregation but significantly aggravated the dysfunction of vascular endothelial cells. These data demonstrate that EPA-E beneficially altered certain factors known to promote thrombosis and atherosclerosis in this animal model.
 ...
PMID:Long-term administration of highly purified eicosapentaenoic acid ethyl ester improves blood coagulation abnormalities and dysfunction of vascular endothelial cells in Otsuka Long-Evans Tokushima fatty rats. 1461 17

Multiple risk markers for atherosclerosis and cardiovascular disease act in a synergistic way through inflammatory pathways. This article discusses some of the key inflammatory biochemical risk markers for cardiovascular disease; in particular, the role of three basic cell types affected by these risk markers (endothelial cells, smooth muscle cells, and immune cells), the crucial role of inflammatory mediators, nitric oxide balance in cardiovascular pathology, and the use of nutrients to circumvent several of these inflammatory pathways. Most risk markers for cardiovascular disease have a pro-inflammatory component, which stimulates the release of a number of active molecules such as inflammatory mediators, reactive oxygen species, nitric oxide, and peroxynitrite from endothelial, vascular smooth muscle, and immune cells in response to injury. Nitric oxide plays a pivotal role in preventing the progression of atherosclerosis through its ability to induce vasodilation, suppress vascular smooth muscle proliferation, and reduce vascular lesion formation. Nutrients such as arginine, antioxidants (vitamins C and E, lipoic acid, glutathione), and enzyme cofactors (vitamins B2 and B3, folate, and tetrahydrobiopterin) help to elevate nitric oxide levels and may play an important role in the management of cardiovascular disease. Other dietary components such as DHA/EPA from fish oil, tocotrienols, vitamins B6 and B12, and quercetin contribute further to mitigating the inflammatory process.
 ...
PMID:The role of chronic inflammation in cardiovascular disease and its regulation by nutrients. 1500 43

Endothelial lipase (EL), a new member of the lipase gene family, was recently cloned and has been shown to have a significant role in modulating the concentrations of plasma high-density lipoprotein levels (HDL). EL is closely related to lipoprotein and hepatic lipases both in structure and function. It is primarily synthesized by endothelial cells, functions at the cell surface, and shows phospholipase A1 activity. Overexpression of EL decreases HDL cholesterol levels whereas blocking its action increases concentrations of HDL cholesterol. Pro-inflammatory cytokines suppress plasma HDL cholesterol concentrations by enhancing the activity of EL. On the other hand, physical exercise and fish oil (a rich source of eicosapentaenoic acid and docosahexaenoic acid) suppress the activity of EL and this, in turn, enhances the plasma concentrations of HDL cholesterol. Thus, EL plays a critical role in the regulation of plasma HDL cholesterol concentrations and thus modulates the development and progression of atherosclerosis. The expression and actions of EL in specific endothelial cells determines the initiation and progression of atherosclerosis locally explaining the patchy nature of atheroma seen, especially, in coronary arteries. Both HDL cholesterol and EPA and DHA enhance endothelial nitric oxide (eNO) and prostacyclin (PGI2) synthesis, which are known to prevent atherosclerosis. On the other hand, pro-inflammatory cytokines augment free radical generation, which are known to inactivate eNO and PGI2. Thus, interactions between EL, pro- and anti-inflammatory cytokines, polyunsaturated fatty acids, and the ability of endothelial cells to generate NO and PGI2 and neutralize the actions of free radicals may play a critical role in atherosclerosis.
 ...
PMID:Long-chain polyunsaturated fatty acids, endothelial lipase and atherosclerosis. 1566 1


<< Previous 1 2 3 4 5 6 7 8 9 Next >>