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

Folic acid deficiency represents a vitamin deficiency that may be due either to an inadequacy of the dietary supply or to an increased requirement. It leads to a number of abnormalities including hematological, neurological and cardiovascular disorders. In this study, we investigated whether folic acid deficiency would influence platelet and macrophage activities. For 6 weeks, rats were fed a test diet containing a low amount of folic acid (250 mu g/kg) by comparison with a control diet (750 mu g/kg). We found 40 and 32 percent reductions (P < 0.05) of plasma and erythrocyte folates, respectively in the tested group. Peritoneal macrophages of the folic acid deficient animals exhibited greater (20 x) tissue factor (TF) activity than in the controls. We also found that folate depletion significantly enhanced the thrombin- and ADP-induced platelet aggregation (+64 and + 13 percent, respectively). Moreover, the results of incubations with radiolabeled arachidonic acid indicated that platelets of folic acid deficient animals incorporated more labeling than controls did. When stimulated with thrombin, the mobilization of arachidonate from platelet phospholipids and its subsequent formation of cyclooxygenase and lipoxygenase metabolites were enhanced in the deficient animals. In particular, thromboxane biosynthesis was markedly increased. The analysis of the plasma fatty acid composition showed a decrease in the plasma unsaturation index related to a marked fall of long chain (n-3) fatty acids which was also observed in platelets. These data suggested the occurrence of an oxidative stress in folic acid deficient animals which was confirmed by increases in plasma lipid peroxidation products (more than +20 percent) and an enhanced susceptibility of erythrocytes to free radicals (+23 percent). Altogether these data suggested that folic acid deficiency altered the circulating and cellular fatty acid composition and thus influenced the balance of the platelet eicosanoid synthesis. In addition, total homocysteine and glutathione concentrations were highly increased in plasma from folate-depleted rats. From these results, we conclude that folate deficiency can potentiate the coagulation pathway mediated by the macrophage TF as well as the platelet activation process. It is suggested that these dysfunctions might be related to the loss of (n-3) polyunsaturated fatty acids. The latter could result from an increased lipid peroxidation triggered by the folic acid deficiency-induced hyperhomocysteinemia.
Atherosclerosis 1996 Apr 05
PMID:Pro-thrombotic effects of a folic acid deficient diet in rat platelets and macrophages related to elevated homocysteine and decreased n-3 polyunsaturated fatty acids. 912 97

Fish oil is rich in the long chain omega-3 (omega-3) polyinsaturated fatty acids (PUFA), Pioneering studies of Dyerberg and Bang primarily originate interests in this way. The low incidence of acute myocardial infarction they verified within the Greenland Eskimos suggested that a high dietary omega-3 PUFA intake due to marine food might protect against coronary heart disease. They showed that the Eskimos had a beneficial lipid pattern and that their balance between pro-aggregatory thromboxanes and anti-aggregatory prostacyclins was shifted towards an anti-thrombotic state. The two major omega-3 fatty acids are decosapentaenoic acid (EPA C 20:5, omega 3), with five double bonds, and docosahexaenoic acid (DHA C 22:6, omega 3), with six double bonds. These fatty acids' significant effects include reduction of plasma triglycerides and lipoprotein levels as well as of platelets thrombogenicity in the microcirculation, which is due to effects on the mediators production derived from arachidonic acid (prostaglandins and leucotrienes), meddling in inflammatory and immune cell function, retarded atherosclerosis development. Experimental studies of atherogenesis and arterial thrombogenesis support the hypothesis that dietary omega-3 PUFA intake may play a leading role in primary or secondary prevention of coronary heart disease.
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PMID:[Cardiovascular disease and omega-3 fatty acids]. 941 11

Interest in effects of diet on postprandial lipoproteins has increased in recent years as a result of accumulating evidence for adverse cardiovascular consequences of elevated concentrations of triglyceride rich lipoproteins. Particular attention has been given to ability of different fatty acids to modulate postprandial lipoprotein responses because of evidence for both harmful and protective cardiovascular properties of the saturated, monounsaturated and omega-6 and omega-3 polyunsaturated fatty acid (PUFA) classes. Evidence for direct atherogenic properties of chylomicron remnants has led to attempts to monitor effects of diet specifically on this lipoprotein class. Limitations in the methods employed to measure chylomicron remnants and the small number of human studies which have evaluated effects of meal, and background diet, fatty acid composition, makes it difficult to draw definitive conclusions at the present time. However consideration of data from both animal and human studies tends to support the conclusion that diets, and meals, rich in PUFA (particularly long chain omega-3 PUFA), result in attenuated postprandial responses of the intestinally-derived lipoproteins. Attenuated responses to high PUFA meals appear to be due to greater rates of clearance and greater activation of lipoprotein lipase (LPL). Attenuated responses to high PUFA background diets may be due to adaptive changes involving both accelerated rates of clearance in peripheral tissues and liver, as well as decreased output of the competitor for chylomicron clearance, very low density lipoprotein (VLDL).
Atherosclerosis 1998 Dec
PMID:Dietary interventions affecting chylomicron and chylomicron remnant clearance. 988 49

Lipid disorders and cardiovascular diseases have been related in many studies. We here studied the influence of acute ingestion of a long chain triglyceride (LCT) emulsion (rich in triglycerides) on plasma triglyceride (TG) and total cholesterol (TC) levels in laboratory animals (Wistar rats), comparing it with the induction of hypertriglyceridaemia and hypercholesterolaemia by Triton WR-1339 injection. The results show that Triton would be suitable for inducing hypercholesterolaemia but not hypertriglyceridaemias similar to those in humans. The LCT emulsion intake, however, provoked transitory hyperlipaemia with values similar to those often found in hyperlipaemic subjects, and would thus be suitable for testing possible antilipaemic treatments. Our study also presents a model of hypertriglyceridaemia, hypercholesterolaemia and obesity in experimental animals, provoked by a chronic intake of an LCT emulsion. This model may be useful in investigating the mechanisms of the pathogenesis of atherosclerosis and the pharmacological treatment of obesity and dyslipaemias.
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PMID:Experimental hypertriglyceridaemia and hypercholesterolaemia in rats. 1075 70

Statins and polyunsaturated fatty acids have similar actions: both enhance endothelial nitric oxide synthesis, inhibit the production of pro-inflammatory cytokines, lower cholesterol levels, prevent atherosclerosis and are of benefit in coronary heart disease, stroke and osteoporosis. Statins enhance the conversion of linoleic acid and eicosapentaenoic acid to their long chain derivatives. Animals with essential fatty acid deficiency show an increase in HMG-CoA reductase activity, which reverts to normalcy following topical application of linoleic acid. Similarly to statins, polyunsaturated fatty acids also inhibit HMG-CoA reductase activity. In view of the similarity in their actions and as statins influence essential fatty acid metabolism, it is suggested that essential fatty acids and their metabolites may serve as second messengers of the actions of statins.
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PMID:Essential fatty acids as possible mediators of the actions of statins. 1148 6

Largely initiated by studies among Greenland Eskimos in the early 1970s, great attention has been given to the possible effects of the very long chain n-3 polyunsaturated fatty acids (PUFA) in a variety of cardiovascular disease states. A series of possibly positive effects on pathogenetic mechanisms in cardiovascular disease has evolved from laboratory studies in cell cultures and animals as well as in humans, focusing mainly on eicosanoid metabolism with reduced activities of platelets and leucocytes, reduced plasma triglycerides and, antiarrhythmic effects in the myocardium. A rationale for a positive effect of very long chain n-3 PUFA in the secondary prophylaxis after revascularization procedures obviously also exists. The positive clinical effects based on prospectively randomized trials are summarized as follows. After coronary artery bypass grafting (CABG), the SHOT study showed statistically significant reduction in angiographic vein graft occlusion in 610 patients after 1 yr with supplementation of 3.4 g/d of highly concentrated very long chain n-3 PUFA. The reduction in occlusion rates was significantly related to the change in the n-3 PUFA concentration in serum phospholipids during the study period with the occlusion rate in the upper quartile of such changes at only approximately 50% of that in the lower quartile. These results were also clearly related to the presence of angina pectoris and occurrence of myocardial infarction after 1 yr. Several studies were conducted in patients after percutaneous transluminal coronary angioplasty (PTCA). By 1993, two meta-analyses indicated a positive effect on the restenosis rate, a significant problem after otherwise successful PTCA. During the late 1990s, three large prospective randomized placebo-controlled angiographic studies were conducted with very long n-3 PUFA 5.1-8.0 g/d, all with completely negative results. Today, therefore, very long chain n-3 PUFA supplementation cannot be recommended to reduce the incidence of restenosis after PTCA. All studies were performed without stenting of the coronary lesion. In the very special revascularization procedure of heart transplantation, evolving hypertension and accelerated atherosclerosis have been major clinical problems. In other studies, positive effects by supplementation with very long chain n-3 PUFA (3.4-5.7 g/d) were obtained on the surrogate end points coronary vasoreactivity to acetylcholine and hypertension, respectively. On the basis of the presently available literature from clinical studies, recommendations for supplementation with very long chain n-3 PUFA can be given to patients after venous CABG (up to 3.4 g/d), and after heart transplantation (3.4-5.7 g/d) but not to patients after traditional PTCA. In fact, data from substudies suggested the possibility that large doses (5.1 g/d) of very long chain n-3 PUFA might be contraindicated because they induce a proinflammatory state in patients under oxidative stress.
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PMID:n-3 fatty acids and revascularization procedures. 1183 81

Diagnosis depends on the clinical manifestations, blood or cerebrospinal fluid study and MRI findings. Acute and subacute intraparenchymal spinal cord disorders are due to vascular disorders or myelitis. Spinal cord infarction is associated with dissecting aortic aneurysm, surgical clipping of aortic aneurysms, aortic atherosclerosis or hypotension from any cause. Hematomyelia results from trauma, vascular malformations, vasculitis, or a coagulation disorder. Acute infectious myelopathies result from direct invasion of the spinal cord by bacteria, parasite, or virus. The cause of acute or subacute inflammatory disease include multiple sclerosis, Devic disease, acute disseminated encephalomyelitis, SLE, or sarciodosis. Sarcoidosis sometimes requires differential diagnosis with cord tumor. Chronic intraparenchymal spinal cord disorders are due to syringomyelia, familial spastic paraplegia, HTLV-1 associated myelopathy, adrenomyeloneuropathy, and vascular malformations. HTLV-1 associated myelopathy present with progressive spastic paraplegia with bladder disturbance and has antibodies to HTLV-1 in the cerebrospinal fluid and serum. Diagnosis of adrenomyeloneuropathy is made by demonstration of elevated levels of very long chain fatty acids in plasma. Vascular malformations are important lesions because they present a treatable cause of progressive myelopathy.
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PMID:[Medical approach to intraparenchymal spinal cord disorders]. 1278 77

The proteoglycan versican is one of several extracellular matrix (ECM) molecules that accumulate in lesions of atherosclerosis and restenosis. Its unique structural features create a highly interactive molecule that binds growth factors, enzymes, lipoproteins, and a variety of other ECM components to influence fundamental events involved in vascular disease. Versican is one of the principal genes that is upregulated after vascular injury and is a prominent component in stented and nonstented restenotic lesions. The synthesis of versican is highly regulated by specific growth factors and cytokines and the principal source of versican is the smooth muscle cell. Versican interacts with hyaluronan, a long chain glycosaminoglycan, to create expanded viscoelastic pericellular matrices that are required for arterial smooth muscle cell (ASMC) proliferation and migration. Versican is also prominent in advanced lesions of atherosclerosis, at the borders of lipid-filled necrotic cores as well as at the plaque-thrombus interface, suggesting roles in lipid accumulation, inflammation, and thrombosis. Versican influences the assembly of ECM and controls elastic fiber fibrillogenesis, which is of fundamental importance in ECM remodeling during vascular disease. Collectively, these studies highlight the critical importance of this specific ECM component in atherosclerosis and restenosis.
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PMID:Proteoglycans in atherosclerosis and restenosis: key roles for versican. 1514 69

The aim of the present study was to investigate the effect of long-term diet and very long chain n-3 fatty acids (VLC n-3) intervention on plasma coagulation factor VII (FVII), choline-containing phospholipids (PC) and triglycerides (TG), especially related to the R353Q polymorphism of the FVII gene. The present investigation included 219 subjects from the Diet and Omega-3 Intervention Trial on atherosclerosis (DOIT), a 2x2 factorial designed study in elderly men with long-standing hypercholesterolemia. The subjects were randomly allocated to receive placebo capsules (corn oil) (control), placebo capsules and dietary advice ("Mediterranean type" diet), VLC n-3 capsules, or VLC n-3 capsules and dietary advice combined. The R353Q genotype and the levels of FVIIc, FVIIag, FVIIa, PC, and TG at baseline and after 6 months were determined. Diet intervention was followed by a significant reduction of 5.1% in the levels of FVIIag and 2.4 mU/ml in FVIIa (95% CI -7.4, -2.9, and -3.8, -1.1, respectively) (both p<0.001) compared to the no diet group, independent of genotype. No effects of diet intervention on FVIIc, PC or TG were observed. After VLC n-3 supplementation the TG levels were significantly reduced compared to placebo (p=0.01), whereas all FVII levels and PC remained unchanged. Dietary advice towards a "Mediterranean type" diet, but not VLC n-3 supplementation, was shown to reduce the levels of FVIIag and FVIIa after 6 months, independent of genotype. The results indicate the dietary advice to be more favourable in reducing this risk factor for CVD as compared to specific VLC n-3 supplementation.
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PMID:The effects of long-term diet and omega-3 fatty acid supplementation on coagulation factor VII and serum phospholipids with special emphasis on the R353Q polymorphism of the FVII gene. 1517 95

Epidemiological studies have shown an inverse relationship between intake of N-3 fatty acids and incidence of stroke. And, there is a high incidence of stroke in patients with carotid atherosclerosis. We investigated the relationship between intake of N-3 fatty acids and carotid atherosclerosis in the cross-sectional study. A total of 1920 Japanese, aged over 40 years, received a population-based health examination in 1999. They underwent B-mode carotid ultrasonography to evaluate the carotid intimal-medial thickness (IMT). Eating patterns were evaluated by a 105 items food frequency questionnaire. A complete data set was available for 1902 subjects (785 men and 1117 women). The mean eicosapentaenoic acid (EPA) intake in men was 0.32+/-0.23 g/day and in women was 0.31+/-0.20 g/day. The mean docosahexaenoic acid (DHA) intake in men was 0.52+/-0.34 g/day and in women was 0.49+/-0.29 g/day. With multiple linear regression analysis, after adjustments for age, sex, and total energy intake, intakes of EPA (P < 0.05), DHA (P < 0.05), and docosapentaenoic acid (P < 0.05) were significantly and inversely related to IMT. These data indicate that dietary N-3 fatty acid, especially very long chain N-3 fatty acids, may protect against carotid atherosclerosis.
Atherosclerosis 2004 Sep
PMID:Very long chain N-3 fatty acids intake and carotid atherosclerosis: an epidemiological study evaluated by ultrasonography. 1530 87


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