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)

Recent epidemiological studies have shown some beneficial health effects of the long chain (n-3) polyunsaturated fatty acids found in fatty fish. Although the results of these studies are often ambiguous and inconclusive, they have prompted many intervention trials to study the effects of n-3 fatty acids (FA) on the cardiovascular risk profile. However screening of the literature revealed that many of the beneficial effects of fish (oil) were obtained in intervention studies which had several serious shortcomings in their design. Therefore we started a placebo controlled randomised trial with increasing doses of n-3FA (respectively 0; 1.12; 2.24 and 3.37 g n-3 FA/day) and in order to have a maximum compliance this study was done in healthy monks. Fifty eight subjects took the fish oil capsules during 12 months and were thereafter followed for another 6 months. We couldn't detect any effect of n-3 FA supplementation on total cholesterol, HDL cholesterol, LDL cholesterol, apo A1, Lp(a), HbA1C, glucose, fibrinogen, factor VIII, antithrombin III, plasminogen activator inhibitor, tissue plasminogen activator and von Willebrand factor concentration, on bleeding time or on systolic or diastolic blood pressure. A pronounced significant dose dependent decrease of triglyceride levels was seen, while a slight but statistical significant decrease of apo B levels was observed in the highest fish oil dose. As the importance of triglycerides in the pathogenesis of atherosclerosis is still under discussion, the clinical relevance of these finding is not clear at the moment. It seems therefore improbable that the anti-atherosclerotic action of n-3 FA is due to an effect on the lipid, apoprotein, coagulation or fibrinolysis parameters as measured in our study. Hence further research must be focused on other parameters (prostaglandins) which can be influenced by n-3 FA and which probably play an equally important role in the atherosclerotic process.
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PMID:Influence of supplementation with N-3 fatty acids on different coronary risk factors in men--a placebo controlled study. 141 84

Hemostatic variables are increasingly recognized as atherothrombotic risk markers and their susceptibility to lifestyle changes has therefore considerable interest. To study this subject knowledge of the spontaneous variability of measures of coagulation and fibrinolysis is required. We monitored 17 young male adults with constant lifestyles for a year and here present characteristics of the observed variability of factor VII coagulant activity (F VIIc), fibrinogen, fibrinolytic variables and blood lipids. The variables differed considerably with regard to total variability (range of CV (%): 13-54) and with respect to relative size of the inter- and intrapersonal components of variation. None of the variables showed seasonal changes of biological significance. Descriptive statistics of the same variables measured in 74 young healthy adults (19 women, 55 men) are also reported. These values may be used as a reference for comparable groups of individuals. Serum triglycerides were significantly associated with F VIIc (Spearman's Rs = 0.24, P < 0.05) and plasma concentrations fo the plasminogen activator inhibitor type I (Spearman's RS = 0.23, P = 0.05). An increased thrombotic tendency with elevated triglyceride levels was thus indicated. Serum cholesterol was not associated with hemostatic variables, except for plasminogen activator activity (Spearman's Rs = 0.31, P < 0.05).
Atherosclerosis 1992 Oct
PMID:The variability of and associations between measures of blood coagulation, fibrinolysis and blood lipids. 146 54

To assess the relationship between the fibrinolytic system and coronary risk factors, several fibrinolytic parameters were measured in 72 male survivors of myocardial infarction and in 53 age-matched healthy controls. The coronary patients had significantly higher plasminogen activator inhibitor (PAI) activity than the control subjects, while t-PA antigen did not differ between the groups. After stratifying the coronary patients in 14 diabetic and 58 nondiabetic patients, the elevated PAI activity remained limited to the diabetic group. PAI activity correlated significantly with systolic blood pressure, blood glucose, body mass index and LDL cholesterol. In multivariate regression analysis, significant associations persisted between PAI and diabetes, body mass index and LDL cholesterol. Coronary disease had no impact on the regression model. Our results suggest that the increased PAI-1 in selected groups of coronary patients is not a consequence of coronary disease itself, but is rather related to the metabolic risk factors of atherosclerosis, especially diabetes.
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PMID:Increased plasminogen activator inhibitor activity in survivors of myocardial infarction is associated with metabolic risk factors of atherosclerosis. 146 21

Decreased fibrinolytic capacity has been suggested to accelerate the process of arterial atherogenesis by facilitating thrombosis and fibrin deposition within developing atherosclerotic lesions. Type 1 plasminogen activator inhibitor (PAI-1) is the primary inhibitor of tissue-type plasminogen activator and has been found to be increased in a number of clinical conditions generally defined as prothrombotic. To investigate the potential role of this inhibitor in atherosclerosis, we examined the expression of PAI-1 mRNA in segments of 11 severely diseased and 5 relatively normal human arteries obtained from 16 different patients undergoing reconstructive surgery for aortic occlusive or aneurysmal disease. Densitometric scanning of RNA (Northern) blot autoradiograms revealed significantly increased levels of PAI-1 mRNA in severely atherosclerotic vessels (mean densitometric value, 1.7 +/- 0.28 SEM) compared with normal or mildly affected arteries (mean densitometric value, 0.63 +/- 0.09 SEM; P less than 0.05). In most instances, the level of PAI-1 mRNA was correlated with the degree of atherosclerosis. Analysis of adjacent tissue sections from the same patients by in situ hybridization demonstrated an abundance of PAI-1 mRNA-positive cells within the thickened intima of atherosclerotic arteries, mainly around the base of the plaque. PAI-1 mRNA could also be detected in cells scattered within the necrotic material and in endothelial cells of adventitial vessels. In contrast to these results, PAI-1 mRNA was visualized primarily within luminal endothelial cells of normal-appearing aortic tissue. Our data provide initial evidence for the increased expression of PAI-1 mRNA in severely atherosclerotic human arteries and suggest a role for PAI-1 in the progression of human atherosclerotic disease.
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PMID:Increased type 1 plasminogen activator inhibitor gene expression in atherosclerotic human arteries. 149 92

In patients with non-insulin-dependent diabetes mellitus, concentrations in plasma of insulin and its precursors, proinsulin and split proinsulin, are increased. Because increased concentrations of plasminogen activator inhibitor type-1 (PAI-1) occur also, we hypothesized that proinsulin and split proinsulin may augment endothelial cell PAI-1 expression, thereby potentially attenuating endogenous fibrinolysis and accelerating atherosclerosis. Proinsulin increased PAI-1 activity in conditioned media of endothelial cells as did split proinsulin, paralleled by increased expression of PAI-1 mRNA. These effects of proinsulin were not dependent on its conversion to insulin nor on its interactions with the insulin receptor. The proinsulin stimulation of PAI-1 expression was not attenuated by either anti-insulin receptor antibodies or a 100-fold excess of insulin. Furthermore, proinsulin-mediated increases in PAI-1 expression were not inhibited by a 500-fold excess of insulinlike growth factor I. In addition, inhibition of tyrosine kinase, which mediates many of the diverse effects of insulin and insulinlike growth factor I, did not attenuate the effect of proinsulin. These results indicate that proinsulin augments PAI-1 expression, potentially contributing to vasculopathy in patients with non-insulin-dependent diabetes mellitus.
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PMID:Stimulation by proinsulin of expression of plasminogen activator inhibitor type-I in endothelial cells. 161 5

Accelerated atherosclerosis accompanying diabetes mellitus, obesity, and some types of hypertension has been associated with hyperinsulinemia, augmented plasma plasminogen activator inhibitor type 1 (PAI-1), or both. We hypothesized that insulin and insulin-like growth factor type I (IGF-I) can influence synthesis of PAI-1, thereby potentially attenuating fibrinolysis. In HepG2 cells used as a model system, concentrations of insulin and IGF-I consistent with those seen in plasma independently stimulated PAI-1 synthesis. Accumulation of PAI-1 protein in conditioned medium over 24 hr was stimulated more with insulin alone than with the combination. Synergistic increases were evident, however, in the accumulation of PAI-1 protein over 48 hr with a concomitant increase in PAI-1 mRNA. A 10- to 20-fold increase in IGF binding protein I mRNA was seen 16-48 hr after exposure of the HepG2 cells to insulin and IGF-I, an increase abolished by cycloheximide. The results obtained are consistent with the hypothesis that hyperinsulinemia coupled with physiologic concentrations of IGF-I may attenuate fibrinolytic activity in vivo, thereby contributing to accelerated atherosclerosis.
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PMID:Augmentation of synthesis of plasminogen activator inhibitor type 1 by insulin and insulin-like growth factor type I: implications for vascular disease in hyperinsulinemic states. 171 59

To explore the relationship between impaired fibrinolysis and myocardial infarction, we conducted a literature search and reviewed the published data. The results indicate that myocardial infarction has a significant influence on fibrinolytic activity and that impaired fibrinolysis is more frequent in patients who have had a myocardial infarction than in healthy control subjects. Prospective cohort studies indicate that tests for global fibrinolytic activity are not of prognostic value for first or recurrent myocardial infarction. However, high levels of plasminogen activator inhibitor and low levels of tissue plasminogen activator activity were associated with an increased risk of reinfarction in survivors of a first myocardial infarction. Whether this relationship between impaired fibrinolysis and reinfarction is causal or coincidental is unclear. There is evidence that impairment of fibrinolytic activity is more marked in patients with myocardial infarction who have minimal coronary atherosclerosis than in those who have marked atherosclerosis, suggesting that impaired fibrinolytic activity might be of pathogenetic importance in this small subgroup of patients.
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PMID:A critical review of the relationship between impaired fibrinolysis and myocardial infarction. 185 39

Epidemiologic studies have shown that insulin is a risk factor for coronary heart disease (CHD). Clinical studies have also demonstrated positive correlations between insulin and blood pressure, triglycerides, total cholesterol, fibrinogen, and plasminogen activator inhibitor. Moreover, there is an inverse correlation between insulin and high-density lipoprotein (HDL). These studies have provided evidence in support of the biologic plausibility of epidemiologic observations, but they have not clearly established insulin's role in the pathogenesis of human cardiovascular diseases (CVD) such as hypertension. In fact, there is considerable evidence that insulin resistance (abnormal nonoxidative glucose disposal), not hyperinsulinemia, is the primary insulin-related abnormality in human hypertension, and that hyperinsulinemia occurs as a response to insulin resistance. Skeletal muscle appears to be the primary site of insulin resistance in essential hypertension, although other organs, such as the kidneys and liver--key sites for cell and water homeostasis and lipoprotein regulation, respectively--may respond normally to insulin. Adipocytes also appear to be a site of insulin resistance. Thus, the putative interrelationship between hyperinsulinemia and insulin resistance, on the one hand, and with blood pressure and lipoproteins, on the other, is a complex one and may involve organ-specific insulin resistance. Altered cation transport is one of several mechanisms by which insulin resistance might raise blood pressure. The Na+, K(+)-ATPase and Ca(2+)-ATPase pumps are insulin sensitive. Thus, when insulin resistance is present, the activity of these pumps in the smooth muscle of the arterial wall might be reduced. This would lead to an intracellular accumulation of sodium and calcium, thereby sensitizing the vascular wall to pressor substances. Moreover, secondary hyperinsulinemia will occur, and insulin has been shown to stimulate sympathetic nervous system activity and to increase renal tubular absorption of sodium. Insulin is also a growth factor and therefore might have a trophic effect on the vessel wall, one that could initiate and/or sustain hypertension as well as atherosclerosis. Abnormal lipoprotein metabolism is yet another possible explanation for the accelerated atherosclerosis that has been observed in persons with abnormal carbohydrate tolerance and insulin resistance. Hyperinsulinemia and insulin resistance both play a role in the expression of elevated very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) levels as well as in the depression of HDL levels. Coronary risk reduction has been disappointing when blood pressure has been lowered with treatment regimens based on thiazide diuretics and/or beta blockers. Thiazides and some beta blockers may further impair tissue insulin sensitivity and often cause blood lipoprotein abnormalities.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Epidemiologic and clinical aspects of insulin resistance and hyperinsulinemia. 186 24

Hypertensive cigarette smokers have an especially high risk of coronary heart disease. Doxazosin, which has beneficial effects on haemodynamic factors and lipid metabolism, may be suitable for treating these patients. The haemodynamic and metabolic effects of doxazosin were investigated in a 16-week open, parallel, comparative study of 64 heavy cigarette smokers and 69 non-smokers after a 4-week placebo period. Of the 133 patients who entered, six patients (one smoker and five non-smokers) withdrew due to adverse events. Doxazosin significantly reduced blood pressure without reflex tachycardia in both the smokers and the non-smokers. The therapeutic success rates (reduction in sitting diastolic blood pressure to less than or equal to 90 mmHg and greater than or equal to 5 mmHg reduction, or greater than or equal to 10 mmHg reduction from baseline) were similar for the smokers (93.3%) and the non-smokers (92.5%). Doxazosin significantly decreased total cholesterol and low-density lipoprotein (LDL) cholesterol, but increased high-density lipoprotein (HDL) cholesterol and the HDL:total cholesterol ratio in both smokers and non-smokers. Doxazosin corrected the reduction in HDL cholesterol caused by smoking; compared with baseline, doxazosin increased HDL cholesterol by 19% in hypertensive smokers. The beneficial effects of doxazosin on blood pressure and the lipid profile were apparent in the change in the 10-year probability of developing coronary heart disease as calculated by the Framingham equation; the calculated risk of coronary heart disease decreased by 39% in smokers and by 33% in non-smokers. Plasma fibrinogen and plasminogen activator inhibitor, which independently contribute to atherosclerosis, were significantly reduced by doxazosin in the non-smokers but not in the smokers.
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PMID:Selective alpha 1 inhibition with doxazosin in hypertensive smokers and non-smokers: haemodynamic and metabolic effects. 198 Oct 76

In a double-blind study, a single dose of 1600 mg cyclandelate or placebo was administered to 10 patients with cerebrovascular and/or peripheral vascular disease, and fibrinolytic activity was evaluated before and 1, 2, 4 and 6 h after treatment. Cyclandelate induced a reduction in euglobulin lysis time, an increase in tissue plasminogen activator concentration and a reduction in plasminogen activator inhibitor, alpha 2-antiplasmin and immunological fibrinogen concentrations, but no changes in antithrombin III and plasminogen concentrations were observed. After placebo administration no significant changes were observed. After treating two patients with 800 mg cyclandelate twice daily for 14 days, 1600 mg cyclandelate stimulated fibrinolysis for 8 h. It is concluded that the fibrinolytic activity of cyclandelate has implications for the treatment of cardiovascular complications of atherosclerosis.
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PMID:Fibrinolytic activity of oral cyclandelate in patients with generalized atherosclerotic vasculopathy: a double-blind study. 212 64


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