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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Atherosclerosis and its consequences account for most of the morbidity and mortality in Western countries. It is a disease of the intima and primarily involves four cell types, i.e., endothelial and vascular smooth muscle cells, monocytes and platelets. In recent years, knowledge on the cellular and molecular mechanisms of these cells and their alterations by cardiovascular risk factors and in atherosclerosis has greatly expanded. In particular, it has become clear that endothelial cells play a crucial role in the regulation of platelet function, coagulation, and vascular tone and structure. Interestingly, endothelial dysfunction occurs early, particularly if cardiovascular risk factors such as hyperlipidemia, hypertension and diabetes are present. This could lead to adhesion of circulating platelets and monocytes and increased accumulation of lipids in the intima, as well as increased contraction, migration and proliferation of vascular smooth muscle cells. One of the enzymes with a key role in vascular homeostasis is angiotensin I converting enzyme (ACE). ACE is located on the endothelial cell membrane and is responsible for the conversion of angiotensin I into angiotensin II, as well as for the breakdown of bradykinin. While the antihypertensive effect of ACE inhibitors probably contributes to their antiatherogenic effects, other mechanisms are likely to be of greater importance. These direct antiatherogenic effects attributable to ACE inhibition are related to their vasculoprotective properties, including antiproliferative and antimitogenic activity, effects on endothelial function, protection against plaque rupture, antithrombotic effects, and possible antioxidant properties. There is overwhelming evidence to demonstrate the beneficial effects of long-term ACE inhibitor treatment in heart failure, acutely for suspected myocardial infarction (MI), and following MI in patients with left ventricular dysfunction. Hypercholesterolemia is a health risk, and epidemiological studies have shown a line between total cholesterol levels and the risk of cardiac events. Studies have shown that lowering the levels of total and low-density lipoprotein cholesterol using HMG-CoA reductase inhibitors can result in a decrease in cardiac morbidity and mortality. Angiographic studies of coronary arteries have demonstrated a disparity between the decrease in cardiac events and the extent of regression of coronary artery lesions. Mechanisms other than the regression of coronary stenosis may therefore be important in the beneficial effect of cholesterol lowering. It may be of major importance that lipid-lowering therapy is associated with improved endothelial function and decreased platelet activity. Thus, both ACE inhibitors and HMG-CoA reductase inhibitors have vasculoprotective properties which may explain their beneficial effects on cardiovascular morbidity and mortality.
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PMID:[Pharmacotherapy of arteriosclerosis and its complications. Effect of ACE inhibitors and HMG-CoA-reductase inhibitors]. 919 90

Fibrates and HMG CoA reductase inhibitors are commonly used in the treatment of diabetic dyslipidaemia. However, these two groups of drugs have not been compared in diabetic patients in a randomized controlled trial. Therefore, a multicentre study was performed in 73 subjects with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) and combined hyperlipidaemia (serum cholesterol 6.2-10.0 mmol l(-1), serum triglycerides 2.3-10.0 mmol l(-1)), comparing the efficacy of 400 mg bezafibrate with 10 mg simvastatin in a double-blind fashion. Treatment with bezafibrate during 12 weeks reduced serum triglycerides significantly more than simvastatin (-41% vs -22%, p < 0.001) and increased HDL cholesterol more (bezafibrate: + 17% vs simvastatin: + 9%, p < 0.05). LDL cholesterol levels decreased by 14% (p < 0.001) during simvastatin and increased by 21% (p < 0.01) during bezafibrate. This increase in LDL cholesterol was positively correlated with fasting serum triglycerides (p < 0.001) and was associated with a reduction of the serum apolipoprotein B concentration, suggesting an increase in LDL particle size. Metabolic control of diabetes (fasting glycaemia; HbA1c) and insulin secretion (C-peptide levels) were unaffected by both treatments. The incidence of side-effects during treatment was similar for both drugs. Thus, 400 mg bezafibrate mainly increases HDL cholesterol and lowers serum triglycerides but at the expense of an increase in LDL cholesterol; 10 mg simvastatin lowers LDL cholesterin more effectively but has a smaller effect on HDL cholesterol and triglycerides.
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PMID:Comparison of bezafibrate and simvastatin in the treatment of dyslipidaemia in patients with NIDDM. 922 86

To study exogenous sterol metabolism during the suppression or stimulation of cholesterol biosynthesis induced by treatments for hyperlipidemia, we determined plasma plant sterol concentrations before and after administration of an HMG-CoA reductase inhibitor, pravastatin, and compared these with changes in these plasma sterol levels by the bile-sequestrating resin, cholestyramine. The effects of the drugs were also studied in a sitosterolemic patient who has had increased plasma levels of plant sterols. Plasma cholesterol levels determined by the HPLC method were decreased significantly after administration of pravastatin. Plasma plant sterol (sitosterol and campesterol) as well as cholestanol concentrations were also significantly reduced. Cholestyramine administration decreased plasma levels of cholesterol, but did not change those of plant sterols in the hypercholesterolemic subjects. Pravastatin had little effect in a sitosterolemic patient on plasma levels of sterols, where cholestyramine decreased the plasma levels of both cholesterol and cholestanol. These results indicate that treatment with the HMG-CoA reductase inhibitor decreases plasma plant sterol concentrations, and suggest that the increased plasma plant sterol levels in sitosterolemia might not be due to the decreased cholesterol biosynthesis in vivo.
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PMID:Effects of an HMG-CoA reductase inhibitor, pravastatin, and bile sequestering resin, cholestyramine, on plasma plant sterol levels in hypercholesterolemic subjects. 922 10

Hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors reduces serum cholesterol in patients with high cholesterol blood levels including organ transplant recipients. HMG-CoA reductase inhibitor also inhibits a series of immune responses and thus have the potential of exerting immunosuppressive effect in patients with organ allografts. Experimentally, HMG-CoA reductase inhibitors reduces transplant arteriosclerosis. Whether this is linked to an immunosuppressive effect or not is unknown. There is little evidence that post-transplant hyperlipidemia directly increases the risk of cardiovascular diseases. Lipid lowering with HMG-CoA reductase inhibitor is not indicated for all allograft recipients but should be used if other cardiovascular risk factors are present.
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PMID:HMG-CoA reductase inhibitors in organ transplantation. 923 13

In all patients with coronary heart disease a fasting lipid profile (total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides) should be obtained. Hyperlipidemias can then be classified as hypercholesterolemia (LDL cholesterol elevated), mixed hyperlipidemia (LDL cholesterol elevated, triglycerides elevated) and hypertriglyceridemia (triglycerides elevated). Primary goal of lipid intervention is a LDL cholesterol < 100 mg/dl, secondary goals are HDL cholesterol > 35 mg/dl and triglycerides < 200 mg/dl. These goals can be reached by dietary intervention alone (reduction in fat and modification of fat intake) or in combination with lipid lowering drugs. Monotherapy with HMG-CoA reductase inhibitors or combined therapy with bile acid sequestrants will allow a reduction in LDL cholesterol by more than 50%; in predominant hypertriglyceridemia fibrates or nicotinic acid will lower triglycerides and elevate HDL cholesterol.
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PMID:[Goals and practical implementation of lipid therapy in coronary heart disease]. 930 97

Both glucocorticoids and cyclosporine are used to prevent rejection in organ transplant recipients. However, long-term treatment with these drugs is known to induce hyperlipidemia and premature development of atherosclerosis. In previous studies, we have shown that the immunosuppressive drug cyclosporine inhibits catabolism of low-density lipoproteins (LDL) mainly by reducing the expression of LDL-receptor messenger RNA (mRNA), thus explaining the increased plasma levels of LDL cholesterol observed in patients treated with cyclosporine. In the present study, our objective was to investigate the mechanism by which glucocorticoids increase plasma levels of LDL cholesterol. We studied the catabolism of LDL in the human hepatoma cell line HepG2. Our results show that hydrocortisone at physiologically relevant concentrations inhibits LDL binding, uptake, and degradation in a dose-dependent way. Moreover, hydrocortisone also reduces the expression of LDL-receptor mRNA in a dose-dependent way. Cyclosporine also has an additive inhibitory effect on hydrocortisone in the catabolism of LDL. The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor fluvastatin reverses the inhibitory effect of both hydrocortisone and cyclosporine. We conclude that treatment with hydrocortisone and/or cyclosporine induces increased plasma levels of LDL cholesterol because of reduced hepatic LDL receptor activity. HMG-CoA reductase inhibitors reverse this undesirable effect and thus reduce the risk of the development of atherosclerosis in patients subjected to immunosuppressive treatment.
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PMID:Additive inhibitory effect of hydrocortisone and cyclosporine on low-density lipoprotein receptor activity in cultured HepG2 cells. 932 21

We are attempting to develop a chemically-induced murine model for the study of atherosclerosis. Injection of poloxamer-407 (P-407) into rats and mice causes significant dose-dependent hypercholesterolemia and hypertriglyglyceridemia. The elevated triglycerides (TG) seem to result primarily from the compound's inhibition of lipoprotein lipase. P-407 also indirectly stimulates the activity of the rate limiting enzyme in cholesterol (CHOL) biosynthesis, HMG CoA reductase. In addition, P-407 promotes changes in the concentration of hepatic CHOL content. These date indicate that the hyper CHOL could be the result of increased CHOL synthesis, as well as a clearing of CHOL from the liver. Chronic injection into mice of P-407 for 145 d produced atherogenic lesions in the aortas of C57BL/6 mice. The response was equivalent to that seen in animals eating a high CHOL diet for 145 d. Cholic acid potentiated the P-407-induced atherogenesis. These data suggest that P-407 could be used as an agent for the study of hyperlipidemia-induced atherogenesis.
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PMID:The poloxamer 407-induced hyperlipidemic atherogenic animal model. 937 76

Monumental advances in the field of lipid metabolism and its relationship to atherosclerotic cardiovascular disease have been achieved during the last half century. Epidemiologic studies have defined lipid disorders as highly significant independent risk factors for coronary heart disease, along with diabetes mellitus, hypertension and smoking. Primary and secondary prevention studies including the Coronary Primary Prevention Trial, Helsinki Heart Study, and the Coronary Drug Project have shown that lowering the atherogenic low density lipoproteins (LDL) and very low density lipoproteins (VLDL) whilst raising the high density lipoproteins (HDL) significantly decreases the risk for coronary disease. Striking evidence that aggressive therapy (to sharply lower LDL and raise HDL with newer drugs) prevents progression and induces regression of coronary narrowing has been obtained in numerous recent studies using quantitative coronary arteriography. An interesting and unexpected lesson learned from these arteriographic studies was that a highly significant reduction within months in several studies in coronary events was out of proportion to improvements in luminal narrowing. Recently, three major clinical trials to assess the effects of cholesterol reduction by the newly discovered HMG CoA reductase inhibitors (statins) have been published. Pravastatin significantly reduced coronary events in hypercholesterolemic patients [mean LDL-Chol. = 5.0 mM/L (192 mg/dl)] without a history of myocardial infarction. In a secondary prevention study, simvastatin also reduced coronary complications in hypercholesterolemic patients [mean LDL-Chol. = 4.9 mM/L (190 mg/dl)] with pre-existing coronary disease. Very recently, pravastatin treatment significantly reduced coronary events and stroke in patients with a history of myocardial infarction and average cholesterol levels [mean LDL-Chol. = 3.6 mM/L (139 mg/dl)], representing the majority of patients with coronary disease. In all these studies, reduction in cardiovascular events was approximately one-third. In subgroup analyses, men, women, elderly, smokers and hypertensives benefited from cholesterol lowering. There was no significant increase in non-cardiovascular causes of death. In the United States of America, the National Cholesterol Education Program (NCEP) Adult Treatment Panel, representing major health organizations, developed national guidelines on the detection, evaluation and treatment of high blood cholesterol in adults. In a given patient, the Panel recognizes the importance of weighing all cardiovascular disease risk factors including age (men > 45 years, postmenopausal women), family history of premature coronary disease, smoking, hypertension, diabetes and HDL-Cholesterol (< 35 mg/dl) in determining how aggressive therapy should be. The patient with manifest coronary heart disease (CHD) is given a special position as such patients are at highest risk for recurrent events. Major goals of therapy are to lower the LDL-Cholesterol to 2.6 mM/L (< 100 mg/dl) in the CHD patient. In non-CHD patients with two or more risk factors, the LDL-Cholesterol goal is 3.4 mM/L (130 mg/dl). In those with fewer risk factors, the goal is 4.2 mM/L (160 mg/dl). These guidelines should be modified as appropriate for Singapore. Patients with elevated triglycerides usually have low HDL-Cholesterol levels and often represent a heterogeneous group who may have other concurrent abnormalities including the presence of small dense LDL, insulin resistance, hypertension, obesity, overt diabetes and combined hyperlipidemia. Such patients merit individualized treatment. The prevalence of this syndrome may be more common in Singapore and requires further investigation. Current therapeutic guidelines emphasize the need for weight loss and dietary restriction of total and especially saturated fat (< 7% to 10% total calories), cholesterol (< 200 to 300 mg/day), and exercise. (ABSTRACT TRUNCATED)
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PMID:Cholesterol and atherosclerosis: a contemporary perspective. 939 24

Treatment modalities in severe nephrotic syndrome have to consider (a) the underlying glomerular diseases as well as (b) the extrarenal complications. Occasionally acute renal failure develops on the basis of an unknown nephrotic syndrome; if a primary glomerular disease is diagnosed by biopsy, immunosuppressive therapy is optional. In type I and type II diabetes development of a severe nephrotic syndrome is usually not reversible. To avoid the rapid decline of renal function a consequent antihypertensive therapy is the treatment of choice in this stage of the disease. Treatment of primary glomerular diseases with severe (NS) includes frequently relapsing minimal change nephropathy (MCN) that can be treated with prednisolone 1 mg/kg/day until remission occurs. For prolongation of the remission cyclophosphamide 2 mg/kg/day for eight weeks, or alternatively cyclosporine A 3 to 5 mg/kg/day for six months, can be given. In steroid-resistant focal segmental glomerulosclerosis (FSGS) eight weeks of treatment with cyclophosphamide 2.5 mg/kg/day or six months treatment with cyclosporine A 3 to 5 mg/kg/day can induce a partial or complete remission in up to 20% of the patients. In membranous glomerulopathy with severe NS, one month of therapy with prednisolone followed by chlorambucil for one month (all together 6 months) improves the renal outcome of the patients compared to controls. Alternatively, cyclophosphamide 2 mg/kg/day plus 30 mg prednisolone/day can be given for a couple of months. Extrarenal complications of a severe NS are: (a) edema; (b) thromboembolism; and (c) lipid abnormalities. If nephrotic patients are resistant to orally administered loop diuretics, they should be treated in addition intravenously with hydrochlorothiazide p.o. Nephrotic patients with a serum albumin level < 20 g/liter should be routinely anticoagulated. Extensive hyperlipidemia in severe NS can be treated with HMG-CoA reductase inhibitors.
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PMID:Treatment of severe nephrotic syndrome. 947 89

The recent development of specific competitive inhibitors of the hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase such as lovastatin, simvastatin, pravastatin and fluvastatin has provided an important new and effective approach to the treatment of hyperlipidaemia and atherosclerosis. These agents are designed to be hepatoselective because the primary site of cholesterol synthesis is the liver and peripheral inhibition of cholesterol synthesis would be more likely to cause adverse drug effects. In this review, Bettina Hamelin and Jacques Turgeon discuss how specific physico-chemical and pharmacological properties (first-pass effect or carrier-mediated uptake) confer hepatoselectivity to either lipophilic or hydrophilic HMG-CoA reductase inhibitors.
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PMID:Hydrophilicity/lipophilicity: relevance for the pharmacology and clinical effects of HMG-CoA reductase inhibitors. 950 99


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