Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to assess differences in the intensity of exercise to attenuate postprandial lipemia (PPL). Thirteen healthy men (age 23.8 +/- 0.9 yr) participated in three random-ordered trials: in low-(25% peak oxygen consumption; Low) and moderate-intensity (65% peak oxygen consumption; Mod) exercise trials, which were completed 1 h before a high-fat meal (1.3 g fat/kg body mass), and a control (Con), fat meal only, trial. Venous blood samples were obtained before the fat meal, and at 2, 4, 6, 8, and 20 h after the fat meal. PPL in the Mod trial (267 +/- 50 mg.dl-1.8 h) was lower compared with that in either Con (439 +/- 81 mg.dl-1.8 h) or Low (403 +/- 91 mg.dl-1.8 h) trials (P < 0.05), whereas there was no difference in PPL between Con and Low trials (P > 0.05). High-density lipoprotein cholesterol (HDL-C) and HDL subtype 2 cholesterol were not different between or within trials (P > 0.05). Postprandial insulinemia was lower in the Mod trial (20.5 +/- 5.7 microIU.ml-1.8 h; P < 0.05), but not in the Low trial (31.4 +/- 4.7 microIU.ml-1.8 h), compared with that in the Con trial (34.9 +/- 5.0 microIU.ml-1.8 h). Postheparin lipoprotein lipase activity at 8 h was higher in the Low trial compared with that in either Con or Mod trials, whereas there were no differences between trials at 20 h. These results suggest that, when exercise is performed 1 h before a fat meal, only exercise of moderate but not of low intensity attenuates PPL and that this effect is not associated with changes in postheparin lipoprotein lipase activity.
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PMID:Effects of low and moderate exercise intensity on postprandial lipemia and postheparin plasma lipoprotein lipase activity in physically active men. 1294 25

There is a considerable body of experimental evidence that heparin is superior as an anticoagulant to any prothrombin depressing drugs. Furthermore its lipemia-clearing action affords other benefits which result from the removal of fat from the bloodstream. Important among these beneficial effects is the increased tissue and myocardial oxygen consumption which results from the injection of heparin in atherosclerotic patients. Because of these advantages of heparin over oral anticoagulants, the use of heparin as the sole anticoagulant for three weeks in patients with severe acute myocardial infarction was evaluated as opposed to the customary therapy where heparin is given for several days and then oral anticoagulants are used. The mortality in the dicoumarin treated group was 38 per cent, as compared with 28 per cent in the patients who received only heparin for three weeks.
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PMID:Heparin in acute myocardial infarction: observations indicating the potential advantages of using it as the sole anticoagulant in therapy. 1382 Mar 24

Accumulating evidence indicates that reactive oxygen species (ROS) play major roles in the initiation and progression of cardiovascular dysfunction associated with diseases such as hyperlipidemia, diabetes mellitus, hypertension, ischemic heart disease, and chronic heart failure. ROS produced by migrating inflammatory cells as well as vascular cells (endothelial cells, vascular smooth muscle cells, and adventitial fibroblasts) have distinct functional effects on each cell type. These include cell growth, apoptosis, migration, inflammatory gene expression, and matrix regulation. ROS, by regulating vascular cell function, can play a central role in normal vascular physiology, and can contribute substantially to the development of vascular disease.
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PMID:Reactive oxygen species in the vasculature: molecular and cellular mechanisms. 1458 Dec 95

In glomerular and tubulointerstitial disease, polymorphonuclear- and monocyte-derived reactive oxygen species may contribute to oxidative modification of proteins, lipids, and nucleic acids. In part, the processes instigated by reactive oxygen species parallel events that lead to the development of atherosclerosis. Myeloperoxidase (MPO), a heme protein and catalyst for (lipo)protein oxidation is present in these mononuclear cells. The ability of MPO to generate hypochlorous acid/hypochlorite (HOCl/OCl-) from hydrogen peroxide in the presence of chloride ions is a unique and defining activity for this enzyme. The MPO-hydrogen peroxide-chloride system leads to a variety of chlorinated protein and lipid adducts that in turn may cause dysfunction of cells in different compartments of the kidney. The aim of this article is to cover and interpret some experimental and clinical aspects in glomerular and tubulointerstitial diseases in which the MPO-hydrogen peroxide-chloride system has been considered an important pathophysiologic factor in the progression but also the attenuation of experimental renal disease. The colocalization of MPO and HOCl-modified proteins in glomerular peripheral basement membranes and podocytes in human membranous glomerulonephritis, the presence of HOCl-modified proteins in mononuclear cells of the interstitium and in damaged human tubular epithelia, the inflammation induced and exacerbated by MPO antibody complexes in necrotizing glomerulonephritis, and the presence of HOCl-modified epitopes in urine following hyperlipidemia-induced renal damage in rodents suggest that MPO is an important pathogenic factor in glomerular and tubulointerstitial diseases. Specifically, the interaction of MPO with nitric oxide metabolism adds to the complexity of actions of oxidants and may help to explain bimodal partly detrimental partly beneficial effects of the MPO-hydrogen peroxide-chloride system in redox-modulated renal diseases.
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PMID:Myeloperoxidase in kidney disease. 1463 18

Plasma membranes are fluid structures and the maintenance of fluidity is a prerequisite for function, viability, growth and reproduction of cells. Membrane fluidity is the reciprocal of membrane microviscosity, which in turn is inversely proportional to rotational and lateral diffusion rates of membrane components. In the absence of constraints most lipids and unrestrained integral proteins freely diffuse in the plane of the membrane with high diffusion coefficients. The fluid mosaic model of plasma membrane structure is essentially still valid but this model is by its nature a macroscopic one. At present, attention is focused on molecular structural details of protein-lipid interactions and on the static and dynamic structure of membrane proteins. Highly potent new macroscopic and microscopic methods have been developed to measure translational diffusion of membrane lipids and proteins. The microscopic methods can reveal diffusion via encounters between labeled molecules. Fluorescence anisotropy measurements are the most widely used techniques in biological research. The use of different permeant and non-permeant fluorophores have contributed much to a better understanding of the changes in the ordered states and motional freedom of the membrane phospholipids in different cells during development, aging and physiological functions as well as in pathological conditions. The application of fluorophores with non-random distribution have shed light on the asymmetrical changes between the outer and inner domain of the lipid bilayer and on the dynamics of 'flip-flop' in signal transduction. Membrane fluidity was shown to have a decisive role in the efficiency of ligand binding, in the outcome of direct cell to cell contacts and in the modulation of the activity of membrane enzymes. Cell filtrability reflects whole cell viscosity that can not always be correlated with the fine changes in membrane fluidity. Cell viscosity depends inter alia on the size and shape of the cells as well as on membrane rigidity. In contrast to this, membrane fluidity is only dependent on the freedom of mobility of the membrane constituents. Increased release of free radicals and reactive oxygen specie (ROS) affect membrane fluidity, cellular Ca2+ homeostasis, induce lipid peroxidation and finally cell death. Investigation of membrane fluidity proved to be a useful and sensitive additional method to obtain a better insight into the mechanisms by which different compounds, drugs and contact with foreign surfaces are affecting cellular functions. The measurements of membrane fluidity may gain more widespread use for monitoring the safety and efficacy of these actions. During the last few years, changes in membrane fluidity of blood cells have been reported during development and aging and as a result of physiological cell functions. Membrane fluidity changes have been described in thrombocythaemia, hyperlipidaemia, hypercholesterolaemia, hypertension, diabetes mellitus, obesity, septic conditions and in allergic and burnt patients, in alcoholics, in Alzheimer's disease and in schizophrenia. A short summary is given on red cell membrane fluidity changes in a Hungarian triosephosphate isomerase (TPI)-deficient family, reflecting how the very subtle changes in membrane fluidity can help to establish underlying biological differences between the clinical phenotypes of a severe enzyme (TPI) deficiency caused by the defect of a single gene in two brothers one with and one without neurological symptoms.
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PMID:Membrane fluidity of blood cells. 1465 48

The relentless decline in beta-cell function frequently observed in type 2 diabetic patients, despite optimal drug management, has variously been attributed to glucose toxicity and lipotoxicity. The former theory posits hyperglycemia, an outcome of the disease, as a secondary force that further damages beta-cells. The latter theory suggests that the often-associated defect of hyperlipidemia is a primary cause of beta-cell dysfunction. We review evidence that patients with type 2 diabetes continually undergo oxidative stress, that elevated glucose concentrations increase levels of reactive oxygen species in beta-cells, that islets have intrinsically low antioxidant enzyme defenses, that antioxidant drugs and overexpression of antioxidant enzymes protect beta-cells from glucose toxicity, and that lipotoxicity, to the extent it can be attributable to hyperlipidemia, occurs only in the context of preexisting hyperglycemia, whereas glucose toxicity can occur in the absence of hyperlipidemia.
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PMID:Beta-cell glucose toxicity, lipotoxicity, and chronic oxidative stress in type 2 diabetes. 1474 76

Mitochondriopathies (MCPs) are either due to sporadic or inherited mutations in nuclear or mitochondrial DNA located genes (primary MCPs), or due to exogenous factors (secondary MCPs). MCPs usually show a chronic, slowly progressive course and present with multiorgan involvement with varying onset between birth and late adulthood. Although several proteins with signalling, assembling, transport, enzymatic function can be impaired in MCP, most frequently the activity of the respiratory chain (RC) protein complexes is primarily or secondarily affected, leading to impaired oxygen utilization and reduced energy production. MCPs represent a diagnostic challenge because of their wide variation in presentation and course. Systems frequently affected in MCP are the peripheral nervous system (myopathy, polyneuropathy, lactacidosis), brain (leucencephalopathy, calcifications, stroke-like episodes, atrophy with dementia, epilepsy, upper motor neuron signs, ataxia, extrapyramidal manifestations, fatigue), endocrinium (short stature, hyperhidrosis, diabetes, hyperlipidaemia, hypogonadism, amenorrhoea, delayed puberty), heart (impulse generation or conduction defects, cardiomyopathy, left ventricular non-compaction heart failure), eyes (cataract, glaucoma, pigmentary retinopathy, optic atrophy), ears (deafness, tinnitus, peripheral vertigo), guts (dysphagia, vomiting, diarrhoea, hepatopathy, pseudo-obstruction, pancreatitis, pancreas insufficiency), kidney (renal failure, cysts) and bone marrow (sideroblastic anaemia). Apart from well-recognized syndromes, MCP should be considered in any patient with unexplained progressive multisystem disorder. Although there is actually no specific therapy and cure for MCP, many secondary problems require specific treatment. The rapidly increasing understanding of the pathophysiological background of MCPs may further facilitate the diagnostic approach and open perspectives to future, possibly causative therapies.
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PMID:Mitochondriopathies. 1500 63

Diseases such as hypertension, atherosclerosis, hyperlipidemia, and diabetes are associated with vascular functional and structural changes including endothelial dysfunction, altered contractility and vascular remodeling. Cellular events underlying these processes involve changes in vascular smooth muscle cell (VSMC) growth, apoptosis/anoikis, cell migration, inflammation, and fibrosis. Many factors influence cellular changes, of which angiotensin II (Ang II) appears to be amongst the most important. The physiological and pathophysiological actions of Ang II are mediated primarily via the Ang II type 1 receptor. Growing evidence indicates that Ang II induces its pleiotropic vascular effects through NADPH-driven generation of reactive oxygen species (ROS). ROS function as important intracellular and intercellular second messengers to modulate many downstream signaling molecules, such as protein tyrosine phosphatases, protein tyrosine kinases, transcription factors, mitogen-activated protein kinases, and ion channels. Induction of these signaling cascades leads to VSMC growth and migration, regulation of endothelial function, expression of pro-inflammatory mediators, and modification of extracellular matrix. In addition, ROS increase intracellular free Ca2+ concentration ([Ca2+]i), a major determinant of vascular reactivity. ROS influence signaling molecules by altering the intracellular redox state and by oxidative modification of proteins. In physiological conditions, these events play an important role in maintaining vascular function and integrity. Under pathological conditions ROS contribute to vascular dysfunction and remodeling through oxidative damage. The present review focuses on the biology of ROS in Ang II signaling in vascular cells and discusses how oxidative stress contributes to vascular damage in cardiovascular disease.
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PMID:Reactive oxygen species and angiotensin II signaling in vascular cells -- implications in cardiovascular disease. 1527 29

Reactive oxygen species (ROS), including superoxide (*O2-), hydrogen peroxide (H2O2), and hydroxyl anion (OH-), and reactive nitrogen species, such as nitric oxide (NO) and peroxynitrite (ONOO-), are biologically important O2 derivatives that are increasingly recognized to be important in vascular biology through their oxidation/reduction (redox) potential. All vascular cell types (endothelial cells, vascular smooth muscle cells, and adventitial fibroblasts) produce ROS, primarily via cell membrane-associated NAD(P)H oxidase. Reactive oxygen species regulate vascular function by modulating cell growth, apoptosis/anoikis, migration, inflammation, secretion, and extracellular matrix protein production. An imbalance in redox state where pro-oxidants overwhelm anti-oxidant capacity results in oxidative stress. Oxidative stress and associated oxidative damage are mediators of vascular injury and inflammation in many cardiovascular diseases, including hypertension, hyperlipidemia, and diabetes. Increased generation of ROS has been demonstrated in experimental and human hypertension. Anti-oxidants and agents that interrupt NAD(P)H oxidase-driven *O2- production regress vascular remodeling, improve endothelial function, reduce inflammation, and decrease blood pressure in hypertensive models. This experimental evidence has evoked considerable interest because of the possibilities that therapies targeted against reactive oxygen intermediates, by decreasing generation of ROS and/or by increasing availability of antioxidants, may be useful in minimizing vascular injury and hypertensive end organ damage. The present chapter focuses on the importance of ROS in vascular biology and discusses the role of oxidative stress in vascular damage in hypertension.
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PMID:Reactive oxygen species in vascular biology: implications in hypertension. 1533 29

The endothelial generation of reactive oxygen species (ROS) is important both physiologically and in the pathogenesis of many cardiovascular disorders. ROS generated by endothelial cells include superoxide (O2-*), hydrogen peroxide (H2O2), peroxynitrite (ONOO-*), nitric oxide (NO), and hydroxyl (*OH) radicals. The O2-* radical, the focus of the current review, may have several effects either directly or through the generation of other radicals, e.g., H2O2 and ONOO-*. These effects include 1) rapid inactivation of the potent signaling molecule and endothelium-derived relaxing factor NO, leading to endothelial dysfunction; 2) the mediation of signal transduction leading to altered gene transcription and protein and enzyme activities ("redox signaling"); and 3) oxidative damage. Multiple enzymes can generate O2-*, notably xanthine oxidase, uncoupled NO synthase, and mitochondria. Recent studies indicate that a major source of endothelial O2-* involved in redox signaling is a multicomponent phagocyte-type NADPH oxidase that is subject to specific regulation by stimuli such as oscillatory shear stress, hypoxia, angiotensin II, growth factors, cytokines, and hyperlipidemia. Depending on the level of oxidants generated and the relative balance between pro- and antioxidant pathways, ROS may be involved in cell growth, hypertrophy, apoptosis, endothelial activation, and adhesivity, for example, in diabetes, hypertension, atherosclerosis, heart failure, and ischemia-reperfusion. This article reviews our current knowledge regarding the sources of endothelial ROS generation, their regulation, their involvement in redox signaling, and the relevance of enhanced ROS generation and redox signaling to the pathophysiology of cardiovascular disorders where endothelial activation and dysfunction are implicated.
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PMID:Endothelial cell superoxide generation: regulation and relevance for cardiovascular pathophysiology. 1547 99


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