Lipoproteins contain a core of hydrophobic lipids (triglycerides and cholesteryl esters) surrounded by a shell of hydrophilic lipids (phospholipids, unesterified cholesterol) and proteins (called apolipoproteins) that interact with body fluids. The plasma lipoproteins are divided into five major classes based on their relative density (Fig. 421-1 and Table 421-1): chylomicrons, very-low-density lipoproteins (VLDLs), intermediate-density lipoproteins (IDLs), low-density lipoproteins (LDLs), and high-density lipoproteins (HDLs). Each lipoprotein class comprises a family of particles that vary in density, size, and protein composition. Because lipid is less dense than water, the density of a lipoprotein particle is primarily determined by the amount of lipid per particle. Chylomicrons are the most lipid-rich and therefore least dense lipoprotein particles, whereas HDLs have the least lipid and are therefore the most dense lipoproteins. In addition to their density, lipoprotein particles can be ...
Lipoproteins contain a core of hydrophobic lipids (triglycerides and cholesteryl esters) surrounded by a shell of hydrophilic lipids (phospholipids, unesterified cholesterol) and proteins (called apolipoproteins) that interact with body fluids. The plasma lipoproteins are divided into five major classes based on their relative density (Fig. 27-1 and Table 27-1): chylomicrons, very-low-density lipoproteins (VLDLs), intermediate-density lipoproteins (IDLs), low-density lipoproteins (LDLs), and high-density lipoproteins (HDLs). Each lipoprotein class comprises a family of particles that vary in density, size, and protein composition. Because lipid is less dense than water, the density of a lipoprotein particle is primarily determined by the amount of lipid per particle. Chylomicrons are the most lipid-rich and therefore least dense lipoprotein particles, whereas HDLs have the least lipid and are therefore the most dense lipoproteins. In addition to their density, lipoprotein particles can be ...
Brauns lipoprotein (BLP, Lpp, or murein lipoprotein), found in some gram-negative cell walls, is one of the most abundant membrane proteins; its molecular weight is about 7.2 kDa. It is bound at its C-terminal end (a lysine) by a covalent bond to the peptidoglycan layer (specifically to diaminopimelic acid molecules) and is embedded in the outer membrane by its hydrophobic head (a cysteine with lipids attached). BLP tightly links the two layers and provides structural integrity to the outer membrane. The gene encoding Brauns lipoprotein initially produces a protein composed of 78 amino acids, which includes a 20 amino acid signal peptide at the amino terminus. The mature protein is 6 kDa in size. Three monomers of Lpp assemble into a coiled-coil trimer. Large amounts of Brauns lipoprotein is present, more than any other protein in E. coli. Unlike other lipoproteins, it is linked covalently to the peptidoglycan. Lpp connects the outer membrane to the peptidoglycan. Lpp is anchored to the outer ...
Background Cardiovascular disease risk increases when lipoprotein metabolism is dysfunctional. We have developed a computational model able to derive indicators of lipoprotein production, lipolysis, and uptake processes from a single lipoprotein profile measurement. This is the first study to investigate whether lipoprotein metabolism indicators can improve cardiovascular risk prediction and therapy management. Methods and Results We calculated lipoprotein metabolism indicators for 1981 subjects (145 cases, 1836 controls) from the Framingham Heart Study offspring cohort in which NMR lipoprotein profiles were measured. We applied a statistical learning algorithm using a support vector machine to select conventional risk factors and lipoprotein metabolism indicators that contributed to predicting risk for general cardiovascular disease. Risk prediction was quantified by the change in the Area-Under-the-ROC-Curve (ΔAUC) and by risk reclassification (Net Reclassification Improvement (NRI) and Integrated
Atherosclerosis is the main killer in the western world. Current clinical praxis relies on the usage of total lipoproteins as markers for atherosclerosis, even though deaths occur in people with normal lipoprotein blood profiles. Each lipoprotein fraction presents a wide variability in both composition and structure that needs to be thoroughly assessed for more accurate use of these particles as biomarkers in the diagnostics of atherosclerosis. In this PhD project, the lipoprotein structure, composition and dynamics at model blood vessel surfaces will be investigated and correlated to the risk of developing atherosclerosis. Mapping of the lipoprotein structure will be done by small angle neutron and X-ray scattering while the compositional analysis will be done by proteomics and lipidomics, apart from biochemical assays. Despite of the importance of charting out lipid dynamics to exchange fat (lipoproteins carry fats in the body), only a few studies to date have addressed this point. We have ...
Cholesterol is minimally soluble in water; it cannot dissolve and travel in the water-based bloodstream. Instead, it is transported in the bloodstream by lipoproteins that are water-soluble and carry cholesterol and triglycerides internally. The apolipoproteins forming the surface of the given lipoprotein particle determine from what cells cholesterol will be removed and to where it will be supplied.. The largest lipoproteins, which primarily transport fats from the intestinal mucosa to the liver, are called chylomicrons. They carry mostly fats in the form of triglycerides. In the liver, chylomicron particles release triglycerides and some cholesterol. The liver converts unburned food metabolites into very low density lipoproteins (VLDL) and secretes them into plasma where they are converted to intermediate density lipoproteins(IDL), which thereafter are converted to low-density lipoprotein (LDL) particles and non-esterified fatty acids, which can affect other body cells. In healthy individuals, ...
Tissue factor pathway inhibitor (TFPI) is a Kunitz-type inhibitor that regulates the initiation of tissue factor-mediated coagulation. Recent reports in the literature have described variable results using different methodologies for TFPI measurement. In this study, we used one clotting and two amidolytic methodologies to assess TFPI functional levels. The study groups included normal healthy donors as well as patients with acute hepatitis, diabetes, coronary artery bypass graft operations, deep vein thrombosis, and prior to and during heparin therapy. The aims were to compare the results obtained in normal plasma using different assay systems, to compare TFPI levels in a range of clinical samples, including those previously not determined using a clotting methodology, and to report TFPI levels in patient groups previously not investigated. The results clearly demonstrate poor correlation between functional TFPI values using the different methodologies, highlighting the requirement for ...
Aberrant metabolism of specific lipoprotein fractions, particularly LDL and HDL, is associated with atherosclerotic diseases and modulation of their plasma concentrations is a tenet of therapeutic strategies.30,31 Dysfunctional lipoprotein metabolism has also been implicated in human AAA formation, although associations have not been studied extensively.1 In this study, AngII-induced AAAs in multiple mouse models with different plasma lipoprotein distributions were used to determine whether facets of dyslipidemia were directly associated with AAA formation. We were unable to define any effect of reduced HDL-cholesterol concentrations, promoted by apoAI deficiency, on AngII-induced AAA formation in 2 mouse strains with dietary manipulations. However, our findings clearly demonstrated that hypercholesterolemia augmented the development of AngII-induced AAAs in mice. Changes in large-sized lipoprotein particles were associated with augmentation of AngII-induced AAAs. The only feature in common for ...
TY - JOUR. T1 - Effect of dietary triacylglycerol structure on lipoprotein metabolism. T2 - A comparison of the effects of dioleoylpalmitoylglycerol in which palmitate is esterified to the 2-or 1(3)-position of the glycerol. AU - Pufal, Deborah A. AU - Quinlan, Paul T. AU - Salter, Andrew M. PY - 1995/8/24. Y1 - 1995/8/24. N2 - The effect on lipoprotein metabolism of diets enriched in different isomers of dioleoylpalmitoylglycerol was studied. One diet contained fat in which palmitate was esterified to the two outer positions of the glycerol (OOP) and the other in which it was esterified to the middle carbon (OPO). The lipid composition of chylomicrons was similar in rats fed either fat blend. However, triacylglycerol (TAG) in chylomicrons from OPO fed animals was relatively enriched in palmitic acid, at the expense of stearic, oleic and linoleic acids. Silver phase HPLC and 2-positional analysis clearly demonstrated that the identity of the fatty acid in the 2-position was similar in both ...
Abstract: Lipoproteins were isolated, using preparative ultracentrifugation, from blood plasma of rabbits with alimentary hypercholesterolemia. Alterations in the lipoprotein structure were studied by means of light-dispersion, intrinsic fluorescence of the protein component in lipoproteins and by fluorescence of probes--I-aniline naphthalene-8-sulfonate and pyrene. The structural alterations consisted in an increase of size of the lipoproteins of very low density, elevated viscosity of the lipid phase of lipoproteins of low and very low density as well as in occurrence of additional positively charged groups on the surface of these particles. Potential importance of the impairments observed in structure of atherogenic lipoproteins from blood plasma in atherogenesis is discussed ...
PubMed journal article Increased plasma levels of tissue factor pathway inhibitor (TFPI) after n-3 polyunsaturated fatty acids supplementation in patients with chronic atherosclerotic diseas were found in PRIME PubMed. Download Prime PubMed App to iPhone, iPad, or Android
Researchers plan to study the fat-rich particles, called lipoproteins, which circulate in the blood. This study is designed to improve understanding of normal, as well as abnormal, lipoprotein metabolism and the role it plays in the development of hardening of the arteries (atherosclerosis).. Patients participating in this study will receive injections of lipoproteins or apolipoproteins (the protein component of lipoproteins) that have been isolated and purified. These lipoproteins will be labeled with small amounts of radioactive material and sterilized before they are injected into the patient.. Patients participating in the study will be required to have blood samples taken, and provide urine samples throughout the course of the study. In addition, patient will be required to follow a specially formulated diet. Patients will be weighed throughout the course of the study. ...
Dyslipidemias may account for the excess of cardiovascular mortality in end-stage renal disease (ESRD). Lipoprotein studies in ESRD patients are usually relative to prehemodialysis samples even if significative changes may occur after dialysis. In this study, we aimed to investigate the effects of ESRD on triglyceride-rich lipoproteins (TRL) subpopulations distribution and acute change following hemodialytic procedures, including the relative contribution of heparin administration. We selected a group of normolipidemic male middle-aged ESRD patients free of any concomitant disease affecting lipoprotein remnant metabolism compared with controls. We separated TRL subfractions according to density and apoE content and evaluated the changes of these particles after hemodialytic procedures with or without heparin. ESRD subjects had higher TRL subfractions, with the exception of apoE-rich particles, lower high-density lipoprotein (HDL) largest subclasses, and a smaller low-density lipoprotein peak ...
Introduction: Previous studies suggest lower concentrations of both total and HDL cholesterol to be predictive of depression. We therefore investigated the relationship of lipids and lipoprotein distribution with elevated depressive symptoms (EDS) in healthy men and women from the Multi-Ethnic Study of Atherosclerosis (MESA).. Methods: All MESA participants were 45-84 years old and free of clinically apparent cardiovascular disease at baseline. They were recruited from six United States communities and were followed up in person at four clinic visits over a 9.5-year period. EDS were defined as a Center for Epidemiological Studies Depression (CES-D) score ≥16 and/or use of antidepressant drugs. Lipoprotein distribution was determined from plasma by nuclear magnetic resonance spectroscopy.. Results: Among 4938 MESA participants without EDS at baseline, 1178 participants (23.9%) developed EDS during follow-up. In multivariable Cox regression analyses, lower total, LDL, and non-HDL cholesterol ...
To our knowledge, our study represents the first time that NMR lipoprotein variables have been assessed longitudinally in adults with SLE in relation to SLE disease activity and treatment. Each unit increase in the SLEDAI resulted in an increase in apoB-containing lipoproteins (total and small LDL-P) and a decline in apoB-containing HDL-P, which remained significant in multivariate analysis. Thus, more pathogenic lipoprotein variables occurred with SLE disease activity. In the general population, the atherogenic lipoprotein phenotype is often characterized by elevations in apoB-containing lipoproteins, including VLDL and small LDL-P concentrations, and lower levels of apoA-containing lipoproteins (HDL)27.. Prednisone use is often cited as a key factor in the development of atherosclerosis in SLE and is predictive of damage accrual and CV events2. In univariate and multivariate analyses, increases were demonstrated in VLDL variables and TGC with increases in the dose of prednisone. HDL was also ...
Class of lipoproteins that transport triglycerides from the intestine and liver to adipose and muscle tissues. Synthesized by the liver, they contain primarily triglycerides in their lipid cores, with some cholesterol esters. As their triglycerides are cleaved by endothelial lipoprotein lipase and transferred to hepatic tissues, the VLDL (very-low-density lipoprotein) particles lose most of their apolipoprotein C and become intermediate-density lipoproteins. ...
The adsorption of a number of lipoproteins, i.e., low-density lipoprotein (LDL), oxidized LDL (oxLDL), high-density lipoprotein (HDL), and lipoprotein (a), at silica and methylated silica as well as at the latter surface modified through adsorption of proteoheparan sulfate, was investigated with in situ ellipsometry at close to physiological conditions. It was found that LDL, oxLDL, HDL, and lipoprotein (a) all adsorbed more extensively at silica than at methylated silica. Upon exposure of the methylated silica surface to proteoheparan sulfate, this proteoglycan adsorbs through its hydrophobic moiety, thereby forming a layer similar to that in the biological system, with the polysaccharide chains forming brushes oriented toward the aqueous solution. Analogous to the biological system, both lipoprotein (a) and LDL were found to deposit at such surfaces, the latter particularly in the simultaneous presence of Ca2+. After HDL pre-exposure, however, no LDL deposition was observed, even at high LDL ...
Plasma lipoproteins (VLDL, LDL, Lp[a] and HDL) function primarily in lipid transport among tissues and organs. However, cumulative evidence suggests that lipoproteins may also prevent bacterial, viral and parasitic infections and are therefore a component of innate immunity. Lipoproteins can also de …
PubMed journal article Export of the outer membrane lipoprotein is defective in secD, secE, and secF mutants of Escherichia col were found in PRIME PubMed. Download Prime PubMed App to iPhone or iPad.
Bacteria outer membrane lipoprotein I: vaccine candidate; antigenically cross-reacts with all serotype strains of the International Antigenic Typing Scheme; amino acid sequence given in first source
The results of the present study strongly support the concept that GH has an important role in the physiological regulation of cholesterol and lipoprotein metabolism. The reversal of the disturbed lipoprotein pattern in 18-month-old male rats by a moderate dose of GH implies that, although other mechanisms may be involved, a relative GH deficiency contributes to the development of age-related hypercholesterolemia in this species. However, the present data do not permit any definite identification of a single mechanism by which GH exerts its effect in this situation. Instead, the data rather indicate that the pleiotropic effects of GH on lipoprotein metabolism result in compensatory adjustments of age-related changes at a number of regulatory steps.. The present data confirm and extend previous studies of cholesterol metabolism in the aging rat.13 14 35 36 37 38 39 Thus, a significant hypercholesterolemia was present in 18-month-old rats, whereas only a minor increase was detected in 12-month-old ...
Varbo et al1 pick up the concept that apolipoprotein B-containing lipoproteins cause atherosclerosis by at least 2 distinct mechanisms: a lipoprotein remnant-related pathway potentially involving systemic low-grade inflammation and a low-density lipoprotein (LDL)-related pathway without inflammation. This is in line with our observation that the triglyceride (TG) content of lipoproteins within densities from 1.0063 to 1.063 kg/L (LDL-TG) is more closely related to systemic inflammation and angiographic coronary artery disease than cholesterol in this fraction.2 Indeed, LDL-TG is a reflection of the accumulation of intermediate-density lipoproteins (1.0063-1.019 kg/L) and buoyant LDL-1 and LDL-2 (1.019-1.034 kg/L), which are metabolically remnant lipoproteins; 62% of LDL-TG is contributed by these fractions.2. For methodical reasons, however, the work by Varbo et al1 may lend only limited support to this concept. The postprandial metabolism of lipoproteins is a dynamic process,3 and the time ...
Recent clinical studies have revealed that increased serum triglyceride (TG) levels are closely related to atherosclerosis, independently of serum levels of high-density lipoproteins (HDL) and low-density lipoproteins (LDL). Among triglyceride-rich lipoproteins (TRLs), remnant lipoproteins (RLPs) are considered to be atherogenic and an independent coronary risk factor. We previously reported that monocytes cultured in the presence of RLPs increased their adhesion to vascular endothelial cells. The underlying mechanism involved activation of RhoA, a member of small GTP binding proteins, resulting in activation of focal adhesion kinase (FAK) and s1-integrin. It is also known that RLPs enter vessel walls. In another study, we reported that RLPs induced smooth muscle cell (SMC) proliferation, independently of oxidative stress. Recently, we identified the molecular mechanisms, in which RLPs from hypertriglyceridemic patients stimulated SMC proliferation via epidermal growth factor (EGF) receptor ...
Lipoprotein(a) (Lp(a)) is a distinctive cholesterol-rich lipoprotein complex in blood. Population studies show that Lp(a) levels are not normally distributed but are skewed towards low concentrations of ,10 mg/dl−1.1 Only 20% of Caucasians are thought to have levels ,30 mg/dl−1, the threshold level nominated for cardiovascular disease (CVD) risk in both children and adults.1 Although Lp(a) takes the form of an independent risk factor,1 it is the combined elevated levels of Lp(a) and low-density lipoprotein cholesterol (LDL-C), or Lp(a) and fibrinogen (Fg) that is thought to have the greatest detrimental effect.2 3. We determined the Lp(a) concentrations in schoolchildren aged 12-13 years in South Wales, as well as the percentage of children exhibiting ...
HDL, known as the "good cholesterol," is an important lipoprotein in diagnosing cardiovascular disease. Its abundance in the bloodstream is considered to be a sign of good cardiovascular health, because HDL carries away cholesterol.. Ever since the discovery in 1949 that lipoproteins can be separated and isolated in an ultracentrifuge, spinning lipoproteins like HDL at speeds of 40,000 rpm or greater has been the norm. Samples often get spun at speeds of 65,000 to 120,000 rpm within 48 hours to hasten the isolation process.. But there have been whispers in the lipid community that the high speeds damage the molecules. So a trio of researchers at UCLA, led by Verne Schumaker, decided to see how speed affects HDL. "The phenomenon of HDL potentially exhibiting sensitivity to the ultracentrifuge speed is sometimes mentioned between lipoprotein researchers," says Munroe, the first author on the paper. "However, there was little in the literature describing this phenomenon.". In their JLR paper, ...
TY - JOUR. T1 - Characterization of lipoprotein profiles in patients with hypertriglyceridemic Fredrickson-Levy and Lees dyslipidemia phenotypes. T2 - The very large database of Lipids studies 6 and 7. AU - Quispe, Renato. AU - Hendrani, Aditya D.. AU - Baradaran-Noveiry, Behnoud. AU - Martin, Seth S.. AU - Brown, Emily. AU - Kulkarni, Krishnaji R.. AU - Banach, Maciej. AU - Toth, Peter P.. AU - Brinton, Eliot A.. AU - Jones, Steven R.. AU - Joshi, Parag H.. PY - 2019. Y1 - 2019. N2 - Introduction: The association between triglycerides (TG) and cardiovascular diseases is complex. The classification of hypertriglyceridemic (HTG) phenotypes proposed by Fredrickson, Levy and Lees (FLL) helps inform treatment strategies. We aimed to describe levels of several lipoprotein variables from individuals with HTG FLL phenotypes from the Very Large Database of Lipids. Material and methods: We included fasting samples from 979,539 individuals from a contemporary large study population of US adults. Lipids ...
Methods are disclosed which separate and identify lipoproteins in biological samples. An ultracentrifuge density gradient is used to separate lipoprotein fractions. The fractions are visualized, resulting in a lipoprotein profile. The fractions can be further analyzed by a wide array of laboratory and clinical methods. The lipoprotein profile can be used in clinical diagnoses and other medical applications ...
Methods RA patients naive to any type of biologic therapy starting anti-TNF therapy, were evaluated at two points (first, just before the first dose of the anti-TNF agent and second, at six months of stable anti-TNF therapy) according to a pre-established protocol including the following assessments of lipidic metabolism: Lipoprotein, and apolipoprotein A1 (ApoA1) and B (ApoB) levels (total and lipoprotein specific), levels of paroxonase 1 (PON1), HDL, LDL, VLDL and total cholesterol, triglycerides and phospholipids levels, as well as number of molecules of these lipids (mc, mt and mf respectively) in each lipoprotein, total mass (M) and number of particles (np) of the afore mentioned lipoproteins and levels of PCSK9 receptor. Inflammatory markers (ESR, hsCRP, Pentraxina 3 and SAA) and disease activity by joints counts and DAS28 index were also performed. Standard statistical tests were used for comparing both assessments.. ...
Lipoprotein Analysis (A Practical Approach) at AbeBooks.co.uk - ISBN 10: 0199631921 - ISBN 13: 9780199631926 - Oxford University Press - 1992 - Softcover
Lipoprotein a p a repre-sents a class of lipoproteins with some structural similarity to low density lipoprotein LDL, but containing a unique apoprotein, apoprotein a. First reported in 1963, Lp a is now considered to have an independent role in the development of atherosclerotic lesions. The level of Lp a in the blood is under strong genetic...
TY - JOUR. T1 - Oxidized lipoproteins and endothelium. AU - Pirillo, Angela. AU - Zhu, Weimin. AU - Norata, Giuseppe D.. AU - Zanelli, Tiziano. AU - Barberi, Laura. AU - Roma, Paola. AU - Catapano, Alberico L.. PY - 2000. Y1 - 2000. N2 - Endothelium is an early target of pro-atherosclerotic events, which may result in functional and morphological perturbations. Oxidized low density lipoproteins, an atherogenic factor with strong cytotoxicity, may potentially contribute to altered endothelial function through the activation of a stress response, which would rescue cells to full vitality, or, conversely, by leading to cell death. Evidence is presented here for the ability of chemically oxidized low density lipoproteins to induce the synthesis of the inducible form of heat shock protein 70 in cultured human endothelial cells, and for the association of epitopes of these modified lipoproteins with apoptotic endothelial cells in aortic sections from hypercholesterolemic rabbits.. AB - Endothelium is ...
Strong correlations between plasma lipoprotein concentrations and the risk of stroke have never been clearly established. Unlike coronary heart disease, there is no significant direct relation between an increased risk of stroke and increased plasma total cholesterol or low density lipoprotein (LDL) cholesterol; nor is there an inverse relation with high density lipoprotein (HDL) cholesterol.1 Indeed, an inverse relation exists between total cholesterol concentrations and cerebral haemorrhage.2. The reasons for this weak or absent relation are several. The most compelling is that virtually all coronary heart disease can be ascribed to coronary atheroma, whereas less than half the incidence of stroke is due to large vessel atheroma. Non-atheromatous causes such as cardiac arrhythmias, small cerebral artery disease, and cortical degeneration are responsible for most of the rest. Another is that, in general, coronary deaths occur at a younger age than strokes, so the population with raised plasma ...
BACKGROUND:. The study was part of the initiative Collaborative Projects (R01s) on Minority Health. The concept for the initiative was developed by the NHLBI staff after the 1993 Report of the Committee on Appropriations, House of Representatives, encouraged the NHLBI to establish minority centers to facilitate the diagnosis and treatment of cardiovascular diseases. The initiative was approved at the September 1992 National Heart, Lung, and Blood Advisory Council and released in October 1992.. Julian Marsh was one of three investigators in a collaborative program with Bonita Falkner as Program Coordinator.. DESIGN NARRATIVE:. In a sub-set of subjects with either high or low plasma insulin levels after a glucose challenge (insulin sensitive or insulin resistant), the investigators determined the fractional and absolute synthesis and catabolic rates of apolipoproteins B and A-I, the dominant lipoproteins of Low Density Lipoprotein (LDL) and High Density Lipoprotein (HDL). They used stable ...
This fasting blood test is used to measure Apolipoprotein A-I (APO I), a major protein component of high density lipoprotein (HDL) in blood plasma. APO-I is a major component of the high-density lipoprotein complex frequently referred to as the good cholesterol which helps to clear cholesterol from arteries. Apolipoprotein B is attached to the LDL cholesterol molecule whose major role is to carry cholesterol to the tissues. The measurement of APO-B is considered to be a better indicator of risk for arterial plaque than LDL cholesterol. Research indicates the Apolipoprotein I B ratio may be a better indicator of cardiovascular disease than other cholesterol measures ...
Results:. Age, blood pressure, and serum lipoprotein(a) levels were greater in patients with early renal failure than in those with normal renal function and were independently associated with the presence of decreased creatinine clearance. Serum lipoprotein(a) and creatinine clearance were inversely correlated. The prevalence of coronary artery, cerebrovascular, and peripheral vascular disease was greater in patients with early renal failure than in those with normal renal function. The frequency distribution of apolipoprotein(a) isoforms was similar in patients with normal and those with impaired renal function. ...
PURPOSE OF REVIEW: Previously, the endothelium was considered as a passive exchange barrier of lipoproteins between plasma and extravascular tissues. This dogma is challenged by recent findings on a dual relationship between lipoproteins and endothelial permeability. RECENT FINDINGS: LDL and HDL as well as apolipoprotein A-I pass the intact endothelium through transcytosis by processes, which involve caveolin-1, the LDL-receptor, ATP-binding cassette transporters A1 and G1 or scavenger receptor BI. Moreover, HDL help the endothelium to maintain structural integrity and hence selective permeability for biomolecules by keeping interendothelial junctions closed, by inhibiting endothelial cell apoptosis and by stimulating endothelial proliferation, migration and tube formation as well as the recruitment and differentiation of endothelial progenitor cells in damaged parts of the endothelium. Both apolipoprotein A-I and sphingosin-1-phosphate mediate many of the protective effects of HDL on the ...
LPP and LPP Plus™. Spectracells LPP™ test is the most advanced lipoprotein test currently available. Unlike traditional cholesterol tests, Spectracells LPP™ directly measures both the size and number of several classes of lipoprotein particles, including critical risk factors as cited by the National Cholesterol Education Program, giving an accurate assessment of cardiovascular risk.. Many patients understand that not all cholesterol is the same. There is the "good" HDL (High Density Lipoprotein) cholesterol and the "bad" LDL (Low Density Lipoprotein) cholesterol. However, different types of HDL and LDL exist and some are much more dangerous than others. The LPP™ test determines the specific number of particles in each lipoprotein subclass (HDL and LDL) for a much more accurate assessment of risk. For example, the LPP™ test measures RLP (remnant lipoprotein) and Lp(a), both very atherogenic, but with very different effective treatment options. A standard cholesterol test does not ...
We read with great interest Sechi and colleagues report (1) on increased serum lipoprotein(a) [Lp(a)] concentration in patients with early renal disease. We have also recently shown that patients with mild to moderate renal failure (n = 106) and creatinine clearance of 10 to 60 mL/min and no factors that influence lipoprotein metabolism (such as proteinuria [,0.5 g/24 h], hypoalbuminemia, glucose intolerance, and severe hyperparathyroidism) exhibit increased serum Lp(a) levels, along with the other more common lipid abnormalities seen in this population (2). In fact, the median serum Lp(a) level was significantly increased in patients compared with levels in 106 age- and sex-matched controls (20 mg/dL compared with 6.5 mg/dL; P , 0.01), whereas the percentage of patients with increased (,30 mg/dL) serum Lp(a) levels was significantly higher in patients with impaired renal function than in the control group (35% compared with 11.8%; P , 0.01 ...
We describe the application of single molecule detection (SMD) technologies for the analysis of natural and synthetic transport systems. The need for advanced analytical procedures of these complex and important systems is presented with the specific enhancements afforded by SMD with flowing sample streams. In contrast to bulk measurements which yield only average values, measurement of individual species allows creation of population histograms form heterogeneous samples. The data are acquired in minutes and the analysis requires relatively small sample quantities. Preliminary data are presented from the analysis of low density lipoprotein, and multilamellar and unilamellar vesicles ...
F. Hammett, S. Saltissi, S. Rao, N. Miller, J. Coltart, B. Lewis; Plasma Lipoprotein Subclasses and Apoproteins as Predictors of Coronary Atherosclerosis in Man. Clin Sci (Lond) 1 February 1980; 58 (2): 31P. doi: https://doi.org/10.1042/cs058031Pa. Download citation file:. ...
Cholesterylester transfer protein (CETP) modulates the composition of various lipoproteins associated with cardiovascular disease. Despite its central role in lipoprotein metabolism, its mode of action is still not fully understood. Here we present a simple way to estimate CETP-mediated lipid fluxes between different lipoprotein fractions. The model derived adequately describes the observed findings, especially regarding low- and high dense lipoproteins (LDL and HDL), delivering correlation coefficients of R2 = 0.567 (p | 0.001) and R2 = 0.466 (p | 0.001), respectively. These estimated fluxes correlate best among all other measured concentrations and lipid per lipoprotein ratios to the observed fluxes. Our model approach is independent of CETP-actions exact mechanistic mode. It is simple and easy to apply, and may be a useful tool in revealing CETPs ambiguous role in lipid metabolism. The model mirrors a diffusion-like exchange of triglycerides between lipoproteins. Cholesteryl ester and
Serum cholesterol, triglycerides, apolipoprotein B (APOB)-containing lipoproteins (very low-density lipoprotein (VLDL), immediate-density lipoprotein (IDL), and low-density lipoprotein (LDL), lipoprotein A (LPA)) and the total cholesterol/high-density lipoprotein (HDL) cholesterol ratio are all connected in diseases. Here is the latest research. ...
Five Lol proteins are involved in the lipoprotein transport in Gram-negative bacteria. Crystal structures of a lipoprotein-specific periplasmic chaperone, LolA, and an outer membrane lipoprotein receptor, LolB from Escherichia coli were determined using diffraction data collected at the beamlines of SPring-8. Despite their dissimilar amino acid sequences (identity ~ 8%), the structures of LolA and LolB are strikingly similar to each other. Both have a hydrophobic cavity consisting of an unclosed β-barrel and an α-helical lid. The cavity represents a possible binding site for the lipid moiety of lipoproteins. However, the structural differences in size and shape of hydrophobic inner spaces between LolA and LolB are highly connected to the functional differences between two proteins. Furthermore, these structural differences between two proteins provide significant insights into the molecular mechanisms underlying the energy-independent transfer of lipoproteins from LolA to LolB, and from LolB ...
The advances of high throughput research in the biomedical domain have resulted in an onslaught of data being generated at an exponential rate. As a result, researchers face challenges in navigating through overwhelming amounts of information in order to derive relevant scientific insights. Ontologies address these issues by providing explicit description of biomedical entities and a platform for the integration of data, thereby enabling a more efficient retrieval of information. There have been major efforts in the development of biomedical ontologies in the recent years; however no such ontology exists for lipoproteins, which play a crucial role in various biological and cellular functions. Dysregulation in lipoprotein metabolism is significantly associated with an increased risk to cardiovascular disease, the leading cause of mortality in the world today. The aim of this paper is to propose a preliminary framework for Lipoprotein Ontology, with particular focus on the etiology and treatment ...
Atherogenesis is initiated by subendothelial accumulation (i.e. retention) of apolipoprotein B (apoB)-containing lipoproteins. Lipoprotein retention only occurs in specific vascular areas and is mediated by artery wall proteoglycans in the innermost layer of the artery (the arterial intima). In particular, proteoglycans with elongated glycosaminoglycan chains seem to play a crucial role in this process. The retained lipoproteins subsequently provoke an inflammatory response that ultimately leads to atherosclerosis. Atherogenic lipoproteins specifically locate in areas of intimal hyperplasia, characterised by accumulation of vascular smooth muscle cells and extracellular matrix. This thickened intima appears to act as a depot for extracellular lipids in the earliest initial stages of atherosclerosis. Furthermore, accumulation of apoB-containing triglyceride-rich lipoproteins in the postprandial state promotes the retention of remnant particles in the artery wall, in turn leading to accelerated ...
Atherogenesis is initiated by subendothelial accumulation (i.e. retention) of apolipoprotein B (apoB)-containing lipoproteins. Lipoprotein retention only occurs in specific vascular areas and is mediated by artery wall proteoglycans in the innermost layer of the artery (the arterial intima). In particular, proteoglycans with elongated glycosaminoglycan chains seem to play a crucial role in this process. The retained lipoproteins subsequently provoke an inflammatory response that ultimately leads to atherosclerosis. Atherogenic lipoproteins specifically locate in areas of intimal hyperplasia, characterised by accumulation of vascular smooth muscle cells and extracellular matrix. This thickened intima appears to act as a depot for extracellular lipids in the earliest initial stages of atherosclerosis. Furthermore, accumulation of apoB-containing triglyceride-rich lipoproteins in the postprandial state promotes the retention of remnant particles in the artery wall, in turn leading to accelerated ...
Principal Investigator:KATO Hisao, Project Period (FY):1997 - 1998, Research Category:Grant-in-Aid for Scientific Research (C), Section:一般, Research Field:Structural biochemistry
Because the apparent reduction in cardiovascular risk noted in nondiabetic populations that ingest diets rich in marine lipids containing ω-3 fatty acids is believed to result in part from their capacity to modify the composition and physicochemical behavior of lipoproteins, we sought to determine whether dietary supplementation with marine lipids might favorably affect lipoprotein composition in insulin-dependent diabetes mellitus (IDDM). Eight normolipidemic IDDM women (mean ± SD age 29.8 ± 4.7 yr) were studied before and 3 mo after receiving a marine-lipid concentrate (Super-EPA) containing 6 g ω-3 fatty acids and a total of 12 mg of cholesterol daily. Weight, insulin requirements, and glycosylated hemoglobin remained stable. After treatment, mean ± SD plasma triglyceride (TG) levels fell (before, 81.7 ± 22 mg/dl; after, 69.19 ± 17; P , 0.025). High-density lipoprotein2 (HDL2) cholesterol (before, 10.98 ± 5.45 mg/dl; after, 18.43 ± 7.93; P , 0.01), its major apolipoprotein A-I ...
Sometimes the end doesnt justify the means. In a recent paper in the Journal of Lipid Research, investigators describe how spinning high-density lipoproteins fast, a typical way to isolate them quickly, damages them. The finding suggests that the current understanding of the hydrodynamic properties and composition of HDL "is incorrect," states William Munroe at the University of California, Los Angeles.. HDL, known as the "good cholesterol," is an important lipoprotein in diagnosing cardiovascular disease. Its abundance in the bloodstream is considered to be a sign of good cardiovascular health because HDL carries away cholesterol.. Ever since the discovery in 1949 that lipoproteins can be separated and isolated in an ultracentrifuge, spinning lipoproteins like HDL at speeds 40,000 rpm or greater has been the norm. Samples often get spun at speeds of 65,000 to 120,000 rpm within 48 hours to hasten the isolation process.. But there have been whispers in the lipid community that the high speeds ...
Lipoprotein profile measured by NMR spectroscopy.(A) Bipolar LED pulse sequence 1H NMR spectra of a HIAE serum showing the fitting of the methyl band using seve