Sex, plasma lipoproteins, and atherosclerosis: prevailing assumptions and outstanding questions.

Science.gov (United States)

Godsland, I F; Wynn, V; Crook, D; Miller, N E

1987-12-01

We review the hypothesis that the incidence of coronary heart disease (CHD) is higher in men than in women due to differences in plasma lipoprotein risk factors between the sexes. Men and women appear to be equally susceptible to the effects of lipoprotein risk factors for CHD, and the difference between the sexes in lipoprotein risk factors for CHD appears to be consistent with their being, at least in part, responsible for the sex difference in CHD. This is apparent both when men and women of equal age are compared, and when age-related variations in the sex differences in plasma lipoproteins and CHD are considered. Differences between the sexes in lipoprotein concentrations are still present when sex differences in adiposity, cigarette smoking, physical activity, and diet are taken into account. Evidence relating these sex differences in CHD and lipoproteins to the effects of sex hormones is critically examined. It is commonly accepted that androgens induce changes in lipoprotein concentrations that would predispose towards CHD, whereas estrogens are held to have opposite effects. However, much of the evidence for this comes from studies of changes associated with administration of synthetic gonadal steroids or with changes in gonadal function. Studies of differences in lipoprotein metabolism in normal men and women are extremely limited. In males high-density lipoprotein (HDL) cholesterol levels fall at puberty, correlating with the rise in plasma testosterone concentrations. In females, HDL levels do not change at puberty, despite the rise in estrogen concentrations. Evidence for lipoprotein changes during the menopause, when estrogen levels decline, is equivocal. Similarly, the evidence for an increase in CHD incidence at the menopause is inconclusive. National mortality data indicate that the decreasing sex difference in CHD after 50 years of age is due to a declining rate of increase in men rather than to an acceleration in CHD incidence in women. In men

Formation of tissue factor activity following incubation of recombinant human tissue factor apoprotein with plasma lipoproteins

International Nuclear Information System (INIS)

Sakai, T.; Kisiel, W.

1990-01-01

Incubation of recombinant human tissue factor apoprotein (Apo-TF) with human plasma decreased the recalcified clotting time of this plasma in a time-and dose-dependent manner suggesting relipidation of the Apo-TF by plasma lipoproteins. Incubation of Apo-TF with purified preparations of human very low density, low density and high density lipoproteins resulted in tissue factor activity in a clotting assay. The order of effectiveness was VLDL greater than LDL much greater than HDL. Tissue factor activity generated by incubation of a fixed amount of Apo-TF with plasma lipoproteins was lipoprotein concentration-dependent and saturable. The association of Apo-TF with lipoprotein particles was supported by gel filtration studies in which 125 I-Apo-TF coeluted with the plasma lipoprotein in the void volume of a Superose 6 column in the presence and absence of calcium ions. In addition, void-volume Apo-TF-lipoprotein fractions exhibited tissue factor activity. These results suggest that the factor VIII-bypassing activity of bovine Apo-TF observed in a canine hemophilic model may be due, in part, to its association with plasma lipoproteins and expression of functional tissue factor activity

Plasma Cholesteryl Ester Transfer, But Not Cholesterol Esterification, Is Related to Lipoprotein-Associated Phospholipase A(2) : Possible Contribution to an Atherogenic Lipoprotein Profile

NARCIS (Netherlands)

Dullaart, Robin P. F.; Constantinides, Alexander; Perton, Frank G.; van Leeuwen, Jeroen J. J.; van Pelt, Joost L.; de Vries, Rindert; van Tol, Arie

Context: Plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) predicts incident cardiovascular disease and is associated preferentially with negatively charged apolipoprotein B-containing lipoproteins. The plasma cholesteryl ester transfer (CET) process, which contributes to low high-density

Proton nuclear magnetic resonance spectroscopy of plasma lipoproteins in malignancy

International Nuclear Information System (INIS)

Nabholtz, J.M.; Rossignol, A.; Farnier, M.; Gambert, P.; Tremeaux, J.C.; Friedman, S.; Guerrin, J.

1988-01-01

A recent study described a method of detecting malignant tumors by water-supressed proton nuclear magnetic resonance (1 H NMR) study of plasma. We performed a similar study of the W 1/2, a mean of the full width at half height of the resonances of the methyl and methylene groups of the lipids of plasma lipoproteins which is inversely related to the spin-spin apparent relaxation time (T 2 * ). W 1/2 values were measured at a fixed baseline width of 310 Hz. The study was prospective and blinded and comprised 182 subjects consisting of 40 controls, 68 patients with untreated malignancies, 45 with malignant tumors undergoing therapy and 29 benign tumor patients. No differences were seen between any groups that could serve as a basis for a useful clinical test. The major difficulty in the determination of W 1/2 was due to interference of metabolite protons (particularly lactate) within the lipoprotein resonance signal. Triglyceride level was seen to correlate inversely with W 1/2 within malignant patient groups. These discrepant results may be related to differing triglyceride-rich very low density lipoprotein (VLDL) levels in the ;atient populations of each study. We conclude that the water-suppressed 1H NMR of plasma lipoproteins is not a valid measurement for assessing malignancy. (orig.)

In vitro studies on the distribution of probucol among human plasma lipoproteins

International Nuclear Information System (INIS)

Urien, S.; Riant, P.; Albengres, E.; Brioude, R.; Tillement, J.P.

1984-01-01

The role of human plasma lipoproteins as carriers in the blood transport of the cholesterol-lowering and water-insoluble drug, probucol, was investigated in in vitro studies. [ 14 C]Probucol was incubated in whole human blood, a serum pool, individual diluted sera, and isolated protein and lipoprotein fractions. In whole blood, about 90% partitioned in plasma. Following ultracentrifugal fractionation of the serum, it was found that less than 5% distributed in the d greater than 1.20 protein fraction (albumin-rich fraction) and more than 95% in the lipoprotein fractions. The distribution of probucol in the lipoprotein fractions correlated with the lipoprotein total lipid volume under saturation conditions (incubation of isolated lipoprotein fractions) as well as nonsaturation conditions (fractionation of serum exposed to [ 14 C]probucol). Incubation of the albumin-rich fraction and of apolipoproteins originating from the isolated lipoprotein fractions showed that they account for a negligible part in the interaction of probucol with blood components. The probucol uptake of individual sera was shown to be correlated to the lipid content of the serum. When probucol was incubated in erythrocyte suspensions containing variable amounts of lipoproteins, probucol partitioned less in erythrocytes as the lipoprotein concentration increased in the suspension

[The role of structural heterogeneity of circulating lipids in the regulation of lipoprotein metabolism in the plasma and lymph in hypercholesterolemia in dogs].

Science.gov (United States)

Kosukhin, A B; Akhmetova, B S

1986-01-01

Fatty acid spectrum of lipoproteins was studied in intestinal steam lymph and blood plasma of dogs with alimentary hypercholesterolemia. Mechanism of cholesterol accumulation in blood plasma appears to relate to increase in content of cholesterol palmitate which is secreted from intestine into lymph and hydrolyzed slowly in liver tissue. Alterations in composition of fatty acid acyls of cholesterol esters, of phosphatidyl cholines and triacyl glycerides as well as effect of these alterations on the lecithin-cholesterol acyl-transferase reaction and lipoprotein lipolysis are discussed.

The signal peptide anchors apolipoprotein M in plasma lipoproteins and prevents rapid clearance of apolipoprotein M from plasma

DEFF Research Database (Denmark)

Christoffersen, Christina; Ahnström, Josefin; Axler, Olof

2008-01-01

Lipoproteins consist of lipids solubilized by apolipoproteins. The lipid-binding structural motifs of apolipoproteins include amphipathic alpha-helixes and beta-sheets. Plasma apolipoprotein (apo) M lacks an external amphipathic motif but, nevertheless, is exclusively associated with lipoproteins...... (mainly high density lipoprotein). Uniquely, however, apoM is secreted to plasma without cleavage of its hydrophobic NH(2)-terminal signal peptide. To test whether the signal peptide serves as a lipoprotein anchor for apoM in plasma, we generated mice expressing a mutated apoM(Q22A) cDNA in the liver (apoM......(Q22A)-Tg mice (transgenic mice)) and compared them with mice expressing wild-type human apoM (apoM-Tg mice). The substitution of the amino acid glutamine 22 with alanine in apoM(Q22A) results in secretion of human apoM without a signal peptide. The human apoM mRNA level in liver and the amount...

The effect of N-stearoylethanolamine on plasma lipid composition in rats with experimental insulin resistance

Directory of Open Access Journals (Sweden)

O. V. Onopchenko

2015-02-01

Full Text Available A model of insulin resistance (IR, induced by prolonged high fat diet with high content of saturated fats was used to investigate the effect of N-stearoylethanolamine (NSE on the composition of free fatty acids (FFA, plasma lipoprotein spectrum and content of proinflammatory cytokine TNFα in rats. The results of this work showed a rise in the content of monounsaturated fatty acids (18:1 n-9 and a reduction in the level of polyunsaturated fatty acids (20:4 n-6 in plasma of rats with experimental IR. These findings are accompanied by the increased TNFα production and significant changes in plasma lipoprotein profile of rats with the fat overload. Particularly, a decreased high-density lipoprotein (HDL cholesterol level and increased low-density (LDL and very low-density lipoprotein (VLDL cholesterol level were detected. The NSE administration to obese rats with IR restored the content of mono- and polyunsaturated FFA, increased HDL cholesterol content and reduced LDL cholesterol level. In addition, the IR rats treated with NSE showed normalization in the serum TNFα level. Our results showed the restoration of plasma lipid profile under NSE administration in rats with obesity-induced IR. Considering the fact that plasma lipid composition displays the lipid metabolism in general, the NSE actions may play a significant role in the prevention of IR-associated complications.

Ultracentrifugal and electrophoretic characteristics of the plasma lipoproteins of miniature schnauzer dogs with idiopathic hyperlipoproteinemia.

Science.gov (United States)

Whitney, M S; Boon, G D; Rebar, A H; Story, J A; Bottoms, G D

1993-01-01

To better characterize the idiopathic hyperlipoproteinemia of Miniature Schnauzer dogs, the plasma lipoproteins of 20 Miniature Schnauzers (MS) and 11 dogs of other breeds (DOB) were evaluated by ultracentrifugation, electrophoresis, and biochemical tests. Seventeen MS were healthy; 3 had diabetes mellitus. Plasma from 6 of 17 healthy and all 3 diabetic MS was visibly lipemic. Lipemia was slight to marked in healthy lipemic MS, and marked in diabetic ones. All DOB had clear plasma; 8 were healthy and 3 had diabetes. All healthy lipemic MS and diabetic lipemic MS had hypertriglyceridemia associated with excess very low density lipoproteins. Chylomicronemia was present in 4 of 6 healthy lipemic MS and all 3 diabetic lipemic MS. Lipoproteins with ultracentrifugal and electrophoretic characteristics of normal low density lipoprotein were lacking in 4 of 6 healthy lipemic MS. The lipoprotein patterns of 4 of 11 healthy nonlipemic MS were characterized by mild hypertriglyceridemia associated with increased very low density lipoproteins and a lack of lipoproteins with characteristics of normal low density lipoproteins. Lipoprotein patterns of diabetic DOB closely resembled those of healthy DOB; those of diabetic lipemic MS resembled those of markedly lipemic healthy lipemic MS. In conclusion, the hyperlipoproteinemia of Miniature Schnauzers is characterized by increased very low density lipoproteins with or without accompanying chylomicronemia; some affected dogs may have decreased low density lipoproteins.

Elevated plasma low-density lipoprotein and high-density lipoprotein cholesterol levels in amenorrheic athletes: effects of endogenous hormone status and nutrient intake.

Science.gov (United States)

Friday, K E; Drinkwater, B L; Bruemmer, B; Chesnut, C; Chait, A

1993-12-01

To determine the interactive effects of hormones, exercise, and diet on plasma lipids and lipoproteins, serum estrogen and progesterone levels, nutrient intake, and plasma lipid, lipoprotein, and apolipoprotein concentrations were measured in 24 hypoestrogenic amenorrheic and 44 eumenorrheic female athletes. When compared to eumenorrheic athletes, amenorrheic athletes had higher levels of plasma cholesterol (5.47 +/- 0.17 vs. 4.84 +/- 0.12 mmol/L, P = 0.003), triglyceride (0.75 +/- 0.06 vs. 0.61 +/- 0.03 mmol/L, P = 0.046), low-density lipoprotein (LDL; 3.16 +/- 0.15 vs. 2.81 +/- 0.09 mmol/L, P = 0.037), high-density lipoprotein (HDL; 1.95 +/- 0.07 vs. 1.73 +/- 0.05 mmol/L, P = 0.007), and HDL2 (0.84 +/- 0.06 vs. 0.68 +/- 0.04 mmol/L, P = 0.02) cholesterol. Plasma LDL/HDL cholesterol ratios, very low-density lipoprotein and HDL3 cholesterol, and apolipoprotein A-I and A-II levels were similar in the two groups. Amenorrheic athletes consumed less fat than eumenorrheic subjects (52 +/- 5 vs. 75 +/- 3 g/day, P = 0.02), but similar amounts of calories, cholesterol, protein, carbohydrate, and ethanol. HDL cholesterol levels in amenorrheic subjects correlated positively with the percent of dietary calories from fat (r = 0.42, n = 23, P = 0.045) but negatively with the percent from protein (r = -0.49, n = 23, P = 0.017). Thus, exercise-induced amenorrhea may adversely affect cardiovascular risk by increasing plasma LDL and total cholesterol. However, cardioprotective elevations in plasma HDL and HDL2 cholesterol may neutralize the risk of cardiovascular disease in amenorrheic athletes.

Native and Reconstituted Plasma Lipoproteins in Nanomedicine: Physicochemical Determinants of Nanoparticle Structure, Stability, and Metabolism.

Science.gov (United States)

Pownall, Henry J; Rosales, Corina; Gillard, Baiba K; Ferrari, Mauro

2016-09-01

Although many acute and chronic diseases are managed via pharmacological means, challenges remain regarding appropriate drug targeting and maintenance of therapeutic levels within target tissues. Advances in nanotechnology will overcome these challenges through the development of lipidic particles, including liposomes, lipoproteins, and reconstituted high-density lipoproteins (rHDL) that are potential carriers of water-soluble, hydrophobic, and amphiphilic molecules. Herein we summarize the properties of human plasma lipoproteins and rHDL, identify the physicochemical determinants of lipid transfer between phospholipid surfaces, and discuss strategies for increasing the plasma half-life of lipoprotein- and liposome-associated molecules.

Plasma lipids, lipoprotein composition and profile during induction and treatment of hepatic lipidosis in cats and the metabolic effect of one daily meal in healthy cats.

Science.gov (United States)

Blanchard, G; Paragon, B M; Sérougne, C; Férézou, J; Milliat, F; Lutton, C

2004-04-01

Anorexia in obese cats may result in feline hepatic lipidosis (FHL). This study was designed to determine plasma lipids and lipoprotein profiles in queens at different stages during experimental induction of FHL (lean, obese, FHL), and after 10 weeks of treatment. Results were compared with those obtained from lean queens of same age fed the same diet but at a maintenance level, once a day. Hepatic lipidosis led to an increase in plasma triacylglycerol (TG), very low density lipoprotein (VLDL) and low density lipoprotein (LDL), and an enrichment of LDL with TG and of high density lipoprotein (HDL) with cholesterol, suggesting that VLDL secretion is enhanced, VLDL and LDL catabolism is lowered, and lipoprotein exchanges are impaired in FHL. This study also showed that cholesterolaemia is increased in cats fed at a dietary rhythm of one meal per day compared to ad libitum feeding.

Konsumsi Daging Sapi Bali Dan Pengaruhnya Pada Profil Lipoprotein Plasma Tikus (CONSUMPTION OF BEEF BALI CATTLE AND IT’S EFFECTS ON RATS PLASMA LIPOPROTEIN PROFILE

Directory of Open Access Journals (Sweden)

I Nyoman Suarsana

2016-02-01

Full Text Available Consumption of beef in Indonesia is continuously increasing. Aside from being a source of protein, beef also contains all essential amino acids, vitamins, fats and cholesterol making it an ideal choice for consumers. This study aims to analyze the consumption of beef bali on rats plasma lipoprotein levels. A total of 15 male rats Spraque Dawlly average body weight of 90-100g was used in this study. They were sub-divided into five  groups: a control group, without treatment (I, fed- beef group was treated from 7th day (II,  fed-beef group was treated from 5th day (III,  fed-beef group was treated from 3th day (IV, and fed-beef group was treated from 1st day (V.  At the end of the experiment, i.e 9th days all groups of rats were euthanasia with cethamine-HCl. Blood was taken through the heart and placed in tubes containing EDTA to obtain plasma. Levels of  cholesterol, triglycerides,  HDL was analyzed by spectrophotometric method using cholesterol KIT (Ref10028, TGA (Ref10720P, and HDL (Ref10018. LDL levels were calculated using the formula: LDL= total cholesterol-(TG/5-HDL. The results showed that  rats  given beef bali cattle for 8 days was lead to increased plasma triglyceride levels significantly (P<0.05, while cholesterol, HDL (high density lipoprotein and LDL (low density lipoprotein plasma levels is not increased.

Isolation and characterization of human apolipoprotein M-containing lipoproteins

DEFF Research Database (Denmark)

Christoffersen, Christina; Nielsen, Lars Bo; Axler, Olof

2006-01-01

Apolipoprotein M (apoM) is a novel apolipoprotein with unknown function. In this study, we established a method for isolating apoM-containing lipoproteins and studied their composition and the effect of apoM on HDL function. ApoM-containing lipoproteins were isolated from human plasma...... with immunoaffinity chromatography and compared with lipoproteins lacking apoM. The apoM-containing lipoproteins were predominantly of HDL size; approximately 5% of the total HDL population contained apoM. Mass spectrometry showed that the apoM-containing lipoproteins also contained apoJ, apoA-I, apoA-II, apoC-I, apo...

Lipoproteins in Drosophila melanogaster—Assembly, Function, and Influence on Tissue Lipid Composition

Science.gov (United States)

Palm, Wilhelm; Sampaio, Julio L.; Brankatschk, Marko; Carvalho, Maria; Mahmoud, Ali; Shevchenko, Andrej; Eaton, Suzanne

2012-01-01

Interorgan lipid transport occurs via lipoproteins, and altered lipoprotein levels correlate with metabolic disease. However, precisely how lipoproteins affect tissue lipid composition has not been comprehensively analyzed. Here, we identify the major lipoproteins of Drosophila melanogaster and use genetics and mass spectrometry to study their assembly, interorgan trafficking, and influence on tissue lipids. The apoB-family lipoprotein Lipophorin (Lpp) is the major hemolymph lipid carrier. It is produced as a phospholipid-rich particle by the fat body, and its secretion requires Microsomal Triglyceride Transfer Protein (MTP). Lpp acquires sterols and most diacylglycerol (DAG) at the gut via Lipid Transfer Particle (LTP), another fat body-derived apoB-family lipoprotein. The gut, like the fat body, is a lipogenic organ, incorporating both de novo–synthesized and dietary fatty acids into DAG for export. We identify distinct requirements for LTP and Lpp-dependent lipid mobilization in contributing to the neutral and polar lipid composition of the brain and wing imaginal disc. These studies define major routes of interorgan lipid transport in Drosophila and uncover surprising tissue-specific differences in lipoprotein lipid utilization. PMID:22844248

In vitro production of beta-very low density lipoproteins and small, dense low density lipoproteins in mildly hypertriglyceridemic plasma: role of activities of lecithin:cholester acyltransferase, cholesterylester transfer proteins and lipoprotein lipase.

Science.gov (United States)

Chung, B H; Segrest, J P; Franklin, F

1998-12-01

As a model for the formation of beta-very low density lipoproteins (VLDL) and small, dense LDL by the intraplasma metabolic activities in vivo, lipoproteins in fresh plasma were interacted in vitro with endogenous lecithin:cholesterol acyltransferase (LCAT) and cholesterylester transfer proteins (CETP) and subsequently with purified lipoprotein lipase (LpL). The LCAT and CETP reactions in a mildly hypertriglyceridemic (HTG) plasma at 37 degrees C for 18 h resulted in (1) esterification of about 45% plasma unesterified cholesterol (UC), (2) a marked increase in cholesterylester (CE) (+129%) and a decrease in triglyceride (TG) (-45%) in VLDL, and (3) a marked increase of TG (+ 341%) with a small net decrease of CE (-3.6%) in LDL, causing a significant alteration in the TG/CE of VLDL (from 8.0 to 1.9) and of LDL (from 0.20 to 0.93). The LDL in LCAT and CETP-reacted plasma is larger and more buoyant than that in control plasma. In vitro lipolysis of control and LCAT and CETP-reacted plasma by LpL, which hydrolyzed >90% of VLDL-TG and about 50-60% of LDL-TG, converted most of VLDL in control plasma (>85%) but less than half (40%) of VLDL in LCAT and CETP-reacted plasma into the IDL-LDL density fraction and transformed the large, buoyant LDL in the LCAT and CETP-reacted plasma into particles smaller and denser than those in the control plasma. The remnants that accumulated in the VLDL density region of the postlipolysis LCAT and CETP-reacted plasma contained apo B-100 and E but little or no detectable apo Cs and consisted of particles having pre-beta and beta-electrophoretic mobilities. The inhibition of LCAT during incubation of plasma, which lessened the extent of alteration in VLDL and LDL core lipids, increased the extent of lipolytic removal of VLDL from the VLDL density region but lowered the extent of alteration in the size and density of LDL. The LCAT, CETP and/or LpL-mediated alterations in the density of LDL in normolipidemic fasting plasma were less pronounced

The effect of insulin deficiency on the plasma clearance and exchange of high-density-lipoprotein phosphatidylcholine in rats.

OpenAIRE

Martins, I J; Redgrave, T G

1992-01-01

Triolein/cholesteryl oleate/cholesterol/phosphatidylcholine emulsions designed to model the lipid composition of chylomicrons were injected intravenously into control and streptozotocin-treated insulin-deficient rats. As previously described for lymph chylomicrons, the emulsion triolein was hydrolysed and phosphatidylcholine was transferred to the plasma high-density lipoproteins (HDL). This mechanism was used to introduce a phospholipid label into HDL in vivo. The subsequent clearance of pho...

In vivo transfer of cholesteryl ester from high and low density plasma lipoproteins into human aortic tissue

International Nuclear Information System (INIS)

Stender, S.; Hjelms, E.

1988-01-01

For the study of cholesteryl ester transfer from different plasma lipoproteins into human aortic tissue, patients scheduled for reconstructive aortic surgery were intravenously injected with autologous in vitro labeled lipoproteins 20 to 24 hours before aortic intima-media samples were obtained during the operation. The injectate contained high density lipoproteins (d greater than 1.063) labeled with 3H-cholesteryl ester and lipoproteins of lower density (d less than 1.063) labeled with 14C-cholesteryl ester or lipoproteins with the opposite labeling. In 16 aortic tissue samples (some with visible atherosclerosis) from 11 normocholesterolemic patients, the aortic influx of total cholesteryl ester was 1 to 50 nmol x cm-2 x day-1. Some 39% +/- 3% (mean +/- SEM) of the influx was derived from high density lipoproteins, which in plasma accounted for only 22% +/- 2% (mean +/- SEM) of the esterified cholesterol. The findings suggest that: 1) esterified cholesterol from the two lipoprotein fractions in plasma enter the aortic intima by the same mechanism, and 2) influx of cholesteryl ester from the smaller, high density lipoproteins is greater than influx from the larger, lower density lipoproteins considering their concentrations in plasma. In some patients, the cholesterol content in the intima-media tissue with no visible atherosclerosis corresponded to only a few months of continuous cholesteryl ester influx. This time is short considering the age of the patients and, therefore, indicates that removal of esterified cholesterol from the intima-media is of major importance in preventing cholesterol deposition in the arterial wall

Evaluation of Plasma Lipoprotein (A Levels in Diabetic and Non Diabetic Indiviuals

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BA Jalai

2005-01-01

Full Text Available Introduction: Lipoprotein (a is a particle rich in cholesterol in human plasma and it is known as an independent risk factor for coronary artery disease. In addition to genetic background, other factors such as diabetes affect the plasma concentration of this lipoprotein as a risk factor. The aim of this study was evaluation and comparison of plasma concentration of Lp(a in type II diabetics and non diabetic individuals. Material and Methods: The study population included 180 diabetic patients who had referred to the Diabetic Research center of Yazd and 180 non diabetic individuals who were matched according to age and sex with the patient group. Blood samples were collected from the study groups in fasting condition. Glycated hemoglobin, glucose, lipids and lipoproteins were measured by routine laboratory methods and Lp(a assay was carried out by electro immunodiffusion. Results were analyzed with the use of SPSS program. Statistical tests included variance analysis, t-test for comparing lipids and lipoproteins, U-test for comparing Lp(a in the two groups and Pearson Correlation for determining of the variables with Lp(a. Results: Mean plasma concentratin of Lp(a in diabetic patients (Mean + SD 41.98+ 34.63 mg/dl was significantly higher than that of the control group (26.6 + 20.2 mg/dl (P<0.001. Mean concentration of cholesterol, triglyceride and LDL cholesterol in the patient group was higher but mean HDL cholesterol in control group was higher than patient group. However, no significant correlation was found between Lp(a and other variables in the patient and control groups. Conclusion: Plasma concentration of Lp(a in Diabetes Mellitus is increased independently. In diabetic patients, the risk of coronary artery disease may increase with increase in Lp(a.

The fibrate drug gemfibrozil disrupts lipoprotein metabolism in rainbow trout

International Nuclear Information System (INIS)

Prindiville, John S.; Mennigen, Jan A.; Zamora, Jake M.; Moon, Thomas W.; Weber, Jean-Michel

2011-01-01

Gemfibrozil (GEM) is a fibrate drug consistently found in effluents from sewage treatment plants. This study characterizes the pharmacological effects of GEM on the plasma lipoproteins of rainbow trout (Oncorhynchus mykiss). Our goals were to quantify the impact of the drug on: 1) lipid constituents of lipoproteins (phospholipids (PL), triacylglycerol (TAG), and cholesterol), 2) lipoprotein classes (high, low and very low density lipoproteins), and 3) fatty acid composition of lipoproteins. Potential mechanisms of GEM action were investigated by measuring lipoprotein lipase activity (LPL) and the hepatic gene expression of LPL and of the peroxisome proliferator-activated receptor (PPAR) α, β, and γ isoforms. GEM treatment resulted in decreased plasma lipoprotein levels (- 29%) and a reduced size of all lipoprotein classes (lower PL:TAG ratios). However, the increase in HDL-cholesterol elicited by GEM in humans failed to be observed in trout. Therefore, HDL-cholesterol cannot be used to assess the impact of the drug on fish. GEM also modified lipoprotein composition by reducing the abundance of long-chain n-3 fatty acids, thereby potentially reducing the nutritional quality of exposed fish. The relative gene expression of LPL was increased, but the activity of the enzyme was not, and we found no evidence for the activation of PPAR pathways. The depressing effects of GEM on fish lipoproteins demonstrated here may be a concern in view of the widespread presence of fibrates in aquatic environments. Work is needed to test whether exposure to environmental concentrations of these drugs jeopardizes the capacity of fish for reproduction, temperature acclimation or migratory behaviors.

Lipid and lipoprotein abnormalities in acute lymphoblastic leukemia survivors.

Science.gov (United States)

Morel, Sophia; Leahy, Jade; Fournier, Maryse; Lamarche, Benoit; Garofalo, Carole; Grimard, Guy; Poulain, Floriane; Delvin, Edgard; Laverdière, Caroline; Krajinovic, Maja; Drouin, Simon; Sinnett, Daniel; Marcil, Valérie; Levy, Emile

2017-05-01

Survivors of acute lymphoblastic leukemia (ALL), the most common cancer in children, are at increased risk of developing late cardiometabolic conditions. However, the mechanisms are not fully understood. This study aimed to characterize the plasma lipid profile, Apo distribution, and lipoprotein composition of 80 childhood ALL survivors compared with 22 healthy controls. Our results show that, despite their young age, 50% of the ALL survivors displayed dyslipidemia, characterized by increased plasma triglyceride (TG) and LDL-cholesterol, as well as decreased HDL-cholesterol. ALL survivors exhibited lower plasma Apo A-I and higher Apo B-100 and C-II levels, along with elevated Apo C-II/C-III and B-100/A-I ratios. VLDL fractions of dyslipidemic ALL survivors contained more TG, free cholesterol, and phospholipid moieties, but less protein. Differences in Apo content were found between ALL survivors and controls for all lipoprotein fractions except HDL 3 HDL 2 , especially, showed reduced Apo A-I and raised Apo A-II, leading to a depressed Apo A-I/A-II ratio. Analysis of VLDL-Apo Cs disclosed a trend for higher Apo C-III 1 content in dyslipidemic ALL survivors. In conclusion, this thorough investigation demonstrates a high prevalence of dyslipidemia in ALL survivors, while highlighting significant abnormalities in their plasma lipid profile and lipoprotein composition. Special attention must, therefore, be paid to these subjects given the atherosclerotic potency of lipid and lipoprotein disorders. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

Apolipoprotein (A) Isoform Distribution and Plasma Lipoprotein (a ...

African Journals Online (AJOL)

Plasma lipoprotein (a) Concentrations and apo(a) isoforms were determined in 101 healthy Nigerian subjects (M=63), F=38; age range 17-68 years), and coronary heart disease (CHD) patients (M=19, F=17, age range 30-79 years). Median Lp(a) level was 24.4 mg/di in the CHD patients and 22.1 mg/di in the controls.

Lipoprotein(a) and dietary proteins: casein lowers lipoprotein(a) concentrations as compared with soy protein1-3

DEFF Research Database (Denmark)

Nilausen, Karin Johanne; Meinertz, H.

1999-01-01

Lipoprotein(a), plasma lipoproteins, dietary proteins, soy protein, casein, liquid-formula, coronary artery disease, men, Denmark......Lipoprotein(a), plasma lipoproteins, dietary proteins, soy protein, casein, liquid-formula, coronary artery disease, men, Denmark...

The Association of Lipoprotein Changes and the Development of Plasma Leakage in Dengue Infection

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Leonard Nainggolan

2017-04-01

Full Text Available There’s interrelationship between infection and lipoprotein. This is a cohort prospective study which conducted November 2010 – February 2011. This study aimed to assess the changes of HDL-C, LDL-C, total cholesterol (TC, triglyceride (TG, in acute and critical phase of dengue infection and its association with plasma leakage. Subjects who had fever 48 hours or less and Dengue NS1 antigen test positive were admitted to Cipto Mangunkusumo Hospital Jakarta. We examined clinical and CBC daily; level of albumin, HDL-C, LDL-C, TC, TG; ultrasound to find ascites and pleural effusion. Among 51 subjects, 21 subjects (41% had plasma leakage. There were significant lower of HDL-C, LDL-C, and higher TG in critical phase than acute phase. In critical phase, subjects with plasma leakage had a significant lower HDL-C level [26.3 (8.2 vs 33.1 (12.1 mg/dL, p=0.029] but not for LDL-C, TC, and TG. They also had a significantly higher reduction in HDL-C [19.6 (9.1 vs 11.5 (5.8 mg/dL, p<0.0001] and TC [25.1 (20.0 vs 15.2 (14.5 mg/dL, 0.045] over the course of acute to critical phase. Lipoprotein changes during dengue infection were more pronounced among subjects who developed plasma leakage. The higher reduction in HDL-C is associated with the development of plasma leakage. Keywords: dengue infection, plasma leakage, cholesterol, lipoprotein, HDL   Hubungan antara Penurunan Kadar Kolesterol dengan Kejadian Kebocoran Plasma pada Infeksi Dengue   Abstrak Terdapat hubungan timbal balik antara infeksi dengan lipoprotein. Penelitian ini adalah penelitian kohort prospektif yang dilakukan November 2010 – Februari. Penelitian ini bertujuan untuk mengetahui perubahan kolesterol HDL, LDL, kolesterol total, dan trigliserid (TG pada fase akut dan kritis infeksi dengue serta hubungannya dengan kebocoran plasma. Subyek dengan demam 48 jam atau kurang dan uji Dengue NS1 antigen positif dirawat di RSUPN Cipto Mangunkusumo Jakarta. Dilakukan pemeriksaan klinis dan darah

Comparison of human plasma low- and high-density lipoproteins as substrates for lecithin: cholesterol acyltransferase.

Science.gov (United States)

Barter, P J; Hopkins, G J; Gorjatschko, L

1984-01-17

A recent observation that lecithin: cholesterol acyltransferase (EC 2.3.1.43) interacts with both low-density lipoproteins (LDL) and high-density lipoproteins (HDL) in human plasma is in apparent conflict with an earlier finding that the purified enzyme, while highly reactive with isolated HDL, was only minimally reactive with LDL. There is evidence, however, that lecithin: cholesterol acyltransferase may exist physiologically as a component of a complex with other proteins and that studies with the isolated enzyme may therefore provide misleading results. Consequently, interactions of the enzyme with isolated human lipoproteins have been re-examined in incubations containing lecithin: cholesterol acyltransferase as a component of human lipoprotein-free plasma in which a physiologically active complex of the enzyme with other proteins may have been preserved. In this system there was a ready esterification of the free cholesterol associated with both LDL and HDL-subfraction 3 (HDL3) in reactions that obeyed typical enzyme-saturation kinetics. For a given preparation of lipoprotein-free plasma the Vmax values with LDL and with HDL3 were virtually identical. The apparent Km for free cholesterol associated with HDL3 was 5.6 X 10(-5) M, while for that associated with LDL it was 4.1 X 10(-4) M. This implied that, in terms of free cholesterol concentration, the affinity of HDL3 for lecithin: cholesterol acyltransferase was about 7-times greater than that of LDL. When expressed in terms of lipoprotein particle concentration, however, it was apparent that the affinity of LDL for the enzyme was considerably greater than that of HDL3. When the lipoprotein fractions were equated in terms of lipoprotein surface area, the apparent affinities of the two fractions for the enzyme were found to be comparable.

Evaluation of plasma lipids and lipoproteins in nigerians suffering ...

African Journals Online (AJOL)

There are conflicting reports on the role of plasma lipids in depressive illness. Very little is known about the lipid and lipoprotein status in Nigerian adults suffering from depression. One hundred subjects consisting of sixty (60) depressed patients with mean age (40.3±12.3 yrs) and forty (40) apparently healthy controls ...

Human plasma phospholipid transfer protein increases the antiatherogenic potential of high density lipoproteins in transgenic mice

NARCIS (Netherlands)

M.J. van Haperen (Rien); A. van Tol (Arie); P. Vermeulen; M. Jauhiainen; T. van Gent (Teus); P.M. van den Berg (Paul); S. Ehnholm (Sonja); A.W.M. van der Kamp (Arthur); M.P.G. de Crom (Rini); F.G. Grosveld (Frank)

2000-01-01

textabstractPlasma phospholipid transfer protein (PLTP) transfers phospholipids between lipoprotein particles and alters high density lipoprotein (HDL) subfraction patterns in vitro, but its physiological function is poorly understood. Transgenic mice that overexpress

Serum and urinary lipoproteins in the human nephrotic syndrome: evidence for renal catabolism of lipoproteins

Energy Technology Data Exchange (ETDEWEB)

Shore, V.G.; Forte, T.; Licht, H.; Lewis, S.B.

1982-03-01

The urinary excretion of lipoproteins and the possibility of catabolic alterations on glomerular filtration were investigated in four nephrotic subjects difering in etiology, serum lipoprotein profile, and 24 hr urinary output of protein and lipids. The apolipoproteins and lipoproteins of urine were compared with those of serum with respect to distribution profile, physical properties, and composition. As expected from molecular sieving effects during glomerular filtration, the urinary HDL were more abundant than the lower density lipoproteins even when the plasma LDL was elevated markedly. Intact apolipoproteins were not found in the concentrated urinary fraction isolated by ultrafiltration between the limits of 10/sup 4/ and 5 x 10/sup 4/ daltons. On the basis of immunoreactivity, gel electrophoresis, and amino acid composition, apolipoproteins B and AI are the major and minor proteins, respectively, of urinary LDL, and apo B is the major protein of the urinary IDL and VLDL. Apolipoproteins AI, AII, CI, CIII, and possibly AIV were isolated from the urinary HDL. As much as 20% of the protein moiety of the urinary HDL appeared to be large apolipoprotien fragments with molecular weights and isoelectric points similar to those of apo CII and apo CIII. The lower density classes of urinary lipoproteins also appeared to have lost apo E and apo C's and to have undergone partial proteolysis.

Post-heparin plasma lipoprotein lipase, but not hepatic lipase activity, is related to plasma adiponectin in type 2 diabetic patients and healthy subjects

NARCIS (Netherlands)

De Vries, R; Wolffenbuttel, BHR; Sluiter, WJ; Van Tol, A; Dullaart, RPF

2005-01-01

The aim of this study was to determine the relationships of plasma adiponectin with post-heparin plasma lipoprotein lipase (LPL) and hepatic lipase (HL) activities, and to evaluate whether plasma adiponectin contributes to diabetes-associated dyslipidaemia. Plasma adiponectin, post-heparin plasma

Childhood obesity treatment; Effects on BMI SDS, body composition, and fasting plasma lipid concentrations.

Science.gov (United States)

Nielsen, Tenna Ruest Haarmark; Fonvig, Cilius Esmann; Dahl, Maria; Mollerup, Pernille Maria; Lausten-Thomsen, Ulrik; Pedersen, Oluf; Hansen, Torben; Holm, Jens-Christian

2018-01-01

The body mass index (BMI) standard deviation score (SDS) may not adequately reflect changes in fat mass during childhood obesity treatment. This study aimed to investigate associations between BMI SDS, body composition, and fasting plasma lipid concentrations at baseline and during childhood obesity treatment. 876 children and adolescents (498 girls) with overweight/obesity, median age 11.2 years (range 1.6-21.7), and median BMI SDS 2.8 (range 1.3-5.7) were enrolled in a multidisciplinary outpatient treatment program and followed for a median of 1.8 years (range 0.4-7.4). Height and weight, body composition measured by dual-energy X-ray absorptiometry, and fasting plasma lipid concentrations were assessed at baseline and at follow-up. Lipid concentrations (total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), non-HDL, and triglycerides (TG)) were available in 469 individuals (264 girls). Linear regressions were performed to investigate the associations between BMI SDS, body composition indices, and lipid concentrations. At baseline, BMI SDS was negatively associated with concentrations of HDL (p = 6.7*10-4) and positively with TG (p = 9.7*10-6). Reductions in BMI SDS were associated with reductions in total body fat percentage (pobesity during multidisciplinary childhood obesity treatment are accompanied by improvements in body composition and fasting plasma lipid concentrations. Even in individuals increasing their BMI SDS, body composition and lipid concentrations may improve.

Plasma lipoproteins and renal function during simvastatin treatment in diabetic nephropathy

DEFF Research Database (Denmark)

Hommel, E; Andersen, P; Gall, M A

1992-01-01

The aim of this study was to assess the effect of simvastatin on plasma lipoproteins and renal function in hypercholesterolaemic Type 1 (insulin-dependent) diabetic patients with diabetic nephropathy. Twenty-six hypercholesterolaemic (total cholesterol greater than or equal to 5.5 mmol/l) Type 1...

Elevated plasma YKL-40, lipids and lipoproteins, and ischemic vascular disease in the general population

DEFF Research Database (Denmark)

Kjaergaard, Alisa D; Johansen, Julia S; Bojesen, Stig E

2015-01-01

BACKGROUND AND PURPOSE: We tested the hypothesis that observationally and genetically elevated YKL-40 is associated with elevated lipids and lipoproteins and with increased risk of ischemic vascular disease. METHODS: We conducted cohort and Mendelian randomization studies in 96 110 individuals from...... the Danish general population, with measured plasma levels of YKL-40 (n=21 647), plasma lipids and lipoproteins (n=94 461), and CHI3L1 rs4950928 genotype (n=94 579). RESULTS: From 1977 to 2013, 3256 individuals developed ischemic stroke, 5629 ischemic cerebrovascular disease, 4183 myocardial infarction...

Enzymatic Modification of Plasma Low Density Lipoproteins in Rabbits: A Potential Treatment for Hypercholesterolemia

Science.gov (United States)

Labeque, Regine; Mullon, Claudy J. P.; Ferreira, Joao Paulo M.; Lees, Robert S.; Langer, Robert

1993-04-01

Phospholipase A_2 (EC 3.1.1.4) hydrolyzes certain phospholipids of low density lipoprotein (LDL). Plasma clearance of phospholipase A_2-modified human LDL is up to 17 times faster than that of native human LDL in hypercholesterolemic rabbits. Modification of blood lipoproteins of hypercholesterolemic rabbits was performed by using an extracorporeal circuit containing immobilized phospholipase A_2. After 90-min treatments, nearly 30% decreases in plasma cholesterol concentrations were observed. Erythrocyte, leukocyte, and platelet counts showed no net change after treatment. This technique does not require any fluid replacement or sorbent regeneration and offers a potential approach for lowering serum cholesterol and LDL levels.

Relationship between the concentrations of plasma phospholipid stearic acid and plasma lipoprotein lipids in healthy men.

Science.gov (United States)

Li, D

2001-01-01

This study investigated the correlation between the plasma phospholipid (PL) saturated fatty acid (SFA) concentration (as a surrogate marker of SFA intake) and plasma lipid and lipoprotein lipid concentrations in 139 healthy Australian men aged 20-55 years old with widely varying intakes of saturated fat (vegans, n=18; ovolacto vegetarians, n=43; moderate meat eaters, n=60; high meat eaters, n=18). Both the ovolacto vegetarian and vegan groups demonstrated significant decreases in plasma total cholesterol (TC), low-density-lipoprotein cholesterol (LDL-C) and triacylglycerol concentrations compared with both the high-meat-eater and moderate-meat-eater groups. Total SFA and individual SFA [palmitic acid (16:0), stearic acid (18:0) and arachidic acid (20:0)] in the plasma PL were significantly lower in both the ovolacto vegetarian and vegan groups than in both the high- and moderate-meat-eater groups, while myristic acid (14:0) was significantly lower in the vegans than in the high-meat-eaters. Bivariate analysis of the results showed that the plasma PL stearic acid concentration was strongly positively correlated with plasma TC (P<0.0001), LDL-C (P<0.0001) and triacylglycerol (P<0.0001), with r(2) values of 0.655, 0.518 and 0.43 respectively. In multiple linear regression, after controlling for potential confounding factors (such as exercise, dietary group, age, body mass index, plasma PL myristic acid, palmitic acid and arachidic acid, and dietary total fat, saturated fat, cholesterol, carbohydrate and fibre intake), the plasma PL stearic acid concentration was still strongly positively correlated with plasma TC (P<0.0001) and LDL-C (P=0.006) concentrations. Based on the present data, it would seem appropriate for the population to reduce their dietary total SFA intake rather than to replace other SFA with stearic acid.

An alternative procedure for incorporating radiolabelled cholesteryl ester into human plasma lipoproteins in vitro

International Nuclear Information System (INIS)

Roberts, D.C.K.; Miller, N.E.; Price, S.G.L.; Crook, D.; Cortese, C.; Ville, A. La; Masana, L.; Lewis, B.

1985-01-01

A simple method has been developed for labelling human plasma lipoproteins to high specific radioactivity with radioactive cholesteryl esters in vitro. After isolation by preparative ultracentrifugation, the selected lipoprotein was incubated for 30 min at 4 0 C in human serum (d > 1.215) that had been prelabelled with [4- 14 C]cholesteryl oleate or [1,2- 3 H]cholesteryl linoleate, and was then re-isolated by ultracentrifugation. All major lipoprotein classes were labelled by the procedure. Specific radioactivities of up to 18 d.p.m. .pmol -1 (46d.p.m. .ng -1 ) were achieved. When radiolabelled high-density lipoprotein was infused intravenously, the radioactive cholesteryl ester behaved in vivo indistinguishably from endogenous cholesteryl esters produced by the lecithin (phosphatidylcholine): cholesterol acyltransferase reaction. (author)

Consumption of nonfat milk results in a less atherogenic lipoprotein profile: a pilot study.

Science.gov (United States)

Hidaka, Hiroya; Takiwaki, Masaki; Yamashita, Mine; Kawasaki, Kenji; Sugano, Mitsutoshi; Honda, Takayuki

2012-01-01

An increase in plasma low-density lipoprotein (LDL) is a well-known risk factor in the development of atherosclerosis. Dairy consumption may lower the risk of atherosclerosis; however, studies on the effects of milk on cardiovascular risk factors are still scarce. We were interested in investigating whether the intake of milk improves the atherogenic lipoprotein profile. We investigated the effects of consuming whole or nonfat milk on plasma lipoprotein composition in healthy Japanese subjects as a pilot study. Normolipidemic subjects consumed 500 ml of whole milk (whole milk group; n=7) or nonfat milk (nonfat milk group; n=7) every day for 2 weeks. The consumption of nonfat milk resulted in a lowering of plasma triglyceride (TG) and phospholipid levels and TG level in high-density lipoprotein (HDL) and increased the plasma apolipoprotein (apo) C-III level. In addition, the TG/cholesterol ratios in HDL and LDL were significantly decreased, and LDL particles became larger. In contrast, the only changes observed following whole milk consumption were increases in the plasma levels of apoC-III and apoE. These findings suggest that consumption of nonfat milk, but not whole milk, may result in a less atherogenic lipoprotein profile, and that the constituents of nonfat milk may improve lipid metabolism.

Genetic determinants of LDL, lipoprotein(a), triglyceride-rich lipoproteins and HDL: concordance and discordance with cardiovascular disease risk

DEFF Research Database (Denmark)

Nordestgaard, Børge G; Tybjærg-Hansen, Anne

2011-01-01

To evaluate whether new and known genetic determinants of plasma levels of LDL cholesterol, lipoprotein(a), triglyceride-rich lipoproteins, and HDL cholesterol associate with the risk of cardiovascular disease expected from the effect on lipoprotein levels. Concordance or discordance of such gene......To evaluate whether new and known genetic determinants of plasma levels of LDL cholesterol, lipoprotein(a), triglyceride-rich lipoproteins, and HDL cholesterol associate with the risk of cardiovascular disease expected from the effect on lipoprotein levels. Concordance or discordance...

Effect of pistachio consumption on plasma lipoprotein subclasses in pre-diabetic subjects.

Science.gov (United States)

Hernández-Alonso, P; Salas-Salvadó, J; Baldrich-Mora, M; Mallol, R; Correig, X; Bulló, M

2015-04-01

Nuts have been demonstrated to improve several cardiovascular risk factors and the lipid profile in diabetic and pre-diabetic subjects. However, analysis of conventional serum lipid profiles does not completely explain the atherogenic risk associated with pre-diabetes. We therefore investigated whether chronic consumption of pistachio modifies the lipoprotein subclasses to a healthier profile in pre-diabetic subjects. Randomized cross-over clinical trial in 54 subjects with pre-diabetes. Subjects consumed a pistachio-supplemented diet (PD, 50% carbohydrates, 33% fat, including 57 g/d of pistachios daily) and a control diet (CD, 55% carbohydrates, 30% fat) for 4 months each, separated by a 2-week wash-out. Diets were isocaloric and matched for protein, fiber and saturated fatty acids. Nuclear magnetic resonance (NMR) was performed to determine changes in plasma lipoprotein subclasses. Small low-density lipoprotein particles (sLDL-P) significantly decreased after pistachio consumption compared to the nut-free diet (P = 0.023). The non-high-density lipoprotein particles (non-HDL-P i.e. VLDL-P plus LDL-P) significantly decreased under the PD compared to CD (P = 0.041). The percentage of sHDL-P increased by 2.23% after the PD compared with a reduction of 0.08% after the CD (P = 0.014). Consequently, the overall size of HDL-P significantly decreased in the PD (P = 0.007). Chronic pistachio consumption could modify the lipoprotein particle size and subclass concentrations independently of changes in total plasma lipid profile, which may help to explain the decreased risk of cardiovascular disease and mortality associated with those individuals who frequently consumed nuts. This study is registered at www.clinicaltrials.gov as NCT01441921. Copyright © 2015 Elsevier B.V. All rights reserved.

Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage

Energy Technology Data Exchange (ETDEWEB)

Frei, B. (Department of Nutrition, Harvard School of Public Health, Boston, MA (Unites States))

1991-12-01

The authors exposed human blood plasma and low-density lipoprotein (LDL) to many different oxidative challenges and followed the temporal consumption of endogenous antioxidants in relation to the initiation of oxidative damage. Under all types of oxidizing conditions, ascorbic acid completely protects lipids in plasma and LDL against detectable peroxidative damage as assessed by a specific and highly sensitive assay for lipid peroxidation. Ascorbic acid proved to be superior to the other water-soluble plasma antioxidants bilirubin, uric acid, and protein thiols as well as to the lipoprotein-associated antioxidants alpha-tocopherol, ubiquinol-10, lycopene, and beta-carotene. Although these antioxidants can lower the rate of detectable lipid peroxidation, they are not able to prevent its initiation. Only ascorbic acid is reactive enough to effectively intercept oxidants in the aqueous phase before they can attack and cause detectable oxidative damage to lipids.

Effect of 6 dietary fatty acids on the postprandial lipid profile, plasma fatty acids, lipoprotein lipase, and cholesterol ester transfer activities in healthy young men

DEFF Research Database (Denmark)

Tholstrup, T.; Sandstrøm, B.; Bysted, Anette

2001-01-01

, plasma fatty acids, and preheparin lipoprotein lipase and cholesterol ester transfer protein (CETP) activities. Design: Six test fats high (approximate to 43% by wt) in stearic acid, palmitic acid, palmitic + myristic acid, oleic acid, elaidic acid (trans 18:1), and linoleic acid were produced...... to the test-fat meals were observed for plasma lipoprotein triacylglycerol and cholesterol concentrations, plasma fatty acid concentrations, and lipoprotein lipase and CETP activities (diet x time interaction: 0.001 acids stearic and palmitic acids resulted......Background: There is increasing evidence that postprandial triacylglycerol-rich lipoproteins may be related to atherogenic risk. Objective: The objective was to investigate the effect of individual fatty acid intakes on postprandial plasma lipoprotein triacylglycerol and cholesterol concentrations...

Background diet and fat type alters plasma lipoprotein response but not aortic cholesterol accumulation in F1B Golden Syrian hamsters.

Science.gov (United States)

Dillard, Alice; Matthan, Nirupa R; Spartano, Nicole L; Butkowski, Ann E; Lichtenstein, Alice H

2013-12-01

Dietary modification alters plasma lipoprotein profiles and atherosclerotic lesion progression in humans and some animal models. Variability in response to diet induced atherosclerosis has been reported in hamsters. Assessed was the interaction between background diet composition and dietary fat type on aortic cholesterol accumulation, lipoprotein profiles, hepatic lipids and selected genes. F1B Golden Syrian hamsters (20/group) were fed (12 weeks) semi-purified or non-purified diets containing either 10 % (w/w) coconut oil or safflower oil and 0.15 % (w/w) cholesterol. The non-purified diets relative to semi-purified diets resulted in significantly higher TC (72 % [percent difference] and 38 %, coconut oil and safflower oil, respectively) and nHDL-C (84 and 61 %, coconut oil and safflower oil, respectively), and lower HDL-C (-47 and -45 %, coconut oil and safflower oil, respectively) concentrations. Plasma triacylglycerol concentrations in the hamsters fed the non-purified coconut oil-supplemented diets were three- to fourfold higher than non-purified safflower oil-supplemented, and both semi-purified diets. With the exception of HDL-C, a significant effect of fat type was observed in TC, nHDL-C and triacylglycerol (all P < 0.05) concentrations. Regardless of diet induced differences in lipoprotein profiles, there was no significant effect on aortic cholesterol accumulation. There was an inverse relationship between plasma nHDL-C and triacylglycerol, and hepatic cholesteryl ester content (P < 0.001). Diet induced differences in hepatic gene transcription (LDL receptor, apoB-100, microsomal transfer protein) were not reflected in protein concentrations. Although hamsters fed non-purified and/or saturated fatty acid-supplemented diets had more atherogenic lipoprotein profiles compared to hamsters fed semi-purified and/or polyunsaturated fatty acid-supplemented diets these differences were not reflected in aortic cholesterol accumulation.

Quantitative studies of transfer in vivo of low density, Sf 12-60, and Sf 60-400 lipoproteins between plasma and arterial intima in humans

International Nuclear Information System (INIS)

Shaikh, M.; Wootton, R.; Nordestgaard, B.G.; Baskerville, P.; Lumley, J.S.; La Ville, A.E.; Quiney, J.; Lewis, B.

1991-01-01

To assess the potential of various plasma lipoprotein classes to contribute to the lipid content of the arterial intima, influx and efflux of these plasma lipoprotein fractions into and from the intima of human carotid arteries were measured in vivo. While low density lipoprotein (LDL) is known to transfer from plasma into the arterial wall, there is less information on the atherogenic potential of lipoproteins of intermediate density (Sf 12-60) or of very low density (Sf 60-400). Aliquots of the same lipoprotein (LDL, Sf 12-60 lipoprotein particles, or Sf 60-400 lipoprotein particles) iodinated with iodine-125 and iodine-131 were injected intravenously 18-29 hours and 3-6 hours, respectively, before elective surgical removal of atheromatous arterial tissue, and the intimal clearance of lipoproteins, lipoprotein influx, and fractional loss of newly entered lipoproteins were calculated. Intimal clearance of Sf 60-400 particles was not detectable (less than 0.3 microliter x hr-1 x cm-2), whereas the average value for both LDL and Sf 12-60 lipoprotein particles was 0.9 microliter x hr-1 x cm-2. Since the fractional loss of newly entered LDL and Sf 12-60 lipoprotein particles was also similar, the results suggest similar modes of entry and exit for these two particles. However, due to lower plasma concentrations of Sf 12-60 lipoproteins as compared with LDL, the mass influx of cholesterol in the Sf 12-60 particles was on the order of one 10th of that in LDL, and that of apolipoprotein B was about one 20th

[Measurement of sialic acid from lipoproteins and human plasma by liquid chromatography-tandem mass spectrometry].

Science.gov (United States)

Guo, Shoudong; Sang, Hui; Yang, Nana; Kan, Yujie; Li, Fuyu; Li, Yu; Li, Fangyuan; Qin, Shucun

2014-11-01

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established to quantify sialic acid (N-acetylneuraminic acid, NANA) from lipoproteins and human plasma. The method was used to investigate the different contents of NANA from lipoproteins between diabetic with an average age of 51.6 years and healthy participants with an average age of 50.7 years. The NANA from lipoprotein samples was hydrolyzed by acetic acid (pH = 2) at 80 °C for 2 h and analyzed by the optimized LC-MS/MS method after high speed centrifugation and filtration. The limits of detection and quantification of NANA were 7.4 and 24.5 pg, respectively. The linear range was 2.5-80 ng/mL for NANA and the correlation coefficient (R2) was more than 0.998. The levels of NANA in the plasma of type II diabetics and healthy participants were (548.3 ± 88.9) and (415.3 ± 55.5) mg/L, respectively; and the levels of NANA from very low density lipoproteins (VLDL), low density lipoproteins (LDL), and high density lipoproteins (HDL) of the type II diabetics and the healthy participants were (4.91 ± 0.19), (6.95 ± 0.28), (3.61 ± 0.22) μg/mg and (2.90 ± 0.27), (7.03 ± 0.04), (2.40 ± 0.09) μg/mg, respectively. The sialic acid levels of VLDL and HDL from the type II diabetics were markedly higher than those of the corresponding healthy participants with the similar ages (P lipoproteins, and is reproducible and time saving.

Plasma Lp-PLA2 mass and apoB-lipoproteins that carry Lp-PLA2 decrease after sodium

NARCIS (Netherlands)

Constantinides, Alexander; Kerstens, Michiel N.; Dikkeschei, Bert D.; van Pelt, L. Joost; Tellis, Constantinos C.; Tselepis, Alexandros D.; Dullaart, Robin P. F.

2012-01-01

Eur J Clin Invest 2012; 42 (11): 12351243 Abstract Background Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a novel cardiovascular risk marker, which is predominantly complexed to apolipoprotein (apo) B-containing lipoproteins in human plasma. As increasing dietary sodium intake may decrease

Effect of dietary vegetable oils on the fatty acid profile of plasma lipoproteins in dairy cows.

Science.gov (United States)

Vargas-Bello-Pérez, Einar; Íñiguez-González, Gonzalo; Cancino-Padilla, Nathaly; Loor, Juan J; Garnsworthy, Philip C

2016-08-01

The aim of this study was to elucidate the effect of dietary supplementation of soybean oil (SO) and hydrogenated palm oil (HPO) on the transport of fatty acids (FA) within plasma lipoproteins in lactating and non-lactating cows. Three lactating and three non-lactating Holstein cows were used in two different 3 × 3 Latin square experiments that included three periods of 21 d. Dietary treatments for lactating cows consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (500 g/d per cow) or HPO (500 g/d per cow). For non-lactating cows, dietary treatments consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (170 g/d per cow) or HPO (170 g/d per cow). Compared with the control and SO diet, HPO addition increased (p lipoprotein (HDL). Total saturated FA were increased (p lipoprotein (VLDL). In non-lactating cows, the concentration of C18:0 was increased (p lipoprotein. Overall, it was found that distribution and transport of FA within the bovine plasma lipoproteins may be influenced by chain length and degree of unsaturation of dietary lipids. Also, the distribution of individual FA isomers such as C18:1trans-11 and C18:2cis-9,trans-11 may vary depending on the physiological state of the cow (lactating or non-lactating), and are increased in plasma (lactating cows) and the HDL (non-lactating cows) when cows are fed SO.

Effects of hormones on lipids and lipoproteins

Energy Technology Data Exchange (ETDEWEB)

Krauss, R.M.

1991-12-01

Levels of plasma lipids and lipoproteins are strong predictors for the development of atherosclerotic cardiovascular disease in postmenopausal women. In women, as in men, numerous factors contribute to variations in plasma lipoproteins that may affect cardiovascular disease risk. These include age, dietary components, adiposity, genetic traits, and hormonal changes. Each of these factors may operate to varying degrees in determining changes in plasma lipoprotein profiles accompanying menopause- Cross-sectional and longitudinal studies have suggested increases in levels of cholesterol, low density lipoproteins (LDL) and triglyceride-rich lipoproteins associated with menopause. High density lipoproteins (HDL), which are higher in women than men and are thought to contribute to relative protection of premenopausal women from cardiovascular disease, remain relatively constant in the years following menopause, although small, and perhaps transient reductions in the HDL{sub 2} subfraction have been reported in relation to reduced estradiol level following menopause. Despite these associations, it has been difficult to determine the role of endogenous hormones in influencing the plasma lipoproteins of postmenopausal women. In principle, the effects of hormone replacement should act to reverse any alterations in lipoprotein metabolism that are due to postmenopausal hormone changes. While there may be beneficial effects on lipoproteins, hormone treatment does not restore a premenopausal lipoprotein profile. Furthermore, it is not dear to what extent exogenous hormone-induced lipoprotein changes contribute to the reduced incidence of cardiovascular disease with hormone replacement therapy.

Childhood obesity treatment; Effects on BMI SDS, body composition, and fasting plasma lipid concentrations.

Directory of Open Access Journals (Sweden)

Tenna Ruest Haarmark Nielsen

Full Text Available The body mass index (BMI standard deviation score (SDS may not adequately reflect changes in fat mass during childhood obesity treatment. This study aimed to investigate associations between BMI SDS, body composition, and fasting plasma lipid concentrations at baseline and during childhood obesity treatment.876 children and adolescents (498 girls with overweight/obesity, median age 11.2 years (range 1.6-21.7, and median BMI SDS 2.8 (range 1.3-5.7 were enrolled in a multidisciplinary outpatient treatment program and followed for a median of 1.8 years (range 0.4-7.4. Height and weight, body composition measured by dual-energy X-ray absorptiometry, and fasting plasma lipid concentrations were assessed at baseline and at follow-up. Lipid concentrations (total cholesterol (TC, low-density lipoprotein (LDL, high-density lipoprotein (HDL, non-HDL, and triglycerides (TG were available in 469 individuals (264 girls. Linear regressions were performed to investigate the associations between BMI SDS, body composition indices, and lipid concentrations.At baseline, BMI SDS was negatively associated with concentrations of HDL (p = 6.7*10-4 and positively with TG (p = 9.7*10-6. Reductions in BMI SDS were associated with reductions in total body fat percentage (p<2*10-16 and percent truncal body fat (p<2*10-16. Furthermore, reductions in BMI SDS were associated with improvements in concentrations of TC, LDL, HDL, non-HDL, LDL/HDL-ratio, and TG (all p <0.0001. Changes in body fat percentage seemed to mediate the changes in plasma concentrations of TC, LDL, and non-HDL, but could not alone explain the changes in HDL, LDL/HDL-ratio or TG. Among 81 individuals with available lipid concentrations, who increased their BMI SDS, 61% improved their body composition, and 80% improved their lipid concentrations.Reductions in the degree of obesity during multidisciplinary childhood obesity treatment are accompanied by improvements in body composition and fasting plasma

Use of the TLX ultracentrifuge for the isolation of different density lipoproteins and effects of freeze/thawing of human plasma before ultracentrifugation.

Science.gov (United States)

Charlton-Menys, Valentine; Chobotova, Jelena; Durrington, Paul N

2008-01-01

Isolation of different density lipoproteins by ultracentrifugation can require lengthy centrifugation times and freeze/thawing of plasma may influence recovery. We isolated a range of lipoproteins using a preparative ultracentrifuge and the TLX micro-ultracentrifuge and determined the effect of freeze/thawing of plasma beforehand. In fresh plasma, there was no significant difference in results for small-dense low-density lipoprotein apolipoprotein B (LDL apoB) (density >1.044 g/mL) or cholesterol at density >1.006 g/mL. Freeze/thawing had no effect on closely correlated results for small-dense LDL apoB (r=0.85; pTLX micro-ultracentrifuge is a reliable alternative to the preparative ultracentrifuge and freeze/thawing has only a small effect on small-dense LDL apoB or high-density lipoprotein cholesterol.

Hyphenating size‐exclusion chromatography with electrospray mass spectrometry; using on‐line liquid‐liquid extraction to study the lipid composition of lipoprotein particles

Science.gov (United States)

Osei, Michael; Griffin, Julian L.

2015-01-01

Rationale Lipoproteins belong to the most commonly measured clinical biochemical parameters. Lipidomics is an orthogonal approach and aims to profile the individual lipid molecules that jointly form the lipoprotein particles. However, in the first step of the extraction of lipid molecules from serum, an organic solvent is used leading to dissociation of the lipoproteins. Thus far it has been impossible to combine lipidomics and lipoprotein analysis in one analytical system. Methods Human plasma was diluted in phosphate‐buffered saline (PBS) and injected onto a Superose 6 PC 3.2 column with PBS as a mobile phase to separate lipoproteins. The eluent was led to a Syrris FLLEX module, which also received CHCl3/MeOH (3:1). The two phases were mixed and subsequently separated using a Teflon membrane in an especially designed pressurized flow chamber. The organic phase was led to a standard electrospray source of an Orbitrap mass spectrometer. Results Size‐exclusion chromatography (SEC) has been commonly applied to separate lipoproteins and is considered a practical alternative to ultracentrifugation. Through the on‐line liquid‐liquid extraction method it becomes possible to obtained detailed mass spectra of lipids across different lipoprotein fractions. The extracted ion chromatograms of specific lipid signals showed their distribution against the size of lipoprotein particles. Conclusions The application of on‐line liquid‐liquid extraction allows for the continuous electrospray‐based mass spectral analysis of SEC eluent, providing the detailed lipid composition of lipoprotein particles separated by size. This approach provides new possibilities for the study of the biochemistry of lipoproteins. © 2015 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd. PMID:26443395

Data on plasma levels of apolipoprotein E, correlations with lipids and lipoproteins stratified by APOE genotype, and risk of ischemic heart disease

DEFF Research Database (Denmark)

Rasmussen, Katrine L.; Tybjærg-Hansen, Anne; Nordestgaard, Børge G

2016-01-01

Data on correlations of plasma apoE with levels of lipids and lipoproteins stratified by APOE genotypes as well as data exploring the association between plasma levels of apoE and risk of ischemic heart disease (IHD) are wanted. The present data on 91,695 individuals from the general population...... provides correlations between plasma levels of apoE and lipids and lipoproteins for the three APOE genotypes ε33, ε44 and ε22, representing each of the three apoE isoforms. Further, data on extreme groups of plasma apoE (highest 5%) versus lower levels of apoE at enrollment explores risk of IHD...... and myocardial infarction (MI) and is given as hazard ratios. In addition, IHD and MI as a function of apoE/high-density lipoprotein (HDL) cholesterol ratio, as well as data on lipids, lipoproteins and apolipoproteins are given as hazard ratios. Data is stratified by gender and presented for the Copenhagen...

Plasma lipids, lipoproteins, and triglyceride turnover in eu- and hypo-thyroid rats and rats on a hypocaloric diet.

Science.gov (United States)

Dory, L; Krause, B R; Roheim, P S

1981-08-01

Lipid and lipoprotein concentration, and triglyceride turnover were studied in control, thyroidectomized, and pair-fed control rats (pair-fed to match the food intake of the thyroidectomized rats). Thyroidectomy induced a significant increase in plasma cholesterol (and low density lipoprotein) concentrations and a decrease in plasma triglyceride (and very low density lipoprotein) concentrations. Changes in similar direction but of smaller magnitude were observed in the plasma of the pair-fed control rats. To further investigate triglyceride metabolism in these three groups of animals, triglyceride turnover was studied in fasted, unrestrained, and unanesthetized rats, following injection of [2-3H]glycerol. Peak incorporation of [2-3H]glycerol into plasma triglyceride occurred in all three groups of animals at 25 min after precursor administration, although the maximal incorporation was substantially lower in the thyroidectomized group than in either of the control groups. Thereafter, plasma triglyceride radioactivity decayed monoexponentially with a half-life of 24 +/- 1 min for both normal and pair-fed control rats, compared with the half-life of 41 +/- 3 min observed in the thyroidectomized rats. The calculated apparent fractional catabolic rates were thus 0.029 min-1 for both control groups and only 0.017 min-1 for the thyroidectomized animals. The apparent total catabolic rates of plasma triglyceride were 299 +/- 11, 138 +/- 11, and 48 +/- 4 micrograms triglyceride . min-1 for the normal controls, pair-fed controls, and thyroidectomized rats, respectively. These data further emphasize the importance of thyroid hormones in regulating plasma lipid and lipoprotein metabolism and, specifically, indicate that hypothyroidism results in a reduction of triglyceride secretion into, and the removal from, circulation. Furthermore, evidence was presented that the decreased caloric intake of the hypothyroid animals cannot, in itself, account for this observation.

The levels of plasma low density lipoprotein are independent of cholesterol ester transfer protein in fish-oil fed F1B hamsters

Directory of Open Access Journals (Sweden)

Davis Phillip J

2005-03-01

Full Text Available Abstract Background Cholesterol ester transfer protein (CETP plays a major role in regulating the levels of LDL- and HDL-cholesterol. We previously observed a fish-oil-induced elevation of low-density lipoprotein (LDL-and very-low-density lipoprotein (VLDL-cholesterol concentrations and a decrease in high-density lipoprotein (HDL-cholesterol concentration in F1B hamsters. The molecular mechanism/s by which fish oil induces hyperlipidaemic effect was investigated in this study. We examined whether the effects of dietary fish oil on plasma lipoprotein concentrations are due to fish-oil-induced alterations in plasma CETP activity. MIX diet, a diet supplemented with a mixture of lard and safflower oil, was used as the control diet. Results We found that fish oil feeding in hamsters reduced CETP mass as well as CETP activity. Increasing the dietary fat level of fish-oil from 5% to 20% (w/w led to a further decrease in CETP mass. Supplementation with dietary cholesterol increased both CETP mass and CETP activity in fish-oil and MIX-diet fed hamsters. However, there was no correlation between CETP mass as well as CETP activity and LDL-cholesterol concentrations. Conclusion These findings suggest that cholesterol ester transfer between HDL and LDL is not likely to play a major role in determining fish-oil-induced changes in LDL- and HDL-cholesterol concentrations in F1B hamsters. A possible role of reduced clearance of LDL-particles as well as dietary fat level and dietary cholesterol dependent changes in LDL-lipid composition have been discussed.

Lipoprotein profile, lipoprotein-associated phospholipase A2 and cardiovascular risk in hemodialysis patients.

Science.gov (United States)

Rolla, Roberta; De Mauri, Andreana; Valsesia, Ambra; Vidali, Matteo; Chiarinotti, Doriana; Bellomo, Giorgio

2015-12-01

Cardiovascular disease is the leading cause of morbidity and mortality in hemodialysis patients; the increased risk of cardiovascular disease is due to accelerated atherosclerosis, inflammation and impaired lipoprotein metabolism. We aimed to evaluate lipoprotein-associated phospholipase A2 (Lp-PLA2) and some pro-inflammatory aspects of the lipoprotein profile in dialyzed patients in order to evaluate the relationship with the accelerated atherosclerosis and vascular accidents. In 102 dialysis patients and 40 non-uremic controls, we investigated the lipoprotein plasma profile, high sensitivity C-reactive protein (CRP), ceruloplasmin and serum amyloid A protein (SAA), and followed patients for 1 year to analyze the risk of acute cardiovascular events. Total cholesterol, low-density lipoprotein and high-density lipoprotein plasma levels were significantly lower in uremic patients than controls, whereas CRP, SAA, ceruloplasmin, Lp-PLA2 and their ratio with apolipoprotein A1 were significantly higher. Patients with Lp-PLA2 levels >194 nmol/min/ml had more acute cardiovascular events than patients with lower values. Our results show that in dialysis subjects: (1) low-density lipoproteins show a more atherogenic phenotype than in the general population; (2) high-density lipoproteins are less anti-inflammatory; (3) Lp-PLA2 could potentially be used to evaluate cardiovascular risk.

Anthocyanins increase low-density lipoprotein and plasma cholesterol and do not reduce atherosclerosis in Watanabe Heritable Hyperlipidemic rabbits

DEFF Research Database (Denmark)

Nielsen, I. L. F.; Rasmussen, S.E.; Mortensen, Alicja

2005-01-01

a purified anthocyanin fraction front black currants, a black currant juice, probucol or control diet for 16 weeks. Purified anthocyanins significantly increased plasma cholesterol and low-density lipoprotein (LDL) cholesterol. Intake of black currant juice had no effect on total plasma cholesterol......, but lowered very-low-density lipoprotein (VLDL) cholesterol significantly. There were no significant effects of either purified anthocyanins or black currant juice on aortic cholesterol or development of atherosclerosis after 16 weeks. Probucol had no effect on plasma cholesterol but significantly lowered......, antioxidant enzymes, protein and lipid oxidation were not affected by any of the anthocyanin treatments. Adverse effects of purified anthocyanins were observed on plasma- and LDL-cholesterol. These effects were not observed with black currant juice, suggesting that black currants may contain components...

Changes in plasma low-density lipoprotein (LDL)- and high-density lipoprotein cholesterol in hypo- and hyperthyroid patients are related to changes in free thyroxine, not to polymorphisms in LDL receptor or cholesterol ester transfer protein genes

NARCIS (Netherlands)

Diekman, M. J.; Anghelescu, N.; Endert, E.; Bakker, O.; Wiersinga, W. M.

2000-01-01

Thyroid function disorders lead to changes in lipoprotein metabolism. Both plasma low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) increase in hypothyroidism and decrease in hyperthyroidism. Changes in LDL-C relate to altered clearance of LDL particles

Plasma levels of HDL subpopulations and remnant lipoproteins predict the extent of angiographically defined disease in post-menopausal women

Science.gov (United States)

The association of coronary heart disease (CHD) with subpopulations of triglyceride (TG)-rich lipoproteins and high-density lipoproteins (HDL) is established in men, but has not been well characterized in women. Plasma HDL subpopulation concentrations, quantified by 2-dimensional gel electrophoresis...

Genetics of Lipid and Lipoprotein Disorders and Traits.

Science.gov (United States)

Dron, Jacqueline S; Hegele, Robert A

2016-01-01

Plasma lipids, namely cholesterol and triglyceride, and lipoproteins, such as low-density lipoprotein (LDL) and high-density lipoprotein, serve numerous physiological roles. Perturbed levels of these traits underlie monogenic dyslipidemias, a diverse group of multisystem disorders. We are on the verge of having a relatively complete picture of the human dyslipidemias and their components. Recent advances in genetics of plasma lipids and lipoproteins include the following: (1) expanding the range of genes causing monogenic dyslipidemias, particularly elevated LDL cholesterol; (2) appreciating the role of polygenic effects in such traits as familial hypercholesterolemia and combined hyperlipidemia; (3) accumulating a list of common variants that determine plasma lipids and lipoproteins; (4) applying exome sequencing to identify collections of rare variants determining plasma lipids and lipoproteins that via Mendelian randomization have also implicated gene products such as NPC1L1 , APOC3 , LDLR , APOA5 , and ANGPTL4 as causal for atherosclerotic cardiovascular disease; and (5) using naturally occurring genetic variation to identify new drug targets, including inhibitors of apolipoprotein (apo) C-III, apo(a), ANGPTL3, and ANGPTL4. Here, we compile this disparate range of data linking human genetic variation to plasma lipids and lipoproteins, providing a "one stop shop" for the interested reader.

Effects of dietary coconut oil, butter and safflower oil on plasma lipids, lipoproteins and lathosterol levels.

Science.gov (United States)

Cox, C; Sutherland, W; Mann, J; de Jong, S; Chisholm, A; Skeaff, M

1998-09-01

The aim of this present study was to determine plasma levels of lathosterol, lipids, lipoproteins and apolipoproteins during diets rich in butter, coconut fat and safflower oil. The study consisted of sequential six week periods of diets rich in butter, coconut fat then safflower oil and measurements were made at baseline and at week 4 in each diet period. Forty-one healthy Pacific island polynesians living in New Zealand participated in the trial. Subjects were supplied with some foods rich in the test fats and were given detailed dietary advice which was reinforced regularly. Plasma lathosterol concentration (P safflower oil diets compared with butter diets. Plasma total cholesterol, HDL cholesterol and apoA-levels were also significantly (Psafflower oil compared with diets rich in butter and might be associated with lower production rates of apoB-containing lipoproteins.

Morphology and structure of lipoproteins revealed by an optimized negative-staining protocol of electron microscopy[S

Science.gov (United States)

Zhang, Lei; Song, James; Cavigiolio, Giorgio; Ishida, Brian Y.; Zhang, Shengli; Kane, John P.; Weisgraber, Karl H.; Oda, Michael N.; Rye, Kerry-Anne; Pownall, Henry J.; Ren, Gang

2011-01-01

Plasma lipoprotein levels are predictors of risk for coronary artery disease. Lipoprotein structure-function relationships provide important clues that help identify the role of lipoproteins in cardiovascular disease. The compositional and conformational heterogeneity of lipoproteins are major barriers to the identification of their structures, as discovered using traditional approaches. Although electron microscopy (EM) is an alternative approach, conventional negative staining (NS) produces rouleau artifacts. In a previous study of apolipoprotein (apo)E4-containing reconstituted HDL (rHDL) particles, we optimized the NS method in a way that eliminated rouleaux. Here we report that phosphotungstic acid at high buffer salt concentrations plays a key role in rouleau formation. We also validate our protocol for analyzing the major plasma lipoprotein classes HDL, LDL, IDL, and VLDL, as well as homogeneously prepared apoA-I-containing rHDL. High-contrast EM images revealed morphology and detailed structures of lipoproteins, especially apoA-I-containing rHDL, that are amenable to three-dimensional reconstruction by single-particle analysis and electron tomography. PMID:20978167

In vitro incorporation of radiolabeled cholesteryl esters into high and low density lipoproteins

International Nuclear Information System (INIS)

Terpstra, A.H.; Nicolosi, R.J.; Herbert, P.N.

1989-01-01

We have developed and validated a method for in vitro incorporation of radiolabeled cholesteryl esters into low density (LDL) and high density lipoproteins (HDL). Radiolabeled cholesteryl esters dissolved in absolute ethanol were mixed with LDL or HDL in the presence of lipoprotein-deficient serum (LPDS) as a source of core lipid transfer activity. The efficiency of incorporation was dependent on: (a) the core lipid transfer activity and quantity of LPDS, (b) the mass of added radiolabeled cholesteryl esters, (c) the length of incubation, and (d) the amount of acceptor lipoprotein cholesterol. The tracer incorporation was documented by repeat density gradient ultracentrifugation, agarose gel electrophoresis, and precipitation with heparin-MnCl2. The radiolabeling conditions did not affect the following properties of the lipoproteins: (1) chemical composition, (2) electrophoretic mobility on agarose gels, (3) hydrated density, (4) distribution of apoproteins on SDS gels, (5) plasma clearance rates, and (6) immunoprecipitability of HDL apoproteins A-I and A-II. Rat HDL containing radiolabeled cholesteryl esters incorporated in vitro had plasma disappearance rates identical to HDL radiolabeled in vivo

Plasma concentrations of lipids and lipoproteins in newborn kids and female Baladi goats during late pregnancy and onset of lactation.

Science.gov (United States)

Hussein, S A; Azab, M E

1998-01-01

Concentrations of blood lipids and some lipoproteins were investigated in normal female Baladi goats during late pregnancy, parturition and onset of lactation as well as in their newborn kids during the first two weeks of life. A total number of 60 herparinized blood samples was collected from does at 4, 3, 2 and 1 weeks pre-partum, day of parturition and at 1, 2, 3 and 4 weeks postpartum. In addition, blood samples were also collected from their newborn kids during the first two weeks of life (day of birth, 1 and 2 weeks of age). Plasma was separated and analyzed for concentration of total lipid, total cholesterol, triacylglycerols, phospholipids, non esterified fatty acids (NEFA) and some lipoproteins as high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C). The obtained results revealed that there was a significant decrease in plasma level of total lipids at one week after parturition. Plasma level of triaclyglycerols was significantly higher at 4, 3 and 2 weeks before parturition. This increase became very highly significant at one week before parturition. Meanwhile, plasma phospholipid concentrations showed a significant decrease at 3 weeks before parturition, followed by an significant increase at 2 and 3 weeks after parturition and highly significant increase at 4 weeks after parturition. The concentration of plasma NEFA showed a significant increase at 4 weeks before parturition followed by a very highly significant increase at 2 and 1 week before parturition. On the other hand plasma NEFA was non detected at 2, 3 and 4 weeks post-partum when compared with the value reported at day of parturition. Regarding plasma lipoprotein concentrations the obtained results showed that there was a significant increase in plasma HDL-C level at 2 and 3 weeks after parturition, followed by a very highly significant decrease at the fourth week post-partum. However, plasma LDL-C level showed a significant decrease at 3, 2 and 1 weeks

Automated Processing of Plasma Samples for Lipoprotein Separation by Rate-Zonal Ultracentrifugation.

Science.gov (United States)

Peters, Carl N; Evans, Iain E J

2016-12-01

Plasma lipoproteins are the primary means of lipid transport among tissues. Defining alterations in lipid metabolism is critical to our understanding of disease processes. However, lipoprotein measurement is limited to specialized centers. Preparation for ultracentrifugation involves the formation of complex density gradients that is both laborious and subject to handling errors. We created a fully automated device capable of forming the required gradient. The design has been made freely available for download by the authors. It is inexpensive relative to commercial density gradient formers, which generally create linear gradients unsuitable for rate-zonal ultracentrifugation. The design can easily be modified to suit user requirements and any potential future improvements. Evaluation of the device showed reliable peristaltic pump accuracy and precision for fluid delivery. We also demonstrate accurate fluid layering with reduced mixing at the gradient layers when compared to usual practice by experienced laboratory personnel. Reduction in layer mixing is of critical importance, as it is crucial for reliable lipoprotein separation. The automated device significantly reduces laboratory staff input and reduces the likelihood of error. Overall, this device creates a simple and effective solution to formation of complex density gradients. © 2015 Society for Laboratory Automation and Screening.

Long term effects on human plasma lipoproteins of a formulation enriched in butter milk polar lipid

Directory of Open Access Journals (Sweden)

Nilsson Åke

2009-10-01

Full Text Available Abstract Background Sphingolipids (SL, in particular sphingomyelin (SM are important components of milk fat polar lipids. Dietary SM inhibits cholesterol absorption in rats (Nyberg et al. J Nutr Biochem. 2000 and SLs decrease both cholesterol and TG concentrations in lipid- and cholesterol fed APOE*3Leiden mice (Duivenvoorden et al. Am J Clin Nutr. 2006. This human study examines effects of a butter milk formulation enriched in milk fat globule membrane material, and thereby in SLs, on blood lipids in healthy volunteers. In a four week parallel group study with 33 men and 15 women we examined the effects of an SL-enriched butter milk formulation (A and an equivalent control formulation (B on plasma lipid levels. Plasma concentrations of HDL and LDL cholesterol, triacylglycerols (TG, apolipoproteins AI and B, and lipoprotein (a were measured. The daily dose of SL in A was 975 mg of which 700 mg was SM. The participants registered food and drink intake four days before introducing the test formula and the last four days of the test period. Results A daily increase of SL intake did not significantly influence fasting plasma lipids or lipoproteins. In group B TG, cholesterol, LDL, HDL and apolipoprotein B concentrations increased, however, but not in group A after four weeks. The difference in LDL cholesterol was seen primarily in women and difference in TG primarily in men. No significant side effects were observed. Conclusion The study did not show any significant decrease on plasma lipids or lipoprotein levels of an SL-enriched formulation containing 2-3 times more SL than the normal dietary intake on cholesterol, other plasma lipids or on energy intake. The formulation A may, however, have counteracted the trend towards increased blood lipid concentrations caused by increased energy intake that was seen with the B formulation.

Effect of dietary carbohydrates on plasma lipoproteins in Sprague-Dawley and LA/N-corpulent rats

International Nuclear Information System (INIS)

Ellwood, K.C.

1989-01-01

Male Sprague-Dawley rats were fed diets containing 54% carbohydrate as either sucrose (S), fructose (F) or cooked cornstarch (CS) for 5 weeks. Plasma lipoproteins (LP) were isolated by density gradient ultracentrifugation and separated into very low density P (VLDL), low density LP (LDL) and high density LP (HDL) by gel filtration and affinity chromatography. ApoLP E-rich (R 1 and R 2 ) and apoLP E-poor subfractions (NR) of HDL were prepared by heparin-sepharose affinity chromatography. Rats were injected intraperitoneally with 3 H-leucine and sacrificed 2 hours later. Plasma lipoproteins were isolated as described above. The level of 3 H-protein in plasma was greater in Sprague-Dawley rats fed F than those fed S or CS. The amount of 3 H-protein in the chylomicron + VLDL fraction was affected by type of dietary carbohydrate: S > F > CS. Similar studies were conducted with the carbohydrate-sensitive obese and lean LA/N-corpulent rats. Levels of HDL-protein were lower in LA/N-corpulent rats fed S or F than in those fed CS. 3 H-chylomicron + VLDL was higher in rats fed S or F than those fed CS. The concentration of 3 H-protein in plasma and chylomicron + VLDL was greater in obese rats than in lean

Genetic determinants of LDL, lipoprotein(a), triglyceride-rich lipoproteins and HDL: concordance and discordance with cardiovascular disease risk

DEFF Research Database (Denmark)

Nordestgaard, Børge G; Tybjærg-Hansen, Anne

2011-01-01

To evaluate whether new and known genetic determinants of plasma levels of LDL cholesterol, lipoprotein(a), triglyceride-rich lipoproteins, and HDL cholesterol associate with the risk of cardiovascular disease expected from the effect on lipoprotein levels. Concordance or discordance...... of such genetic determinants with cardiovascular disease risk will either favor or disfavor that these lipoproteins are causally related to cardiovascular disease....

Structure and motion of phospholipids in human plasma lipoproteins. A 31P NMR study

International Nuclear Information System (INIS)

Fenske, D.B.; Chana, R.S.; Parmar, Y.I.; Treleaven, W.D.; Cushley, R.J.

1990-01-01

The structure and motion of phospholipids in human plasma lipoproteins have been studied by using 31 P NMR. Lateral diffusion coefficients, D T , obtained from the viscosity dependence of the 31 P NMR line widths, were obtained for very low density lipoprotein (VLDL), low-density lipoprotein (LDL), high-density lipoproteins (HDL 2 , HDL 3 ), and egg PC/TO microemulsions at 25 degree C, for VLDL at 40 degree C, and for LDL at 45 degree C. In order to prove the orientation and/or order of the phospholipid head-group, estimates of the residual chemical shift anistropy, Δσ, have been obtained for all the lipoproteins and the microemulsions from the viscosity and field dependence for the 31 P NMR line widths. These results suggest differences in the orientation and/or ordering of the head-group in the HDLs. The dynamic behavior of the phosphate moiety in LDL and HDL 3 has been obtained from the temperature dependence of the 31 P spin-lattice relaxation rates. Values of the correlation time for phosphate group reorientation and the activation energy for the motion are nearly identical in LDL and HDL 3 and are similar to values obtained for phospholipid bilayers. This argues against long-lived protein-lipid interactions being the source of either the slow diffusion in LDL or the altered head-group orientation in the HDLs

Reversible flow of cholesteryl ester between high-density lipoproteins and triacylglycerol-rich particles is modulated by the fatty acid composition and concentration of triacylglycerols

Directory of Open Access Journals (Sweden)

E.C.R. Quintão

2010-12-01

Full Text Available We determined the influence of fasting (FAST and feeding (FED on cholesteryl ester (CE flow between high-density lipoproteins (HDL and plasma apoB-lipoprotein and triacylglycerol (TG-rich emulsions (EM prepared with TG-fatty acids (FAs. TG-FAs of varying chain lengths and degrees of unsaturation were tested in the presence of a plasma fraction at d > 1.21 g/mL as the source of CE transfer protein. The transfer of CE from HDL to FED was greater than to FAST TG-rich acceptor lipoproteins, 18% and 14%, respectively. However, percent CE transfer from HDL to apoB-containing lipoproteins was similar for FED and FAST HDL. The CE transfer from HDL to EM depended on the EM TG-FA chain length. Furthermore, the chain length of the monounsaturated TG-containing EM showed a significant positive correlation of the CE transfer from HDL to EM (r = 0.81, P < 0.0001 and a negative correlation from EM to HDL (r = -041, P = 0.0088. Regarding the degree of EM TG-FAs unsaturation, among EMs containing C18, the CE transfer was lower from HDL to C18:2 compared to C18:1 and C18:3, 17.7%, 20.7%, and 20%, respectively. However, the CE transfer from EMs to HDL was higher to C18:2 than to C18:1 and C18:3, 83.7%, 51.2%, and 46.3%, respectively. Thus, the EM FA composition was found to be the rate-limiting factor regulating the transfer of CE from HDL. Consequently, the net transfer of CE between HDL and TG-rich particles depends on the specific arrangement of the TG acyl chains in the lipoprotein particle core.

[Plasma lipoproteins as drug carriers. Effect of phospholipid formulations].

Science.gov (United States)

Torkhovskaia, T I; Ipatova, O M; Medvedeva, N V; Ivanov, V S; Ivanova, L I

2010-01-01

The extensive development of nanotechnologies in the last two decades has brought about new understanding of plasma lipoproteins (LP) as natural drug nanocarriers that escape interaction with immune and reticuloendothelial systems. Drugs bound to LP (especially LDL) can more actively penetrate into cells of many cancer and inflammation tissues with enhanced expression or/and dysregulation of B,E receptors or possibly scavenger SR-BI receptors. Relevant studies are focused on the development of new dosage forms by conjugating lipophilic drugs either with isolated plasma LP or with their model formulations, such as nanoemulsions, mimetics, lipid nanospheres, etc. Some authors include in these particles serum or recombinant apoproteins, peptides, and modified polymer products. As shown recently, protein-free lipid nanoemulsions in plasma take up free apoA and apoE. Complexes with various LP also form after direct administration of lypophilic drugs into blood especially those enclosed in phospholipid formulations, e.g. liposomes. Results of evaluation of some lipophilic dugs (mainly cytostatics, amphotericin B, cyclosporine A, etc.) are discussed. Original data are presented on the influence of phospholipid formulations on the distribution of doxorubicin and indomethacin between LP classes after in vitro incubation in plasma. On the whole, the review illustrates the importance of research on LP and phospholi pid forms as drug nanocarriers to be used to enhance effect of therapy.

Effects of short-term niacin treatment on plasma lipoprotein concentrations in African green monkeys (Chlorocebus aethiops)

KAUST Repository

Chauke, Chesa G.; Arieff, Zainunisha; Kaur, Mandeep; Seier, Jü rgen V.

2014-01-01

Niacin is the most effective drug available for raising levels of high-density lipoprotein (HDL) cholesterol. To evaluate its effects on plasma lipid concentrations, the authors administered a low dose of niacin to healthy, adult, female African

Purification of a sarcoplasmic reticulum protein that binds Ca2+ and plasma lipoproteins

International Nuclear Information System (INIS)

Hofmann, S.L.; Brown, M.S.; Lee, E.; Pathak, R.K.; Anderson, R.G.; Goldstein, J.L.

1989-01-01

A protein in the sarcoplasmic reticulum of rabbit skeletal and cardiac muscle was identified because of its ability to bind 125I-labeled low density lipoprotein (LDL) with high affinity after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This protein, referred to as the 165-kDa protein, is restricted to striated muscle. It was not detected in 14 other tissues, including several that contain smooth muscle, but it appears in rat L6 myoblasts when they differentiate into myocytes. Immunofluorescence and immunoelectron microscopic studies revealed that the protein is present throughout the sarcoplasmic reticulum and the terminal cisternae. It binds 45Ca2+ on nitrocellulose blots and stains metachromatically with Stains-all, a cationic dye that stains Ca2+-binding proteins. It does not appear to be a glycoprotein, and it appears slightly larger than the 160-kDa glycoprotein previously described in sarcoplasmic reticulum. The 165-kDa protein binds LDL, beta-migrating very low density lipoprotein, and a cholesterol-induced high density lipoprotein particle that contains apoprotein E as its sole apoprotein with much higher affinity than it binds high density lipoprotein. The protein is stable to boiling and to treatment with sodium dodecyl sulfate, but it becomes sensitive to these treatments when its cystine residues are reduced and alkylated. The protein was purified 1300-fold to apparent homogeneity from rabbit skeletal muscle membranes. It differs from the cell surface LDL receptor in that (1) its apparent molecular weight is not changed by reduction and alkylation; (2) it is present in Watanabe-heritable hyperlipidemic rabbits, which lack functional LDL receptors; (3) binding of lipoproteins is not inhibited by EDTA; and (4) it is located within the lumen of the sarcoplasmic reticulum where it has no access to plasma lipoproteins

Lipophilic antioxidants and polyunsaturated fatty acids in lipoprotein classes: distribution and interaction

DEFF Research Database (Denmark)

Sunesen, V.H.; Weber, Christine; Hølmer, Gunhild Kofoed

2001-01-01

supplementations, but fish oil increased the amount of n-3 fatty acids at the expense of n-6 fatty acids. Conclusion: Lipoprotein distribution of CoQ(10) is markedly different from that of alpha -tocopherol, suggesting that they may be metabolised by distinct routes. alpha -Tocopherol is distributed similarly to n......Objective: To study the lipoprotein distribution of supplemented coenzyme Q(10) (CoQ(10)), vitamin E, and polyunsaturated fatty acids (PUFA). Design: Balanced three- period crossover study. Setting: University research unit. Subjects: Eighteen apparently healthy free-living non-smoking volunteers...... the first period and then after each period. Plasma and isolated lipoproteins were analysed for cholesterol, triacylglycerol, alpha- and gamma -tocopherol, CoQ(10), and fatty acid composition. Results: Significant (P

Effects of short-term niacin treatment on plasma lipoprotein concentrations in African green monkeys (Chlorocebus aethiops).

Science.gov (United States)

Chauke, Chesa G; Arieff, Zainunisha; Kaur, Mandeep; Seier, Jurgen V

2014-02-01

Niacin is the most effective drug available for raising levels of high-density lipoprotein (HDL) cholesterol. To evaluate its effects on plasma lipid concentrations, the authors administered a low dose of niacin to healthy, adult, female African green monkeys for 3 months. In the treated monkeys, low-density lipoprotein cholesterol concentrations decreased by 43% from baseline, whereas concentrations of HDL cholesterol and apolipoprotein A-I increased by 49% and 34%, respectively. The results suggest that in this primate model, a low dose of niacin can effectively increase concentrations of HDL cholesterol.

Activated platelets contribute to oxidized low-density lipoproteins and dysfunctional high-density lipoproteins through a phospholipase A2-dependent mechanism

NARCIS (Netherlands)

Blache, Denis; Gautier, Thomas; Tietge, Uwe J. F.; Lagrost, Laurent

Plasma activity of secretory phospholipase A2 (sPLA2) increases in patients with cardiovascular disease. The present study investigated whether platelet-released sPLA2 induces low-density lipoprotein (LDL) and high-density lipoprotein (HDL) modifications that translate into changes in lipoprotein

Triglycerides, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol in rats exposed to premium motor spirit fumes.

Science.gov (United States)

Aberare, Ogbevire L; Okuonghae, Patrick; Mukoro, Nathaniel; Dirisu, John O; Osazuwa, Favour; Odigie, Elvis; Omoregie, Richard

2011-06-01

Deliberate and regular exposure to premium motor spirit fumes is common and could be a risk factor for liver disease in those who are occupationally exposed. A possible association between premium motor spirit fumes and plasma levels of triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol using a rodent model could provide new insights in the pathology of diseases where cellular dysfunction is an established risk factor. The aim of this study was to evaluate the possible effect of premium motor spirit fumes on lipids and lipoproteins in workers occupationally exposed to premium motor spirit fumes using rodent model. Twenty-five Wister albino rats (of both sexes) were used for this study between the 4(th) of August and 7(th) of September, 2010. The rats were divided into five groups of five rats each. Group 1 rats were not exposed to premium motor spirit fumes (control group), group 2 rats were exposed for 1 hour daily, group 3 for 3 hours daily, group 4 for 5 hours daily and group 5 for 7 hours daily. The experiment lasted for a period of 4 weeks. Blood samples obtained from all the groups after 4 weeks of exposure were used for the estimation of plasma levels of triglyceride, total cholesterol, high density lipoprotein- cholesterol and low density lipoprotein- cholesterol. Results showed significant increase in means of plasma total cholesterol and low density lipoprotein levels (P<0.05). The mean triglyceride and total body weight were significantly lower (P<0.05) in the exposed group when compared with the unexposed. The plasma level of high density lipoprotein, the ratio of low density lipoprotein to high density lipoprotein and the ratio of total cholesterol to high density lipoprotein did not differ significantly in exposed subjects when compared with the control group. These results showed that frequent exposure to petrol fumes may be highly deleterious to the liver cells.

The lipid- and lipoprotein- [LDL-Lp(a)] apheresis techniques. Updating.

Science.gov (United States)

Stefanutti, C; Morozzi, C; Perrone, G; Di Giacomo, S; Vivenzio, A; D'Alessandri, G

2012-01-01

Therapeutic plasmapheresis allows the extracorporeal removal of plasmatic lipoproteins (Lipid-apheresis) (LA). It can be non selective (non specific), semi - selective or selective low density lipoprotein-lipoprotein(a) (specific [LDL- Lp(a)] apheresis) (Lipoprotein apheresis, LDLa). The LDL removal rate is a perfect parameter to assess the system efficiency. Plasma-Exchange (PEX) cannot be considered either specific nor, selective. In PEX the whole blood is separated into plasma and its corpuscular components usually through centrifugation or rather filtration. The corpuscular components mixed with albumin solution plus saline (NaCl 0.9%) solution at 20%-25%, are then reinfused to the patient, to substitute the plasma formerly removed. PEX eliminates atherogenic lipoproteins, but also other essential plasma proteins, such as albumin, immunoglobulins, and hemocoagulatory mediators. Cascade filtration (CF) is a method based on plasma separation and removal of plasma proteins through double filtration. During the CF two hollow-fiber filters with pores of different diameter are used to eliminate the plasma components of different weight and molecular diameter. A CF system uses a first polypropylene filter with 0.55 µm diameter pores and a second one of diacetate of cellulose with 0.02 µm pores. The first filter separates the whole blood, and the plasma is then perfused through a second filter which allows the recovery of molecules with a diameter lower than 0.02 µm, and the removal of molecules larger in diameter as apoB100-containing lipoproteins. Since both albumin and immunoglobulins are not removed, or to a negligible extent, plasma-expanders, substitution fluids, and in particular albumin, as occurs in PEX are not needed. CF however, is characterized by lower selectivity since removes also high density lipoprotein (HDL) particles which have an antiatherogenic activity. In the 80's, a variation of Lipid-apheresis has been developed which allows the LDL

21 CFR 862.1475 - Lipoprotein test system.

Science.gov (United States)

2010-04-01

... measure lipoprotein in serum and plasma. Lipoprotein measurements are used in the diagnosis and treatment of lipid disorders (such as diabetes mellitus), atherosclerosis, and various liver and renal diseases...

Systemic excretion of benzo(a)pyrene in the control and microsomally induced rat: the influence of plasma lipoproteins and albumin as carrier molecules

International Nuclear Information System (INIS)

Shu, H.P.; Bymun, E.N.

1983-01-01

In vitro studies have previously indicated that benzo(a)pyrene distributes primarily into the plasma lipoprotein fraction when incubated with whole plasma. Hydroxylated metabolites of benzo(a)pyrene distribute increasingly into the albumin fraction as the degree of metabolite hydroxylation increases. This report assesses the influence of plasma lipoproteins and albumin as carriers for benzo(a)pyrene on carcinogen excretion in the control and microsomally induced rat. Male Sprague-Dawley rats cannulated in the bile duct received i.v. injections of radiolabeled benzo(a)pyrene noncovalently bound to the very-low-density, low-density, or high-density lipoproteins in equimolar amounts. Bile was collected and measured for radioactivity. Cumulative biliary excretions of benzo(a)pyrene complexed with rat lipoproteins were 39.6 +/- 9.7 (S.D.), 24.6 +/- 1.3, and 21.2 +/- 8.8% for very low-density, low-density, and high-density lipoprotein, respectively. Values for excretion of benzo(a)pyrene complexed with rat or human lipoproteins were comparable. These data suggest that the transport molecule can effect a 2-fold difference in benzo(a)pyrene excretion under conditions of the present study. Thus, excretion increased as the degree of benzo(a)pyrene hydroxylation increased. The effect of microsomal enzyme induction on excretion of lipoprotein-bound benzo(a)pyrene was also assessed. Contrary to expectation, excretion of benzo(a)pyrene bound to the very-low-density, low-density, or high-density lipoproteins in Aroclor-induced rats was not greater than that of control animals. Hence, under the conditions of the present study, 60 to 80% of the injected benzo(a)pyrene and 50 to 60% of the injected benzo(a)pyrene metabolites were not excreted immediately in control or microsomally induced animals. This benzo(a)pyrene may represent a carcinogen pool that is slowly excreted

Effects of short-term niacin treatment on plasma lipoprotein concentrations in African green monkeys (Chlorocebus aethiops)

KAUST Repository

Chauke, Chesa G.

2014-01-22

Niacin is the most effective drug available for raising levels of high-density lipoprotein (HDL) cholesterol. To evaluate its effects on plasma lipid concentrations, the authors administered a low dose of niacin to healthy, adult, female African green monkeys for 3 months. In the treated monkeys, low-density lipoprotein cholesterol concentrations decreased by 43% from baseline, whereas concentrations of HDL cholesterol and apolipoprotein A-I increased by 49% and 34%, respectively. The results suggest that in this primate model, a low dose of niacin can effectively increase concentrations of HDL cholesterol.©2014 Nature America, Inc. All rights reserved.

Serum Paraoxonase 1 Activity Is Associated with Fatty Acid Composition of High Density Lipoprotein

Directory of Open Access Journals (Sweden)

Maryam Boshtam

2013-01-01

Full Text Available Introduction. Cardioprotective effect of high density lipoprotein (HDL is, in part, dependent on its related enzyme, paraoxonase 1 (PON1. Fatty acid composition of HDL could affect its size and structure. On the other hand, PON1 activity is directly related to the structure of HDL. This study was designed to investigate the association between serum PON1 activity and fatty acid composition of HDL in healthy men. Methods. One hundred and forty healthy men participated in this research. HDL was separated by sequential ultracentrifugation, and its fatty acid composition was analyzed by gas chromatography. PON1 activity was measured spectrophotometrically using paraxon as substrate. Results. Serum PON1 activity was directly correlated with the amount of stearic acid and dihomo-gamma-linolenic acid (DGLA. PON1/HDL-C was directly correlated with the amount of miristic acid, stearic acid, and DGLA and was inversely correlated with total amount of ω6 fatty acids of HDL. Conclusion. The fatty acid composition of HDL could affect the activity of its associated enzyme, PON1. As dietary fats are the major determinants of serum lipids and lipoprotein composition, consuming some special dietary fatty acids may improve the activity of PON1 and thereby have beneficial effects on health.

Serum paraoxonase 1 activity is associated with fatty acid composition of high density lipoprotein.

Science.gov (United States)

Boshtam, Maryam; Razavi, Amirnader Emami; Pourfarzam, Morteza; Ani, Mohsen; Naderi, Gholam Ali; Basati, Gholam; Mansourian, Marjan; Dinani, Narges Jafari; Asgary, Seddigheh; Abdi, Soheila

2013-01-01

Cardioprotective effect of high density lipoprotein (HDL) is, in part, dependent on its related enzyme, paraoxonase 1 (PON1). Fatty acid composition of HDL could affect its size and structure. On the other hand, PON1 activity is directly related to the structure of HDL. This study was designed to investigate the association between serum PON1 activity and fatty acid composition of HDL in healthy men. One hundred and forty healthy men participated in this research. HDL was separated by sequential ultracentrifugation, and its fatty acid composition was analyzed by gas chromatography. PON1 activity was measured spectrophotometrically using paraxon as substrate. Serum PON1 activity was directly correlated with the amount of stearic acid and dihomo-gamma-linolenic acid (DGLA). PON1/HDL-C was directly correlated with the amount of miristic acid, stearic acid, and DGLA and was inversely correlated with total amount of ω 6 fatty acids of HDL. The fatty acid composition of HDL could affect the activity of its associated enzyme, PON1. As dietary fats are the major determinants of serum lipids and lipoprotein composition, consuming some special dietary fatty acids may improve the activity of PON1 and thereby have beneficial effects on health.

Effect of dietary vegetable oils on the fatty acid profile of plasma lipoproteins in dairy cows

DEFF Research Database (Denmark)

Vargas-Bello-Pérez, Einar; Íñiguez-González, Gonzalo; Cancino-Padilla, Nathaly

2016-01-01

ABSTRACT: The aim of this study was to elucidate the effect of dietary supplementation of soybean oil (SO) and hydrogenated palm oil (HPO) on the transport of fatty acids (FA) within plasma lipoproteins in lactating and non-lactating cows. Three lactating and three non-lactating Holstein cows were...

What are lipoproteins doing in the brain?

Science.gov (United States)

Wang, Hong; Eckel, Robert H

2014-01-01

Lipoproteins in plasma transport lipids between tissues, however, only high-density lipoproteins (HDL) appear to traverse the blood-brain barrier (BBB); thus, lipoproteins found in the brain must be produced within the central nervous system. Apolipoproteins E (ApoE) and ApoJ are the most abundant apolipoproteins in the brain, are mostly synthesized by astrocytes, and are found on HDL. In the hippocampus and other brain regions, lipoproteins help to regulate neurobehavioral functions by processes that are lipoprotein receptor-mediated. Moreover, lipoproteins and their receptors also have roles in the regulation of body weight and energy balance, acting through lipoprotein lipase (LPL) and the low-density lipoprotein (LDL) receptor-related protein (LRP). Thus, understanding lipoproteins and their metabolism in the brain provides a new opportunity with potential therapeutic relevance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Peroxisome Proliferator Activated Receptors and Lipoprotein Metabolism

NARCIS (Netherlands)

Kersten, A.H.

2008-01-01

Plasma lipoproteins are responsible for carrying triglycerides and cholesterol in the blood and ensuring their delivery to target organs. Regulation of lipoprotein metabolism takes place at numerous levels including via changes in gene transcription. An important group of transcription factors that

Immunosuppressive activity of human cord-blood lipoproteins

International Nuclear Information System (INIS)

Forte, T.M.; Davis, P.A.; Curtiss, L.K.

1985-01-01

It is now known that the role of plasma lipoproteins is multifunctional. More recently it has been shown that lipoproteins may regulate immune responses as well. Low-density lipoproteins carrying apolipoprotein B (apoB) are known to suppress phytohemagglutinin (PHA) activated lymphocytes by inhibiting DNA synthesis. More recently, an immunoregulatory role has been described for another apolipoprotein, apoE, which is found in low quantities in normal plasma. In these studies with human umbilical-cord blood the authors were intrigued by two factors: the low level of LDL and hence apoB, and the elevated quantity of apoE. This study examines the hypothesis that apoE may regulate lymphocyte function in the human fetus

Decrease in plasma high-density lipoprotein cholesterol levels at puberty in boys with delayed adolescence: correlation with plasma testosterone levels

International Nuclear Information System (INIS)

Kirkland, R.T.; Keenan, B.S.; Probstfield, J.L.; Patsch, W.; Lin, T.L.; Clayton, G.W.; Insull, W. Jr.

1987-01-01

A three-phase study tested the hypothesis that the decrease in the high-density lipoprotein cholesterol (HDL-C) level observed in boys at puberty is related to an increase in the plasma testosterone concentration. In phase I, 57 boys aged 10 to 17 years were categorized into four pubertal stages based on clinical parameters and plasma testosterone levels. These four groups showed increasing plasma testosterone values and decreasing HDL-C levels. In phase II, 14 boys with delayed adolescence were treated with testosterone enanthate. Plasma testosterone levels during therapy were in the adult male range. Levels of HDL-C decreased by a mean of 7.4 mg/dL (0.20 mmol/L) and 13.7 mg/dL (0.35 mmol/L), respectively, after the first two doses. In phase III, 13 boys with delayed adolescence demonstrated increasing plasma testosterone levels and decreasing HDL-C levels during spontaneous puberty. Levels of HDL-C and apolipoprotein A-1 were correlated during induced and spontaneous puberty. Testosterone should be considered a significant determinant of plasma HDL-C levels during pubertal development

Liver lipase and high-density lipoprotein. Lipoprotein changes after incubation of human serum with rat liver lipase.

Science.gov (United States)

Groot, P H; Scheek, L M; Jansen, H

1983-05-16

Human sera were incubated with rat liver lipase after inactivation of lecithin:cholesterol acyltransferase, and the changes in serum lipoprotein composition were measured. In the presence of liver lipase serum triacylglycerol and phosphatidylcholine were hydrolyzed. The main changes in the concentrations of these lipids were found in the high-density lipoprotein fraction. Subfractionation of high-density lipoprotein by rate-zonal ultracentrifugation showed a prominent decrease in all constituents of high-density lipoprotein2, a smaller decrease in the 'light' high-density lipoprotein3 and an increase in the 'heavy' high-density lipoprotein3. These data support a concept in which liver lipase is involved in high-density lipoprotein2 phospholipid and triacylglycerol catabolism and suggest that as a result of this action high-density lipoprotein2 is converted into high-density lipoprotein3.

Mechanism of action of gemfibrozil on lipoprotein metabolism.

OpenAIRE

Saku, K; Gartside, P S; Hynd, B A; Kashyap, M L

1985-01-01

Gemfibrozil is a potent lipid regulating drug whose major effects are to increase plasma high density lipoproteins (HDL) and to decrease plasma triglycerides (TG) in a wide variety of primary and secondary dyslipoproteinemias. Its mechanism of action is not clear. Six patients with primary familial endogenous hypertriglyceridemia with fasting chylomicronemia (type V lipoprotein phenotype) with concurrent subnormal HDL cholesterol levels (HDL deficiency) were treated initially by diet and once...

Low-density Lipoprotein Improves Motility and Plasma Membrane Integrity of Cryopreserved Canine Epididymal Spermatozoa.

Science.gov (United States)

Prapaiwan, N; Tharasanit, T; Punjachaipornpol, S; Yamtang, D; Roongsitthichai, A; Moonarmart, W; Kaeoket, K; Manee-In, S

2016-05-01

Cryopreservation of caudal epididymal spermatozoa is an effective technique to conserve genetic potentials of superior dogs when it is not possible to collect ejaculated spermatozoa. Although hen egg yolk is commonly supplemented into the semen extender, active substances within the egg yolk which protect sperm against cryoinjury remain to be discovered. Among its compositions, low-density lipoprotein (LDL) has been reported to have a cryoprotective property for sperm cryopreservation. However, the effects of LDL on dog epididymal spermatozoa during cryopreservation have not yet been investigated. This study aimed to investigate the effects of LDL on epididymal spermatozoa quality following cryopreservation and thawing. After routine castration of 12 dogs, caudal epididymides from individuals were separated from the testes and cut into a few pieces in a Tris-buffer. Spermatozoa recovered from each sample were examined at once for sperm quality and divided into six groups of extender: no LDL, 20% egg yolk, 4%, 8%, 16%, and 24% LDL, before cryopreservation. The sperm aliquots were then equilibrated and conventionally frozen. After thawing, sperm motility, morphology, plasma membrane integrity, and acrosome integrity were evaluated. The results revealed that 4% LDL and 20% egg yolk yielded significantly higher sperm motility (57.69% and 52.69%, respectively, p<0.05) than other LDLs. In addition, 4% LDL yielded the significantly highest plasma membrane integrity (70.54%, p<0.05). In conclusion, the supplementation of 4% LDL in Tris-glucose extender could be applied for cryopreservation of canine epididymal spermatozoa.

Low-density Lipoprotein Improves Motility and Plasma Membrane Integrity of Cryopreserved Canine Epididymal Spermatozoa

Directory of Open Access Journals (Sweden)

N. Prapaiwan

2016-05-01

Full Text Available Cryopreservation of caudal epididymal spermatozoa is an effective technique to conserve genetic potentials of superior dogs when it is not possible to collect ejaculated spermatozoa. Although hen egg yolk is commonly supplemented into the semen extender, active substances within the egg yolk which protect sperm against cryoinjury remain to be discovered. Among its compositions, low-density lipoprotein (LDL has been reported to have a cryoprotective property for sperm cryopreservation. However, the effects of LDL on dog epididymal spermatozoa during cryopreservation have not yet been investigated. This study aimed to investigate the effects of LDL on epididymal spermatozoa quality following cryopreservation and thawing. After routine castration of 12 dogs, caudal epididymides from individuals were separated from the testes and cut into a few pieces in a Tris-buffer. Spermatozoa recovered from each sample were examined at once for sperm quality and divided into six groups of extender: no LDL, 20% egg yolk, 4%, 8%, 16%, and 24% LDL, before cryopreservation. The sperm aliquots were then equilibrated and conventionally frozen. After thawing, sperm motility, morphology, plasma membrane integrity, and acrosome integrity were evaluated. The results revealed that 4% LDL and 20% egg yolk yielded significantly higher sperm motility (57.69% and 52.69%, respectively, p<0.05 than other LDLs. In addition, 4% LDL yielded the significantly highest plasma membrane integrity (70.54%, p<0.05. In conclusion, the supplementation of 4% LDL in Tris-glucose extender could be applied for cryopreservation of canine epididymal spermatozoa.

Characteristics of 2,4,5,2',4',5'-hexachlorobiphenyl distribution among lipoproteins in vitro

International Nuclear Information System (INIS)

Vomachka, M.S.; Vodicnik, M.J.; Lech, J.J.

1983-01-01

The uptake, distribution, and transfer of 2,4,5,2',4',5'-hexachlorobiphenyl (6-CB) were examined in vitro with human and rat whole blood, plasma, and lipoprotein fractions. 6-CB distribution between plasma and erythrocytes as well as among lipoproteins was determined following sedimentation of erythrocytes and ultracentrifugal fractionation of plasma. In both rat and human whole blood, 70 to 75% of 6-CB partitioned into plasma and 25 to 30% into erythrocytes. The uptake of 6-CB into plasma was extremely rapid and the rate of uptake was found to be dependent upon temperature. The distribution of 6-CB among lipoproteins was relatively homogeneous with 20 to 30% being distributed in very low-density lipoproteins (VLDL, d . 0.95-1.006 g/ml), 15 to 20% in low-density lipoproteins (LDL, d . 1.006-1.063 g/ml), and 15 to 25% in high-density lipoproteins (HDL, d . 1.063-1.21 g/ml). Over 25% of 6-CB was found in the remaining bottom fraction. In addition, each isolated fraction when incubated alone with 6-CB was shown capable of uptake. The relative proportion of 6-CB among the lipoproteins was independent of the level taken up by plasma. 6-CB was also found to transfer among lipoproteins. This exchange of 6-CB proved to be dependent upon the concentrations of both protein and triacylglycerol in the incubations. Two proteins in the bottom fraction (Bf), albumin and a steroid binding globulin, were capable of competing with the lipoproteins for 6-CB uptake

Chronic Exercise Reduces CETP and Mesterolone Treatment Counteracts Exercise Benefits on Plasma Lipoproteins Profile: Studies in Transgenic Mice.

Science.gov (United States)

Casquero, Andrea Camargo; Berti, Jairo Augusto; Teixeira, Laura Lauand Sampaio; de Oliveira, Helena Coutinho Franco

2017-12-01

Regular exercise and anabolic androgenic steroids have opposing effects on the plasma lipoprotein profile and risk of cardio-metabolic diseases in humans. Studies in humans and animal models show conflicting results. Here, we used a mice model genetically modified to mimic human lipoprotein profile and metabolism. They under-express the endogenous LDL receptor gene (R1) and express a human transgene encoding the cholesteryl ester transfer protein (CETP), normally absent in mice. The present study was designed to evaluate the independent and interactive effects of testosterone supplementation, exercise training and CETP expression on the plasma lipoprotein profile and CETP activity. CETP/R1 and R1 mice were submitted to a 6-week swimming training and mesterolone (MEST) supplementation in the last 3 weeks. MEST treatment increased markedly LDL levels (40%) in sedentary CETP/R1 mice and reduced HDL levels in exercised R1 mice (18%). A multifactorial ANOVA revealed the independent effects of each factor, as follows. CETP expression reduced HDL (21%) and increased non-HDL (15%) fractions. MEST treatment increased the VLDL concentrations (42%) regardless of other interventions. Exercise training reduced triacylglycerol (25%) and free fatty acids (20%), increased both LDL and HDL (25-33%), and reduced CETP (19%) plasma levels. Significant factor interactions showed that the increase in HDL induced by exercise is explained by reducing CETP activity and that MEST blunted the exercise-induced elevation of HDL-cholesterol. These results reinforce the positive metabolic effects of exercise, resolved a controversy about CETP response to exercise and evidenced MEST potency to counteract specific exercise benefits.

Flow-mediated lipoprotein retention; Pregnancy-associated plasma protein-A inhibition in atherosclerosis and its release during myocardial ischemia

DEFF Research Database (Denmark)

Steffensen, Lasse Bach

, which states that retention of lipoproteins is the key initiating event of atherosclerosis development. Pregnancy-associated plasma protein-A (PAPP-A) regulates the insulin-like growth factor (IGF) system by proteolytic cleavage of a subset of IGF-binding proteins. Studies in mice have established PAPP...

PCSK9 and triglyceride-rich lipoprotein metabolism.

Science.gov (United States)

Druce, I; Abujrad, H; Ooi, T C

2015-07-20

Pro-protein convertase subtilisin-kexin 9 (PCSK9) is known to affect low-density lipoprotein (LDL) metabolism, but there are indications from several lines of research that it may also influence the metabolism of other lipoproteins, especially triglyceride-rich lipoproteins (TRL). This review summarizes the current data on this possible role of PCSK9. A link between PCSK9 and TRL has been suggested through the demonstration of (1) a correlation between plasma PCSK9 and triglyceride (TG) levels in health and disease, (2) a correlation between plasma PCSK9 and markers of carbohydrate metabolism, which is closely related to TG metabolism, (3) an effect of TG-lowering fibrate therapy on plasma PCSK9 levels, (4) an effect of PCSK9 on postprandial lipemia, (5) an effect of PCSK9 on adipose tissue biology, (6) an effect of PCSK9 on apolipoprotein B production from the liver and intestines, (7) an effect of PCSK9 on receptors other than low density lipoprotein receptor (LDLR) that are involved in TRL metabolism, and (8) an effect of anti-PCSK9 therapy on serum TG levels. The underlying mechanisms are unclear but starting to emerge. © 2015 the Journal of Biomedical Research. All rights reserved.

Changes in lipoprotein kinetics associated with type 2 diabetes affect the distribution of lipopolysaccharides among lipoproteins.

Science.gov (United States)

Vergès, Bruno; Duvillard, Laurence; Lagrost, Laurent; Vachoux, Christelle; Garret, Céline; Bouyer, Karine; Courtney, Michael; Pomié, Céline; Burcelin, Rémy

2014-07-01

Lipopolysaccharides (LPSs) are inflammatory components of the outer membrane of Gram-negative bacteria and, in plasma, are mostly associated with lipoproteins. This association is thought to promote their catabolism while reducing their proinflammatory effects. Our aim was to determine the impact of lipoprotein kinetics on plasma LPS distribution and how it may affect patients with type 2 diabetes mellitus (T2DM). We performed a kinetic study in 30 individuals (16 T2DM patients, 14 controls) and analyzed the impact of changes in lipoprotein kinetics on LPS distribution among lipoproteins. Plasma LPS levels in T2DM patients were not different from those in controls, but LPS distribution in the two groups was different. Patients with T2DM had higher LPS-very low-density lipoprotein (VLDL; 31% ± 7% vs 22% ± 11%, P = .002), LPS-high-density lipoprotein (HDL; 29% ± 9% vs 19% ± 10%, P = .015), free (nonlipoprotein bound) LPS (10% ± 4% vs 7% ± 4%, P = .043) and lower LPS-low-density lipoprotein (LDL; 30% ± 13% vs 52% ± 16%, P = .001). In multivariable analysis, VLDL-LPS was associated with HDL-LPS (P < .0001); LDL-LPS was associated with VLDL-LPS (P = .004), and VLDL apolipoprotein (apo) B100 catabolism (P = .002); HDL-LPS was associated with free LPS (P < .0001) and VLDL-LPS (P = .033); free LPS was associated with HDL-LPS (P < .0001). In a patient featuring a dramatic decrease in VLDL catabolism due to apoA-V mutation, LDL-LPS was severely decreased (0.044 EU/mL vs 0.788 EU/mL in controls). The difference between T2DM patients and controls for LDL-LPS fraction was no longer significant after controlling for VLDL apoB100 total fractional catabolic rate. Our data suggest that in humans, free LPS transfers first to HDL and then to VLDL, whereas the LPS-bound LDL fraction is mainly derived from VLDL catabolism; the latter may hence represent a LPS catabolic pathway. T2DM patients show lower LDL-LPS secondary to reduced VLDL catabolism, which may represent an

Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

Directory of Open Access Journals (Sweden)

Cornish Marion L

2007-12-01

Full Text Available Abstract Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in

Experimental hypothyroidism modulates the expression of the low density lipoprotein receptor by the liver

International Nuclear Information System (INIS)

Scarabottolo, Lia; Trezzi, Ermanno; Roma, Paola; Catapano, A.L.

1986-01-01

The effect of exprimental hypothyroidism of the catabolism of plasma lipoproteins and on the expression of low density lipoprotein receptors by the liver was investigated in rats made hypothyroid by surgery. The animals developed mild hypercholesterolemia, mainly due to an increase of plasma low density lipoprotein, while other lipoprotein classes were only marginally affected. Kinetic studies using ( 125 I)LDL indicated that a decreased fractional catabolic rate of the lipoprotein was responsible for this finding in agreement with the in vitro observation of a reduced binding of lipoproteins to liver membranes from hyperthyroid rats and with the demonstrations, by ligand blotting analysis, of a decreasd expression of lipoprotein receptors in liver membranes. These data suggest that hypothyroidism affects lipoprotein distribution also by decreasing the catabolism of low density lipoproteins by the liver (author)

Opposing effects of apolipoprotein m on catabolism of apolipoprotein B-containing lipoproteins and atherosclerosis

DEFF Research Database (Denmark)

Christoffersen, Christina; Pedersen, Tanja Xenia; Gordts, Philip L S M

2010-01-01

Rationale: Plasma apolipoprotein (apo)M is mainly associated with high-density lipoprotein (HDL). HDL-bound apoM is antiatherogenic in vitro. However, plasma apoM is not associated with coronary heart disease in humans, perhaps because of a positive correlation with plasma low-density lipoprotein...

Early incorporation of cell-derived cholesterol into pre-beta-migrating high-density lipoprotein

International Nuclear Information System (INIS)

Castro, G.R.; Fielding, C.J.

1988-01-01

Cultures of human skin fibroblasts were labeled to high cholesterol specific activity with [ 3 H]cholesterol and incubated briefly (1-3 min) with normal human plasma. The plasma was fractionated by two-dimensional agarose-polyacrylamide gel electrophoresis and the early appearance of cholesterol label among plasma lipoproteins determined. A major part of the label at 1-min incubation was in a pre-beta-migrating apo A-I lipoprotein fraction with a molecular weight of ca. 70,000. Label was enriched about 30-fold in this fraction relative to its content of apo A-I (1-2% of total apo A-I). The proportion of label in this lipoprotein was strongly correlated with its concentration in plasma. Further incubation (2 min) in the presence of unlabeled cells demonstrated transfer of label from this fraction to a higher molecular weight pre-beta apo A-I species, to low-density lipoprotein, and to the alpha-migrating apo A-I that made up the bulk (96%) of total apo A-I in plasma. The data suggest that a significant part of cell-derived cholesterol is transferred specifically to a pre-beta-migrating lipoprotein A-I species as part of a cholesterol transport transfer sequence in plasma

Lipoprotein(a) as a cardiovascular risk factor: current status

DEFF Research Database (Denmark)

Nordestgaard, Børge G; Chapman, M John; Ray, Kausik

2010-01-01

The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies.......The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies....

Application of directly coupled HPLC MMR to separation and characterization of lipoproteins from human serum

DEFF Research Database (Denmark)

Daykin, C. A.; Corcoran, O.; Hansen, S. H.

2001-01-01

method for the separation of highdensity lipoprotein, low-density lipoprotein, and very low-density lipoprotein from intact serum or plasma. The separation was achieved using a hydroxyapatite column and elution with pH 7.4 phosphate buffer with 100-muL injections of whole plasma. Coelution of HDL...... run time was 90 min with stopped-now 600-MHz NMR spectra of each lipoprotein being collected using 128 scans, in 7 min. The H-1 NMR chemical shifts of lipid signals were identical to conventional NMR spectra of freshly prepared lipoprotein standards, confirming that the lipoproteins were not degraded...

Comparison of diet consumption, body composition and lipoprotein lipid values of Kuwaiti fencing players with international norms

Directory of Open Access Journals (Sweden)

Hajji Salman

2011-10-01

Full Text Available Abstract Background No published data is currently available that describes the dietary patterns or physiological profiles of athletes participating on the Kuwaiti national fencing team and its potential impact on health and physical performance. The purpose of this investigation was to: 1 collect baseline data on nutrient intake 2 collect, analyze and report baseline for body composition, plasma lipid and lipoprotein concentrations during the competitive season, 3 compare the results with the international norms, 4 and provide necessary health and nutritional information in order to enhance the athletes' performance and skills. Methods Fifteen national-class fencers 21.5 ± 2.6 years of age participated in this study. Food intake was measured using a 3-day food record. Body composition was estimated using both the BOD POD and Body Mass Index (BMI. Total blood lipid profiles and maximum oxygen consumption was measured for each of the subjects during the competitive season. Results The results of the present study showed significant differences in dietary consumption in comparison with the recommended dietary allowances (RDA. The blood lipids profile and body composition (BMI and % body fat were in normal range in comparison with international norms However, the average VO2 max value was less than the value of the other fencers. Conclusion Due to the results of the research study, a dietary regimen can be designed that would better enhance athletic performance and minimize any health risks associated with nutrition. Percent body fat and BMI will also be categorized for all players. In addition, the plasma blood tests will help to determine if any of the players have an excessive level of lipids or any blood abnormalities. The outcomes of present study will have a direct impact on the players health and therefore their skills and athletic performance.

Metabolism of cholesteryl esters of rat very low density lipoproteins.

Science.gov (United States)

Faergeman, O; Havel, R J

1975-06-01

Rat very low density lipoproteins (d smaller than 1.006), biologically labeled in esterified and free cholesterol, were obtained form serum 6 h after intravenous injection of particulate (3-H) cholesterol. When injected into recipient animals, the esterified cholesterol was cleared form plasma with a half-life of 5 min. After 15 min, 71% of the injected esterified (3-H) cholesterol had been taken up by the liver, where it was rapidly hydrolyzed. After 60 min only 3.3% of the amount injected had been transferred, via lipoproteins of intermediate density, to the low density lipoproteins of plasma (d 1.019-1.063). Both uptake in the liver and transfer to low density lipoproteins occurred without change of distribution of 3-H in the various cholesteryl esters. 3-H appearing in esterified cholesterol of high density lipoproteins (d greater than 1.063) was derived from esterification, presumably by lecithin: cholesterol acyltransferase, of simultaneously injected free (3-H) cholesterol. Content of free (3-H) cholesterol in the very low density lipoproteins used for injection could be reduced substantially by incubation with erythrocytes. This procedure, however, increased the rate of clearance of the lipoproteins after injection into recipient rats. These studies show that hepatic removal is the major catabolic pathway for cholesteryl esters of rat very low density lipoproteins and that transfer to low density lipoproteins occurs to only a minor extent.

Low-density Lipoprotein Improves Motility and Plasma Membrane Integrity of Cryopreserved Canine Epididymal Spermatozoa

OpenAIRE

N. Prapaiwan; T. Tharasanit; S. Punjachaipornpol; D. Yamtang; A. Roongsitthichai; W. Moonarmart; K. Kaeoket; S. Manee-in

2016-01-01

Cryopreservation of caudal epididymal spermatozoa is an effective technique to conserve genetic potentials of superior dogs when it is not possible to collect ejaculated spermatozoa. Although hen egg yolk is commonly supplemented into the semen extender, active substances within the egg yolk which protect sperm against cryoinjury remain to be discovered. Among its compositions, low-density lipoprotein (LDL) has been reported to have a cryoprotective property for sperm cryopreservation. Howeve...

A comparison of the effects of 2 doses of soy protein or casein on serum lipids, serum lipoproteins, and plasma total homocysteine in hypercholesterolemic subjects.

Science.gov (United States)

Tonstad, Serena; Smerud, Knut; Høie, Lars

2002-07-01

Studies have shown that soy protein reduces some atherogenic lipid and lipoprotein concentrations, although lipoprotein(a) concentrations may be increased. The dose response of soy protein has not been established; neither has its effect on plasma total homocysteine. Our objective was to evaluate the effect of 2 doses of soy protein on lipid, lipoprotein, and homocysteine concentrations. Four to 24 wk after being instructed to consume a lipid-lowering diet, 130 men and women with LDL-cholesterol concentrations > or = 4 mmol/L were studied during a parallel group trial in which 4 interventions were assigned randomly. Thirty grams isolated soy protein (ISP) and 10 g cotyledon fiber or 50 g ISP and 16.6 g cotyledon fiber or equivalent doses of casein and cellulose were consumed daily as a beverage for 16 wk. When the 2 groups who consumed ISP were compared with the 2 groups who consumed casein, the differences in the net changes from baseline to week 16 in the concentrations of LDL cholesterol and plasma total homocysteine were -0.26 mmol/L (95% CI: -0.43, -0.09 mmol/L; P = 0.01) and -0.8 micromol/L (-1.4, -0.2 micromol/L; P = 0.005), respectively. The effect of the ISP dose was not significant. There were no significant differences between the 2 ISP and the 2 casein groups in changes in lipoprotein(a), HDL-cholesterol, or triacylglycerol concentrations. Adding 30-50 g soy protein/d to a lipid-lowering diet significantly reduced LDL-cholesterol concentrations without increasing lipoprotein(a) concentrations. Plasma total homocysteine concentrations also decreased, suggesting a novel, possibly antiatherosclerotic effect.

PLTP activity in premenopausal women. Relationship with lipoprotein lipase, HDL, LDL, body fat, and insulin resistance.

Science.gov (United States)

Murdoch, S J; Carr, M C; Hokanson, J E; Brunzell, J D; Albers, J J

2000-02-01

Plasma phospholipid transfer protein (PLTP) is thought to play a major role in the facilitated transfer of phospholipids between lipoproteins and in the modulation of high density lipoprotein (HDL) particle size and composition. However, little has been reported concerning the relationships of PLTP with plasma lipoprotein parameters, lipolytic enzymes, body fat distribution, insulin, and glucose in normolipidemic individuals, particularly females. In the present study, 50 normolipidemic healthy premenopausal females were investigated. The relationships between the plasma PLTP activity and selected variables were assessed. PLTP activity was significantly and positively correlated with low density lipoprotein (LDL) cholesterol (r(s) = 0.53), apoB (r(s) = 0.44), glucose (r(s) = 0.40), HDL cholesterol (r(s) = 0.38), HDL(3) cholesterol (r(s) = 0.37), lipoprotein lipase activity (r(s) = 0.36), insulin (r(s) = 0.33), subcutaneous abdominal fat (r(s) = 0.36), intra-abdominal fat (r(s) = 0.29), and body mass index (r(s) = 0.29). HDL(2) cholesterol, triglyceride, and hepatic lipase were not significantly related to PLTP activity. As HDL(2) can be decreased by hepatic lipase and hepatic lipase is increased in obesity with increasing intra-abdominal fat, the participants were divided into sub-groups of non-obese (n = 35) and obese (n = 15) individuals and the correlation of PLTP with HDL(2) cholesterol was re-examined. In the non-obese subjects, HDL(2) cholesterol was found to be significantly and positively related to PLTP activity (r(s) = 0.44). Adjustment of the HDL(2) values for the effect of hepatic lipase activity resulted in a significant positive correlation between PLTP and HDL(2) (r(s) = 0.41), indicating that the strength of the relationship between PLTP activity and HDL(2) can be reduced by the opposing effect of hepatic lipase on HDL(2) concentrations. We conclude that PLTP-facilitated lipid transfer activity is related to HDL and LDL metabolism, as well as

High-density lipoproteins and adrenal steroidogenesis : A population-based study

NARCIS (Netherlands)

Buitenwerf, Edward; Kerstens, Michiel N.; Links, Thera P.; Kema, Ido P.; Dullaart, Robin P. F.

BACKGROUND: Cholesterol trafficked within plasma lipoproteins, in particular high-density lipoproteins (HDL), may represent an important source of cholesterol that is required for adrenal steroidogenesis. Based on a urinary gas chromatography method, compromised adrenal function has been suggested

Plasma levels of 27-hydroxycholesterol in humans and mice with monogenic disturbances of high density lipoprotein metabolism

DEFF Research Database (Denmark)

Karuna, Ratna; Holleboom, Adriaan G; Motazacker, Mohammad M

2011-01-01

Secretion of 27-hydroxycholesterol (27OHC) from macrophages is considered as an alternative to HDL-mediated reverse transport of excess cholesterol. We investigated 27OHC-concentrations in plasma of humans and mice with monogenic disorders of HDL metabolism. As compared to family controls mutations...... activities of LCAT and CETP, respectively, than the formation and transfer of cholesterylesters. 27OHC plasma levels were also decreased in apoA-I-, ABCA1- or LCAT-knockout mice but increased in SR-BI-knockout mice. Transplantation of ABCA1- and/or ABCG1-deficient bone marrow into LDL receptor deficient mice...... decreased plasma levels of 27OHC. In conclusion, mutations or absence of HDL genes lead to distinct alterations in the quantity, esterification or lipoprotein distribution of 27OHC. These findings argue against the earlier suggestion that 27OHC-metabolism in plasma occurs independently of HDL....

Effect of omega-3 fatty acid ethyl esters on the oxylipin composition of lipoproteins in hypertriglyceridemic, statin-treated subjects.

Science.gov (United States)

Newman, John W; Pedersen, Theresa L; Brandenburg, Verdayne R; Harris, William S; Shearer, Gregory C

2014-01-01

Oxylipins mediate inflammation, vascular tension, and more. Their presence in lipoproteins could explain why lipoproteins mediate nearly identical activities. To determine how oxylipins are distributed in the lipoproteins of hypertriglyceridemic subjects, and whether omega-3 fatty acids alter them in a manner consistent with improved cardiovascular health, we recruited 15 dyslipidemic subjects whose levels of low density lipoprotein cholesterol (LDL-C) were at goal but who remained hypertriglyceridemic (200-499 mg/dL). They were treated them with the indicated dose of 4 g/d omega-3 acid ethyl esters (P-OM3) for 8 weeks. Measured oxylipins included mid-chain alcohols (HETEs, HEPEs and HDoHEs), ketones (KETEs), epoxides (as EpETrEs, EpETEs, and EpDPEs). At baseline, arachidonate-oxylipins (HETEs, KETEs, and EpETrEs) were most abundant in plasma with the greatest fraction of total abundance (mean |95% CI|) being carried in high density lipoproteins (HDL); 42% |31, 57| followed by very low density lipoproteins (VLDL); 27% |20, 36|; and LDL 21% |16, 28|. EPA- and DHA-derived oxylipins constituted less than 11% of total. HDL carried alcohols and epoxides but VLDL was also rich in ketones. Treatment decreased AA-derived oxylipins across lipoprotein classes (-23% |-33, -12|, p = 0.0003), and expanded EPA-(322% |241, 422|, plipoprotein class carries a unique oxylipin complement. P-OM3 treatment alters the oxylipin content of all classes, reducing pro-inflammatory and increasing anti-inflammatory species, consistent with the improved inflammatory and vascular status associated with the treatment. ClinicalTrials.gov NCT00959842.

comparison of various cholesterol lowering diets in young healthy volunteers : effects on serum lipoproteins and on other risk indicators for cardiovascular diseases

NARCIS (Netherlands)

Brussaard, J.H.

1981-01-01

This thesis deals with the effect of type and amount of dietary fat on the concentration and composition of serum lipoproteins, colonic function, plasma glucose and serum insulin levels and blood pressure in healthy human volunteers.

Two experiments were carried out. In the first experiment

The effect of interaction between Lipoprotein Lipase and ApoVLDL-II ...

African Journals Online (AJOL)

GREGO

2007-04-02

Apr 2, 2007 ... correlation between growth and fitness is not absolute, it ... significant differences are found in the plasma triglyceride ... (VLDL) and high density lipoprotein (HDL) concentration ... High-density lipoprotein cholesterol was.

Metabolism of lipoproteins by human fetal hepatocytes

International Nuclear Information System (INIS)

Carr, B.R.

1987-01-01

The rate of clearance of lipoproteins from plasma appears to play a role in the development of atherogenesis. The liver may account for as much as two thirds of the removal of low-density lipoprotein and one third of the clearance of high-density lipoprotein in certain animal species and humans, mainly by receptor-mediated pathways. The purpose of the present investigation was to determine if human fetal hepatocytes maintained in vitro take up and degrade lipoproteins. We first determined that the maximal binding capacity of iodine 125-iodo-LDL was approximately 300 ng of low-density lipoprotein protein/mg of membrane protein and an apparent dissociation constant of approximately 60 micrograms low-density lipoprotein protein/ml in membranes prepared from human fetal liver. We found that the maximal uptake of [ 125 I]iodo-LDL and [ 125 I]iodo-HDL by fetal hepatocytes occurred after 12 hours of incubation. Low-density lipoprotein uptake preceded the appearance of degradation products by 4 hours, and thereafter the degradation of low-density lipoprotein increased linearly for at least 24 hours. In contrast, high-density lipoprotein was not degraded to any extent by fetal hepatocytes. [ 125 I]Iodo-LDL uptake and degradation were inhibited more than 75% by preincubation with low-density lipoprotein but not significantly by high-density lipoprotein, whereas [ 125 I]iodo-HDL uptake was inhibited 70% by preincubation with high-density lipoprotein but not by low-density lipoprotein. In summary, human fetal hepatocytes take up and degrade low-density lipoprotein by a receptor-mediated process similar to that described for human extrahepatic tissues

Acrolein consumption induces systemic dyslipidemia and lipoprotein modification

International Nuclear Information System (INIS)

Conklin, Daniel J.; Barski, Oleg A.; Lesgards, Jean-Francois; Juvan, Peter; Rezen, Tadeja; Rozman, Damjana; Prough, Russell A.; Vladykovskaya, Elena; Liu, SiQi; Srivastava, Sanjay; Bhatnagar, Aruni

2010-01-01

Aldehydes such as acrolein are ubiquitous pollutants present in automobile exhaust, cigarette, wood, and coal smoke. Such aldehydes are also constituents of several food substances and are present in drinking water, irrigation canals, and effluents from manufacturing plants. Oral intake represents the most significant source of exposure to acrolein and related aldehydes. To study the effects of short-term oral exposure to acrolein on lipoprotein levels and metabolism, adult mice were gavage-fed 0.1 to 5 mg acrolein/kg bwt and changes in plasma lipoproteins were assessed. Changes in hepatic gene expression related to lipid metabolism and cytokines were examined by qRT-PCR analysis. Acrolein feeding did not affect body weight, blood urea nitrogen, plasma creatinine, electrolytes, cytokines or liver enzymes, but increased plasma cholesterol and triglycerides. Similar results were obtained with apoE-null mice. Plasma lipoproteins from acrolein-fed mice showed altered electrophoretic mobility on agarose gels. Chromatographic analysis revealed elevated VLDL cholesterol, phospholipids, and triglycerides levels with little change in LDL or HDL. NMR analysis indicated shifts from small to large VLDL and from large to medium-small LDL with no change in the size of HDL particles. Increased plasma VLDL was associated with a significant decrease in post-heparin plasma hepatic lipase activity and a decrease in hepatic expression of hepatic lipase. These observations suggest that oral exposure to acrolein could induce or exacerbate systemic dyslipidemia and thereby contribute to cardiovascular disease risk.

Acrolein consumption induces systemic dyslipidemia and lipoprotein modification

Energy Technology Data Exchange (ETDEWEB)

Conklin, Daniel J., E-mail: dj.conklin@louisville.ed [Diabetes and Obesity Center, University of Louisville, Louisville, KY 40202 (United States); Barski, Oleg A; Lesgards, Jean-Francois [Diabetes and Obesity Center, University of Louisville, Louisville, KY 40202 (United States); Juvan, Peter; Rezen, Tadeja; Rozman, Damjana [Centre for Functional Genomics and Bio-Chips (CFGBC), Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Zaloska 4, SI-1000 Ljubljana (Slovenia); Prough, Russell A [Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, KY 40202 (United States); Vladykovskaya, Elena; Liu, SiQi; Srivastava, Sanjay [Diabetes and Obesity Center, University of Louisville, Louisville, KY 40202 (United States); Bhatnagar, Aruni [Diabetes and Obesity Center, University of Louisville, Louisville, KY 40202 (United States); Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, KY 40202 (United States)

2010-02-15

Aldehydes such as acrolein are ubiquitous pollutants present in automobile exhaust, cigarette, wood, and coal smoke. Such aldehydes are also constituents of several food substances and are present in drinking water, irrigation canals, and effluents from manufacturing plants. Oral intake represents the most significant source of exposure to acrolein and related aldehydes. To study the effects of short-term oral exposure to acrolein on lipoprotein levels and metabolism, adult mice were gavage-fed 0.1 to 5 mg acrolein/kg bwt and changes in plasma lipoproteins were assessed. Changes in hepatic gene expression related to lipid metabolism and cytokines were examined by qRT-PCR analysis. Acrolein feeding did not affect body weight, blood urea nitrogen, plasma creatinine, electrolytes, cytokines or liver enzymes, but increased plasma cholesterol and triglycerides. Similar results were obtained with apoE-null mice. Plasma lipoproteins from acrolein-fed mice showed altered electrophoretic mobility on agarose gels. Chromatographic analysis revealed elevated VLDL cholesterol, phospholipids, and triglycerides levels with little change in LDL or HDL. NMR analysis indicated shifts from small to large VLDL and from large to medium-small LDL with no change in the size of HDL particles. Increased plasma VLDL was associated with a significant decrease in post-heparin plasma hepatic lipase activity and a decrease in hepatic expression of hepatic lipase. These observations suggest that oral exposure to acrolein could induce or exacerbate systemic dyslipidemia and thereby contribute to cardiovascular disease risk.

Correlation of structural stability with functional remodeling of high-density lipoproteins: the importance of being disordered.

Science.gov (United States)

Guha, Madhumita; Gao, Xuan; Jayaraman, Shobini; Gursky, Olga

2008-11-04

High-density lipoproteins (HDLs) are protein-lipid assemblies that remove excess cell cholesterol and prevent atherosclerosis. HDLs are stabilized by kinetic barriers that decelerate protein dissociation and lipoprotein fusion. We propose that similar barriers modulate metabolic remodeling of plasma HDLs; hence, changes in particle composition that destabilize HDLs and accelerate their denaturation may accelerate their metabolic remodeling. To test this notion, we correlate existing reports on HDL-mediated cell cholesterol efflux and esterification, which are obligatory early steps in cholesterol removal, with our kinetic studies of HDL stability. The results support our hypothesis and show that factors accelerating cholesterol efflux and esterification in model discoidal lipoproteins (including reduced protein size, reduced fatty acyl chain length, and/or increased level of cis unsaturation) destabilize lipoproteins and accelerate their fusion and apolipoprotein dissociation. Oxidation studies of plasma spherical HDLs show a similar trend: mild oxidation by Cu(2+) or OCl(-) accelerates cell cholesterol efflux, protein dissociation, and HDL fusion, while extensive oxidation inhibits these reactions. Consequently, moderate destabilization may be beneficial for HDL functions by facilitating insertion of cholesterol and lipophilic enzymes, promoting dissociation of lipid-poor apolipoproteins, which are primary acceptors of cell cholesterol, and thereby accelerating HDL metabolism. Therefore, HDL stability must be delicately balanced to maintain the structural integrity of the lipoprotein assembly and ensure structural specificity necessary for interactions of HDL with its metabolic partners, while facilitating rapid HDL remodeling and turnover at key junctures of cholesterol transport. The inverse correlation between HDL stability and remodeling illustrates the functional importance of structural disorder in macromolecular assemblies stabilized by kinetic barriers.

Effect of I125 on oxidation behavior of lipoprotein subpopulations

International Nuclear Information System (INIS)

Majtenyi, S.

2002-07-01

Lipoproteins play a central role in lipid metabolism. They serve as a transport vehicle for cholesterol and triglycerides keeping them in plasma in solution. Lipoproteins are characterized by the content of specific apoproteins and differences in the hydrated density ranges. Moreover, they are distinguished by electrophoretic mobility and other characteristics as high and low-density lipoproteins, respectively lipoprotein (a). More specifically, HDL is classified into HDL 2 and HDL 3 . In atherogenesis, lipoproteins are considered to play a key-role. Oxidatively modified LDL is selectively taken up via scavenger receptors of the macrophage-monocyte system. These cells are transformed into foam cells promoting atherogenesis in vessels in the subendothelial space. Oxidized HDL essentially appears to loose its protective effects on LDL and its beneficial function in reverse cholesterol transport. Thus, it turns proatherogenic. The effects various species of free radicals exert on lipoproteins are the reason for this oxidative modification. Thyroid function also influences lipoproteins in a complex manner. Based on their hydrated density ranges, lipoprotein subpopulations were fractionated and isolated via isopycnic density gradient ultracentrifugation. After investigation of the general oxidation behavior, initiated by addition of CuSO 4 to the isolated samples of HDL 3 , HDL 2 , LDL and Lp(a), the influence of different activities of radioiodine-125 on the kinetics of the formation of conjugated dienes was assessed. This was achieved by coincubation of plasma with I 125 . The spectrophotometrical measurement of the concentration of conjugated dienes in the course of CuSO 4 -induced lipid peroxidation leads to measurable changes in absorption at 234 nm. These changes in absorption over time result in a characteristically shaped curve graphically plotted. The shape of these curves mirrors different indicators of lipid peroxidation. Therefrom lag time, maximal

Effect of exercise and menstrual cycle status on plasma lipids, low density lipoprotein particle size, and apolipoproteins.

Science.gov (United States)

Lamon-Fava, S; Fisher, E C; Nelson, M E; Evans, W J; Millar, J S; Ordovas, J M; Schaefer, E J

1989-01-01

Habitual physical exercise has been reported to have beneficial effects on plasma lipoproteins. To examine this question in women, plasma cholesterol, triglyceride, and apolipoprotein (apo) A-I and B levels, and low density lipoprotein (LDL) particle size were determined in 25 women runners (9 of whom had exercise-related secondary amenorrhea) and 36 age-matched nonexercising women (controls). The eumenorrheic runners had significantly lower apo B levels and significantly greater mean apo A-I/apo B ratios and LDL particle sizes than did the control women (P less than 0.05). Lower apo B levels were correlated with decreased body mass index, a known exercise effect (P less than 0.0001). In addition, normally menstruating runners had cholesterol and triglyceride levels that were 7.6% and 25.4% lower, respectively, and apo A-I levels that were 6.4% higher than control women (P = NS). In amenorrheic runners all parameters were similar to values in control women, except that apo B levels were 20% lower (P less than 0.05). Amenorrheic runners had lower plasma apo A-I levels (13%) and significantly lower apo A-I/apo B ratios and estradiol levels than eumenorrheic runners, and serum estradiol values in the runners were correlated with apo A-I levels (P less than 0.01). These data indicate that the beneficial effects of strenuous exercise on plasma apo A-I levels and apo A-I/apo B ratios in women runners can be reversed by exercise-induced amenorrhea and decreased serum estradiol levels, and that women runners have lower apo B levels than nonexercising women, regardless of menstrual status.

Human luteinized granulosa cells secrete apoB100-containing lipoproteins

NARCIS (Netherlands)

Gautier, Thomas; Becker, Steffi; Drouineaud, Veronique; Menetrier, Franck; Sagot, Paul; Nofer, Jerzy-Roch; von Otte, Soeren; Lagrost, Laurent; Masson, David; Tietge, Uwe J. F.

Thus far, liver, intestine, heart, and placenta have been shown to secrete apolipoprotein (apo) B-containing lipoproteins. In the present study, we first investigated lipoproteins in human follicular fluid (FF), surrounding developing oocytes within the ovary, as well as in corresponding plasma

Relationship between Sustained Reductions in Plasma Lipid and Lipoprotein Concentrations with Apheresis and Plasma Levels and mRNA Expression of PTX3 and Plasma Levels of hsCRP in Patients with HyperLp(alipoproteinemia

Directory of Open Access Journals (Sweden)

Claudia Stefanutti

2016-01-01

Full Text Available The effect of lipoprotein apheresis (Direct Adsorption of Lipids, DALI (LA on plasma levels of pentraxin 3 (PTX3, an inflammatory marker that reflects coronary plaque vulnerability, and expression of PTX3 mRNA was evaluated in patients with hyperLp(alipoproteinemia and angiographically defined atherosclerosis/coronary artery disease. Eleven patients, aged 55±9.3 years (mean ± SD, were enrolled in the study. PTX3 soluble protein levels in plasma were unchanged by 2 sessions of LA; however, a downregulation of mRNA expression for PTX3 was observed, starting with the first session of LA (p<0.001. The observed reduction was progressively increased in the interval between the first and second LA sessions to achieve a maximum decrease by the end of the second session. A statistically significantly greater treatment-effect correlation was observed in patients undergoing weekly treatments, compared with those undergoing treatment every 15 days. A progressive reduction in plasma levels of C-reactive protein was also seen from the first session of LA, with a statistically significant linear correlation for treatment-effect in the change in plasma levels of this established inflammatory marker (R2=0.99; p<0.001. Our findings suggest that LA has anti-inflammatory and endothelium protective effects beyond its well-established efficacy in lowering apoB100-containing lipoproteins.

Membrane receptors for very low density lipoprotein (VLDL) inhibitor of lymphocyte proliferation

International Nuclear Information System (INIS)

Yi, P.I.; Beck, G.; Zucker, S.

1981-01-01

Physiologic concentrations of human plasma very low density lipoproteins inhibit the DNA synthesis of lymphocytes stimulated by allogeneic cells or lectins. In this report reachers have compared the effects of isolated lipoproteins [very low density lipoproteins (VLDL), low density lipoproteins (LDL), and high density lipoproteins (HDL)] and lipoprotein-depleted plasma (LDP) on DNA synthesis by phytohemagglutinin-stimulated human lymphocytes. The relative potency for the inhibition of lymphocyte proliferation was VLDL greater than LDL greater than HDL greater than LDP. Fifty percent inhibition of DNA synthesis was observed at a VLDL protein concentration of 1.5--2.0 microgram/ml. Researchers have further demonstrated the presence of specific receptors for VLDL on human lymphocytes. Native VLDL was more effective than LDL in competing for 125I-VLDL binding sites. Subsequent to binding to lymphocytes, 125I-VLDL was internalized and degraded to acid-soluble products. Based on a Scatchard analysis of VLDL binding at 4 degrees C, the number of VLDL receptors per lymphocyte was estimated at 28,000 +/- 1300. Based on an estimated mean binding affinity for the VLDL receptor complex at half saturation of approximately 8.8 X 10(7) liter/mole, it is estimated that 91% of lymphocyte VLDL receptors are occupied at physiologic VLDL concentrations in blood. Although the immune regulatory role of plasma lipoproteins is uncertain, researchers suggest tha VLDL and LDL-In may maintain circulating blood lymphocytes in a nonproliferative state via their respective cell receptor mechanisms

Plasma Lipoprotein(a Levels and Atherosclerotic Renal Artery Stenosis in Hypertensive Patients

Directory of Open Access Journals (Sweden)

Cristiana Catena

2015-03-01

Full Text Available Background/Aims: The contribution of emergent cardiovascular risk factors to atherosclerotic renal artery stenosis (ARAS is debated. We investigated the relationship of lipoprotein(a and prothrombotic factors with ARAS in hypertension. Methods: In 50 hypertensive patients with angiographic evidence of ARAS and 58 hypertensive patients who had comparable cardiovascular risk factor burden but no evidence of renovascular disease, we measured renal function, lipoprotein(a, homocysteine, and hemostatic-fibrinolytic markers. Results: Patients with ARAS were more frequently smokers and had longer duration of hypertension, heavier antihypertensive treatment, and worse renal function than controls. Lipoprotein(a was higher in patients with ARAS than controls, whereas no differences were found in homocysteine and all hemostatic variables. Multivariate analysis showed that lipoprotein(a was associated with ARAS independent of other confounders including renal function and history of coronary heart, cerebrovascular, and peripheral artery disease. Conclusion: Lipoprotein(a might contribute to the development of ARAS and detection of elevated levels of this lipoprotein could raise the suspicion of renovascular disease in patients with high blood pressure.

The biological properties of iron oxide core high-density lipoprotein in experimental atherosclerosis

NARCIS (Netherlands)

Skajaa, Torjus; Cormode, David P.; Jarzyna, Peter A.; Delshad, Amanda; Blachford, Courtney; Barazza, Alessandra; Fisher, Edward A.; Gordon, Ronald E.; Fayad, Zahi A.; Mulder, Willem J. M.

2011-01-01

Lipoproteins are a family of plasma nanoparticles responsible for the transportation of lipids throughout the body. High-density lipoprotein (HDL), the smallest of the lipoprotein family, measures 7-13 nm in diameter and consists of a cholesteryl ester and triglyceride core that is covered with a

Regulation of hepatic lipase activity by sphingomyelin in plasma lipoproteins.

Science.gov (United States)

Yang, Peng; Subbaiah, Papasani V

2015-10-01

Hepatic lipase (HL) is an important enzyme in the clearance of triacylglycerol (TAG) from the circulation, and has been proposed to have pro-atherogenic as well as anti-atherogenic properties. It hydrolyzes both phospholipids and TAG of lipoproteins, and its activity is negatively correlated with HDL levels. Although it is known that HL acts preferentially on HDL lipids, the basis for this specificity is not known, since it does not require any specific apoprotein for activity. In this study, we tested the hypothesis that sphingomyelin (SM), whose concentration is much higher in VLDL and LDL compared to HDL, is an inhibitor of HL, and that this could explain the lipoprotein specificity of the enzyme. The results presented show that the depletion of SM from normal lipoproteins activated the HL roughly in proportion to their SM content. SM depletion stimulated the hydrolysis of both phosphatidylcholine (PC) and TAG, although the PC hydrolysis was stimulated more. In the native lipoproteins, HL showed specificity for PC species containing polyunsaturated fatty acids at sn-2 position, and produced more unsaturated lyso PC species. The enzyme also showed preferential hydrolysis of certain TAG species over others. SM depletion affected the specificity of the enzyme towards PC and TAG species modestly. These results show that SM is a physiological inhibitor of HL activity in lipoproteins and that the specificity of the enzyme towards HDL is at least partly due to its low SM content. Published by Elsevier B.V.

Relationship between Sustained Reductions in Plasma Lipid and Lipoprotein Concentrations with Apheresis and Plasma Levels and mRNA Expression of PTX3 and Plasma Levels of hsCRP in Patients with HyperLp(a)lipoproteinemia

Science.gov (United States)

Stefanutti, Claudia; Mazza, Fabio; Steiner, Michael; Watts, Gerald F.; De Nève, Joel; Pasqualetti, Daniela; Paal, Juergen

2016-01-01

The effect of lipoprotein apheresis (Direct Adsorption of Lipids, DALI) (LA) on plasma levels of pentraxin 3 (PTX3), an inflammatory marker that reflects coronary plaque vulnerability, and expression of PTX3 mRNA was evaluated in patients with hyperLp(a)lipoproteinemia and angiographically defined atherosclerosis/coronary artery disease. Eleven patients, aged 55 ± 9.3 years (mean ± SD), were enrolled in the study. PTX3 soluble protein levels in plasma were unchanged by 2 sessions of LA; however, a downregulation of mRNA expression for PTX3 was observed, starting with the first session of LA (p < 0.001). The observed reduction was progressively increased in the interval between the first and second LA sessions to achieve a maximum decrease by the end of the second session. A statistically significantly greater treatment-effect correlation was observed in patients undergoing weekly treatments, compared with those undergoing treatment every 15 days. A progressive reduction in plasma levels of C-reactive protein was also seen from the first session of LA, with a statistically significant linear correlation for treatment-effect in the change in plasma levels of this established inflammatory marker (R 2 = 0.99; p < 0.001). Our findings suggest that LA has anti-inflammatory and endothelium protective effects beyond its well-established efficacy in lowering apoB100-containing lipoproteins. PMID:26903710

Recurrent Embolic Strokes of Undetermined Source in a Patient with Extreme Lipoprotein(a Levels

Directory of Open Access Journals (Sweden)

Zachary Bulwa

2016-08-01

Full Text Available Lipoprotein(a is a plasma lipoprotein and known cardiovascular risk factor most recently implicated in the development of high-risk carotid atherosclerotic plaques without significant carotid stenosis. We present a case of a young African-American female with recurrent embolic strokes of undetermined source. After our thorough investigation we identified the link between a small, irregular plaque in the right internal carotid artery and an extremely elevated plasma level of lipoprotein(a as the source of her embolic strokes.

Investigations on the transport and metabolism of high density lipoprotein cholesteryl esters in African green monkeys

International Nuclear Information System (INIS)

Sorci-Thomas, M.G.

1984-01-01

The metabolic fate of circulating high density lipoprotein cholesteryl esters was studied in African green monkeys to determine the significance of the lipid transfer reaction on the catabolism of lipoprotein cholesteryl esters. A method of doubly labeling both moieties of lipoprotein cholesteryl esters with [ 3 He]cholesteryl oleate and cholesteryl [ 14 C]oleate was developed for the purpose of studying plasma cholesteryl ester metabolism in vivo. In these studies the total plasma [ 3 He]cholesterol turnover resulted in production rates, which ranged from 10-17 mg/kg day, similar to previously reported values in African green monkeys and in normal lipoproteinemic humans. In contrast to the production rates calculated from the decay of plasma 3 He-radioactivity, the production rates calculated from lipoproteins labeled with cholesteryl [ 14 C]oleate were approximately 2-3 times greater. In addition to these studies, a plasma cholesteryl ester transacylation activity was demonstrated in vitro when HDL containing doubly labeled cholesteryl esters were incubated with fresh plasma. These results demonstrated that high density lipoprotein cholesteryl esters undergo transacylation in vitro, resulting in release and reesterification of free [ 3 H]cholesterol

Cholesterol synthesis by human fetal hepatocytes: effect of lipoproteins

International Nuclear Information System (INIS)

Carr, B.R.; Simpson, E.R.

1984-01-01

The purpose of the present investigation was to determine the effect of various lipoproteins on the rate of cholesterol synthesis of human fetal liver cells maintained in culture. This was accomplished by measuring the rate of incorporation of tritium from tritiated water or carbon 14-labeled acetate into cholesterol in human fetal liver cells. Optimal conditions for each assay were determined. When human fetal liver cells were maintained in the presence of low-density lipoprotein, cholesterol synthesis was inhibited in a concentration-dependent fashion. Intermediate--density lipoprotein and very-low-density lipoprotein also suppressed cholesterol synthesis in human fetal liver cells. In contrast, high-density lipoprotein stimulated cholesterol synthesis in human fetal liver cells. The results of the present as well as our previous investigations suggest that multiple interrelationships exist between fetal liver cholesterol synthesis and lipoprotein-cholesterol utilization by the human fetal adrenal gland and that these processes serve to regulate the lipoprotein-cholesterol levels in fetal plasma

Transvascular lipoprotein transport in patients with chronic renal disease

DEFF Research Database (Denmark)

Jensen, Trine Krogsgaard; Nordestgaard, Børge Grønne; Feldt-Rasmussen, Bo

2004-01-01

BACKGROUND: While increased plasma cholesterol is a well-established cardiovascular risk factor in the general population, this is not so among patients with chronic renal disease. We hypothesized that the transvascular lipoprotein transport, in addition to the lipoprotein concentration in plasma......, determines the degree of atherosclerosis among patients with chronic renal disease. METHODS: We used an in vivo method for measurement of transvascular transport of low-density lipoprotein (LDL) in 21 patients with chronic renal disease and in 42 healthy control patients. Autologous 131-iodinated LDL...... was reinjected intravenously, and the 1-hour fractional escape rate was taken as index of transvascular transport. RESULTS: Transvascular LDL transport tended to be lower in patients with chronic renal disease than in healthy control patients [3.3 (95% CI 2.4-4.2) vs. 4.2 (3.7-4.2)%/hour; NS]. However...

Plasma lipoprotein(a) levels in patients with homozygous autosomal dominant hypercholesterolemia

NARCIS (Netherlands)

Sjouke, B.; Yahya, R.; Tanck, M.W.T.; Defesche, J.C.; Graaf, J. de; Wiegman, A.; Kastelein, J.J.; Mulder, M.T.; Hovingh, G.K.; Roeters van Lennep, J.E.

2017-01-01

BACKGROUND: Patients with autosomal dominant hypercholesterolemia (ADH), caused by mutations in either low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin-kexin type 9 (PCSK9) are characterized by high low-density lipoprotein cholesterol levels and

Plasma lipoprotein(a) levels in patients with homozygous autosomal dominant hypercholesterolemia

NARCIS (Netherlands)

Sjouke, Barbara; Yahya, Reyhana; Tanck, Michael W. T.; Defesche, Joep C.; de Graaf, Jacqueline; Wiegman, Albert; Kastelein, John J. P.; Mulder, Monique T.; Hovingh, G. Kees; Roeters van Lennep, Jeanine E.

2017-01-01

Patients with autosomal dominant hypercholesterolemia (ADH), caused by mutations in either low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin-kexin type 9 (PCSK9) are characterized by high low-density lipoprotein cholesterol levels and in some

High Density Lipoprotein and it's Dysfunction.

Science.gov (United States)

Eren, Esin; Yilmaz, Necat; Aydin, Ozgur

2012-01-01

Plasma high-density lipoprotein cholesterol(HDL-C) levels do not predict functionality and composition of high-density lipoprotein(HDL). Traditionally, keeping levels of low-density lipoprotein cholesterol(LDL-C) down and HDL-C up have been the goal of patients to prevent atherosclerosis that can lead to coronary vascular disease(CVD). People think about the HDL present in their cholesterol test, but not about its functional capability. Up to 65% of cardiovascular death cannot be prevented by putative LDL-C lowering agents. It well explains the strong interest in HDL increasing strategies. However, recent studies have questioned the good in using drugs to increase level of HDL. While raising HDL is a theoretically attractive target, the optimal approach remains uncertain. The attention has turned to the quality, rather than the quantity, of HDL-C. An alternative to elevations in HDL involves strategies to enhance HDL functionality. The situation poses an opportunity for clinical chemists to take the lead in the development and validation of such biomarkers. The best known function of HDL is the capacity to promote cellular cholesterol efflux from peripheral cells and deliver cholesterol to the liver for excretion, thereby playing a key role in reverse cholesterol transport (RCT). The functions of HDL that have recently attracted attention include anti-inflammatory and anti-oxidant activities. High antioxidant and anti-inflammatory activities of HDL are associated with protection from CVD.This review addresses the current state of knowledge regarding assays of HDL functions and their relationship to CVD. HDL as a therapeutic target is the new frontier with huge potential for positive public health implications.

Effects of chromium-enriched bacillus subtilis KT260179 supplementation on chicken growth performance, plasma lipid parameters, tissue chromium levels, cecal bacterial composition and breast meat quality.

Science.gov (United States)

Yang, Jiajun; Qian, Kun; Zhang, Wei; Xu, Yayuan; Wu, Yijing

2016-11-08

Both chromium (Cr) and probiotic bacillus own the virtues of regulating animal metabolism and meat quality. Purpose of this study was to evaluate the efficiency of supplemental Cr and bacillus in the form of chromium-enriched Bacillus subtilis KT260179 (CEBS) on chicken growth performance, plasma lipid parameters, tissue chromium levels, cecal bacterial composition and breast meat quality. Six hundred of 1-day-old Chinese Huainan Partridge chickens were divided into four groups randomly: Control, inorganic Cr, Bacillus subtilis, and CEBS. The feed duration was 56 days. After 28 days of treatment, broiler feed CEBS or normal B. subtilis had higher body weights than control broiler, and after 56 days, chickens given either CEBS or B. subtilis had greater body weights than control broiler or those given inorganic Cr. Plasma total cholesterol, triglycerides, and low density lipoprotein cholesterol levels declined significantly in the CEBS group compared with the control, whereas plasma high density lipoprotein cholesterol levels increased significantly. The concentration of Cr in blood and breast muscle increased after CEBS and inorganic Cr supplementation. B. subtilis and CEBS supplementation caused a significant increase in the numbers of Lactobacillus and Bifidobacterium in the caecum, while the numbers of Escherichia coli and Salmonella decreased significantly compared to the control. Feed adding CEBS increased the lightness, redness, and yellowness of breast meat, improved the water-holding capacity, decreased the shear force and cooking loss. In all, CEBS supplementation promoted body growth, improved plasma lipid parameters, increased tissue Cr concentrations, altered cecal bacterial composition and improved breast meat quality.

Prebeta-migrating high density lipoprotein: quantitation in normal and hyperlipidemic plasma by solid phase radioimmunoassay following electrophoretic transfer

International Nuclear Information System (INIS)

Ishida, B.Y.; Frolich, J.; Fielding, C.J.

1987-01-01

A quantitative solid phase immunoassay has been developed for the determination of the mass of electrophoretically separated prebeta apolipoprotein A-I (apoA-I) in human plasma. Conditions have been identified for the quantitative transfer and immunoblotting of the apolipoprotein in the absence of organic solvents or detergents. In normolipidemic plasma, the prebeta-migrating fraction of apoA-I represented 4.2 +/- 1.8% of total apoA-I (61 +/- 26 micrograms of apoA-I per ml of plasma). Significantly higher levels were found in hypercholesterolemia of genetic origin, in primary and secondary hypertriglyceridemia, and in congenital lecithin:cholesterol acyltransferase deficiency. In all cases prebeta-migrating apoA-I consisted in large part of low molecular weight lipoprotein species, compared to the size of the major, alpha-migrating apoA-I fraction

Serum amyloid A is found on ApoB-containing lipoproteins in obese humans with diabetes.

Science.gov (United States)

Jahangiri, Anisa; Wilson, Patricia G; Hou, Tianfei; Brown, Aparna; King, Victoria L; Tannock, Lisa R

2013-05-01

In murine models of obesity/diabetes, there is an increase in plasma serum amyloid A (SAA) levels along with redistribution of SAA from high-density lipoprotein (HDL) to apolipoprotein B (apoB)-containing lipoprotein particles, namely, low-density lipoprotein and very low-density lipoprotein. The goal of this study was to determine if obesity is associated with similar SAA lipoprotein redistribution in humans. Three groups of obese individuals were recruited from a weight loss clinic: healthy obese (n = 14), metabolic syndrome (MetS) obese (n = 8), and obese with type 2 diabetes (n = 6). Plasma was separated into lipoprotein fractions by fast protein liquid chromatography, and SAA was measured in lipid fractions using enzyme-linked immunosorbent assay and Western blotting. Only the obese diabetic group had SAA detectable in apoB-containing lipoproteins, and SAA reverted back to HDL with active weight loss. In human subjects, SAA is found in apoB-containing lipoprotein particles only in obese subjects with type 2 diabetes, but not in healthy obese or obese subjects with MetS. Copyright © 2012 The Obesity Society.

Apolipoprotein(a) phenotypes and lipoprotein(a) concentrations in patients with hyperthyroidism

DEFF Research Database (Denmark)

Klausen, I C; Hegedüs, L; Hansen, P S

1995-01-01

Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL) particle in which apolipoprotein B-100 (apoB) is attached to a glycoprotein called apolipoprotein(a) [apo(a)]. Apo(a) has several genetically determined phenotypes differing in molecular weight, to which Lp(a) concentrations in plasma are ...

Normal and abnormal lipid and lipoprotein metabolism

African Journals Online (AJOL)

2009-03-20

Mar 20, 2009 ... This article focuses on lipid and lipoprotein metabolism and introduces a range of genetic ... spherical structures that are suspended in the plasma and whose ..... atherosclerosis. Table II suggests a simple classification of.

A cross-linking study on the particle species of human plasma high density lipoproteins.

Science.gov (United States)

Yachida, Y; Minari, O

1983-08-01

The present investigation was on the particle species of human plasma high density lipoprotein (HDL) characterized by the stoichiometry of their apoprotein components. HDL2-1, HDL2-2, HDL3-1, and HDL3-2 isolated from normal human plasma by sequential ultracentrifugal flotation were further subfractionated by Bio Gel A-5m gel chromatography or hydroxyapatite column chromatography, and three distinct subfractions were obtained. Subfraction 1 was obtained from all the HDL fractions and it contained mostly apolipoprotein A-I (A-I). Subfraction 2 was obtained from HDL2-2 and HDL3-1 and it contained A-I and apolipoprotein A-II (A-II) in the molar ratio of one to one, and subfraction 3 from HDL2-2 and HDL3-1 contained A-I and apolipoprotein C (C). Each subfraction was treated with bifunctional cross-linking reagents, and the intraparticle cross-linked products of apolipoproteins were examined by SDS-polyacrylamide gel electrophoresis. The results of the cross-linking studies indicated that the HDL2 fraction consisted mainly of lipoprotein particles of the (A-I)4 type and a few of the (A-I)5, (A-I)2(A-II)2, and (A-I)4(C)2 types, and that the HDL3 fraction consisted mainly of (A-I)2(A-II)2 type particles and a few (A-I)4, (A-I)3, (A-I)2, (A-I), and (A-I)3(C)2 type particles. From the results of analyses of the lipid components in the HDL of each type, it was suggested that the function of the particle species of the (A-I)n type (n = 1--5), which contained more cholesteryl ester than the (A-I)2(A-II)2 type, was concerned mainly with cholesterol metabolism.

Low-density lipoprotein cholesterol and risk of gallstone disease

DEFF Research Database (Denmark)

Stender, Stefan; Frikke-Schmidt, Ruth; Benn, Marianne

2013-01-01

Drugs which reduce plasma low-density lipoprotein cholesterol (LDL-C) may protect against gallstone disease. Whether plasma levels of LDL-C per se predict risk of gallstone disease remains unclear. We tested the hypothesis that elevated LDL-C is a causal risk factor for symptomatic gallstone...

Pyrene-Labeled Amphiphiles: Dynamic And Structural Probes Of Membranes And Lipoproteins

Science.gov (United States)

Pownall, Henry J.; Homan, Reynold; Massey, John B.

1987-01-01

Lipids and proteins are important functional and structural components of living organisms. Although proteins are frequently found as soluble components of plasma or the cell cytoplasm, many lipids are much less soluble and separate into complex assemblies that usually contain proteins. Cell membranes and plasma lipoproteins' are two important macro-molecular assemblies that contain both lipids and proteins. Cell membranes are composed of a variety of lipids and proteins that form an insoluble bilayer array that has relatively little curvature over distances of several nm. Plasma lipoproteins are different in that they are much smaller, water-soluble, and have highly curved surfaces. A model of a high density lipoprotein (HDL) is shown in Figure 1. This model (d - 10 nm) contains a surface of polar lipids and proteins that surrounds a small core of insoluble lipids, mostly triglycerides and cholesteryl esters. The low density (LDL) (d - 25 nm) and very low density (VLDL) (d 90 nm) lipoproteins have similar architectures, except the former has a cholesteryl ester core and the latter a core that is almost exclusively triglyceride (Figure 1). The surface proteins of HDL are amphiphilic and water soluble; the single protein of LDL is insoluble, whereas VLDL contains both soluble and insoluble proteins. The primary structures of all of these proteins are known.

Accumulation of Oxidized Low-Density Lipoprotein in Psoriatic Skin and Changes of Plasma Lipid Levels in Psoriatic Patients

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Nilgun Solak Tekin

2007-01-01

Full Text Available Background. Psoriasis is a chronic inflammatory skin disease characterized by an accelerated turnover of epidermal cells and an incomplete differentiation in epidermis with lesion. However, the exact etiology of psoriasis is unknown. Abnormalities in essential fatty acid metabolism, free radical generation, lipid peroxidation, and release of lymphokines have been proposed. Objective. Our purpose was to evaluate the plasma lipids and oxidized low-density lipoprotein accumulation in psoriatic skin lesion in order to ascertain the possible participation of oxidative stress and oxidative modification of lipids in pathogenesis of psoriasis. Methods. The study group included 84 patients with psoriasis, and 40 sex- and age-matched healthy volunteers. Blood lipid profile was determined. Psoriatic and nonlesional skin samples of psoriatic patients were evaluated for the presence of oxidized low-density lipoprotein by using an immune-fluorescent staining method. Results. The mean levels of lipids (total cholesterol, triglyceride, and LDL cholesterol in patients with psoriasis were found to be significantly higher than those of healthy subjects. Psoriatic skins were shown positive oxidized low-density lipoprotein staining. There was no staining in nonlesional skin samples of the same individuals. Conclusion. Lipid peroxidation mediated by free radicals is believed to be one of the important causes of cell membrane destruction and cell damage. This study shows for the first time the accumulation of oxidized low-density lipoprotein in psoriatic skin lesion. We believe that accumulation of ox-LDL in psoriatic skin may have an important role in the immune-inflammatory events that result in progressive skin damage.

Obtention of scintillography images by low density lipoproteins labelled with technetium 99

International Nuclear Information System (INIS)

Silva, S.; Coelho, I.; Zanardo, E.; Pileggi, F.; Meneguethi, C.; Maranhao, R.C.

1992-01-01

The low density lipoproteins carry the most part of the cholesterol in the blood plasma. These lipoproteins are labelled with technetium-99-m and have been used for obtaining images in nuclear medicine. The introduction of this technique is presented, aiming futures clinical uses. Scintillographic images are obtained 25 minutes and 24 hours after the injection of 3 m Ci of low density lipoproteins - technetium-99 m in rabbits. (C.G.C.)

Oxidative stress and plasma lipoproteins in cancer patients

Energy Technology Data Exchange (ETDEWEB)

Maia, Fernanda Maria Machado; Santos, Emanuelly Barbosa; Reis, Germana Elias [Universidade Estadual do Ceará, Fortaleza, CE (Brazil)

2014-07-01

To evaluate the relation between oxidative stress and lipid profile in patients with different types of cancer. This was an observational cross-sectional. A total of 58 subjects were evaluated, 33 males, divided into two groups of 29 patients each: Group 1, patients with cancer of the digestive tract and accessory organs; Group 2 patients with other types of cancers, all admitted to a public hospital. The plasma levels (lipoproteins and total cholesterol, HDL, and triglycerides, for example) were analyzed by enzymatic kits, and oxidative stress based on thiobarbituric acid-reactive substances, by assessing the formation of malondialdehyde. In general the levels of malondialdehyde of patients were high (5.00μM) as compared to 3.31μM for healthy individuals. The median values of lipids exhibited normal triacylglycerol (138.78±89.88mg/dL), desirable total cholesterol values (163.04±172.38mg/dL), borderline high LDL (151.30±178.25mg/dL) and low HDL (31.70±22.74mg/dL). Median HDL levels in Group 1 were lower (31.32mg/dL) than the cancer patients in Group 2 (43.67mg/dL) (p=0.038). Group 1 also showed higher levels of oxidative stress (p=0.027). The lipid profile of patients with cancer was not favorable, which seems to have contributed to higher lipid peroxidation rate, generating a significant oxidative stress.

Lipoprotein lipase: genetics, lipid uptake, and regulation.

Science.gov (United States)

Merkel, Martin; Eckel, Robert H; Goldberg, Ira J

2002-12-01

Lipoprotein lipase (LPL) regulates the plasma levels of triglyceride and HDL. Three aspects are reviewed. 1) Clinical implications of human LPL gene variations: common mutations and their effects on plasma lipids and coronary heart disease are discussed. 2) LPL actions in the nervous system, liver, and heart: the discussion focuses on LPL and tissue lipid uptake. 3) LPL gene regulation: the LPL promoter and its regulatory elements are described.

Effects of estrogen on very low-density lipoprotein triglyceride metabolism in fed and fasted chicks

International Nuclear Information System (INIS)

Park, J.R.

1988-01-01

A single injection of estrogen into growing chicks resulted in a marked elevation in plasma triglyceride (TG) followed by phospholipid (PL) and cholesterol (CH) in both fed and fasted chicks. Estrogen caused a development of massive fatty liver in fed chicks. Hepatic malic enzyme and glucose-6-phosphate dehydrogenase activities also increased significantly in fed chicks and, to a small extent, in fasted chicks. Very low density lipoproteins (VLDL) were barely detectable in the fasted control plasma. However, the VLDL concentration increased markedly upon estrogen injection, becoming the most prevalent lipoprotein in the plasma. The administration of estrogen resulted in an increase in oleic acid and a decrease in linoleic acid content except in the cholesteryl ester of VLDL and LDL. VLDL of estrogenized birds had β-mobility on agarose gel electrophoresis, and they eluted in two peaks on agarose gel filtration chromatography. Both peaks on gel filtration exhibited the same β-mobility on agarose gel electrophoresis. Nevertheless, the apoprotein composition of these two peaks were substantially different from each other; apo B was not present in the first peak VLDL. VLDL-TG kinetic studies conducted in vivo, using 14 C-TG-VLDL prepared endogenously from control and estrogenized chicks revealed that VLDL-TG produced from the former had a higher fractional catabolic rate (FCR) than VLDL-TG from the latter

Characterization of lipoproteins in human and canine cerebrospinal fluid (CSF)

International Nuclear Information System (INIS)

Pitas, R.E.; Weisgraber, K.H.; Boyles, J.K.; Lee, S.; Mahley, R.W.

1986-01-01

Previously the authors demonstrated that rat brain astrocytes in vitro synthesize and secrete apo-E and possess apo-B,E(LDL) receptors. The apo-E secreted by astrocytes and apo-E in rat brain extracts differed from serum apo-E in two respects. Brain apo-E had a higher apparent molecular weight and a higher percentage of more acidic isoforms. To characterize further the apo-E within the central nervous system, apo-E in human and canine CSF was investigated. Compared to plasma apo-E, CSF apo-E had a higher apparent M/sub r/ and a higher percentage of acidic isoforms which were sialylated, as shown by neuraminidase digestion. The apo-E in human CSF was approx.5-10% of the plasma level. In CSF 60-80% of the apo-E was in lipoproteins with d = 1.09-1.15. The remainder of the apo-E was in the d > 1.21 fraction. Human CSF lipoproteins were primarily spherical (110-190 A) while canine CSF lipoproteins were a mixture of discs (205 x 65 A) while canine CSF lipoproteins were a mixture of discs (205 x 65 A) and spheres (100-150 A). The CSF also contained apo-AI in the d = 1.09-1.15 g/ml fraction. Human CSF lipoproteins containing both apo-E and apo-AI were isolated on an anti-apo-E affinity column, suggesting that apo-E and AI occurred in the same particles. The CSF apo-E-containing lipoproteins competed for binding of 125 I-LDL to the apo-B,E(LDL) receptor. There was no detectable apo-B in CSF. These data suggest that CSF lipoproteins might transport lipid and regulate lipid homeostasis within the brain

Lifecycle of a Lipoprotein from a Biophysical Perspective

Science.gov (United States)

Rutledge, John C.; Huser, Thomas; Voss, John; Chan, James; Parikh, Atul

The goal of our project was to understand how lipids and lipoproteins interact with cell membranes. This chapter will present the five major areas in which we have focused our attention on understanding how lipids and lipoproteins interact with cell membranes (Fig. 11.1): (1) triglycerides and vascular injury, (2) single lipoprotein analysis, (3) apolipoprotein E (apoE) conformation changes in the postprandial state, (4) triglyceride-rich lipoproteins (TGRLs) and endothelial cell inflammation, and (5) TGRL lipolysis products and monocyte activation. For over a hundred years, Western civilization has questioned how the food we eat translates into disease, and specifically atherosclerotic cardiovascular disease. Although most information indicates that this basic pathophysiological process is mediated through consumption of excess saturated fats, much remains unknown. After humans eat a meal, there is an elevation of triglycerides in the blood in the postprandial state. In normal individuals, triglycerides can rise after a meal by 50 to 100%. This has been documented many times in the past, including a paper by Hyson et al, (1998) [1]. In that study, normal healthy individuals were given a 40%-fat meal. Plasma triglycerides, which were modestly elevated initially, rose about 60% higher three to four hours after ingestion of the meal. Subsequently plasma triglycerides fell to baseline levels six hours after the meal. Even in these healthy individuals, a significant elevation of triglycerides was noted after ingestion of a moder ately high-fat meal.

Lipoprotein metabolism in familial hypercholesterolemia: Serial assessment using a one-step ultracentrifugation method

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Hayato Tada

2015-04-01

Full Text Available Objectives: It is well known that familial hypercholesterolemia (FH is a common inherited disorder that can markedly elevate the level of plasma LDL cholesterol. However, little data exists regarding the clinical impact of the plasma triglyceride (TG-rich lipoprotein fraction, including VLDL and IDL, in FH. Thus, we assessed the hypothesis that the mutations in the LDL receptor modulate lipoprotein metabolism other than the LDL fraction. Design and methods: We investigated plasma lipoprotein with a one-step ultracentrifugation method for 146 controls (mean age=61.4±17.1 yr, mean LDL cholesterol=92.7±61.2 mg/dl, 213 heterozygous mutation-determined FH subjects (mean age=46.0±18.0 yr, mean LDL cholesterol=225.1±61.2 mg/dl, and 16 homozygous/compound heterozygous mutation-determined FH subjects (mean age=26.9±17.1 yr, mean LDL cholesterol=428.6±86.1 mg/dl. In addition, we evaluated cholesterol/TG ratio in each lipoprotein fraction separated by ultracentrifugation. Results: In addition to total cholesterol and LDL cholesterol levels, VLDL cholesterol (19.5±10.4, 25.2±19.3, 29.5±21.4 mg/dl, respectively and IDL cholesterol (8.3±3.7, 16.8±11.5, 40.0±37.3 mg/dl, respectively exhibited a tri-model distribution according to their status in LDL receptor mutation(s. Moreover, the ratios of cholesterol/TG of each lipoprotein fraction increased significantly in heterozygous FH and homozygous/compound heterozygous FH groups, compared with that of controls, suggesting that the abnormality in LDL receptor modulates the quality as well as the quantity of each lipoprotein fraction. Conclusions: Our results indicate that cholesterol in TG-rich lipoproteins, including VLDL and IDL, are significantly higher in FH subjects, revealing a tri-modal distribution according to the number of LDL receptor mutations. Keywords: LDL cholesterol, Familial hypercholesterolemia, Ultracentrifugation, Lipoprotein

Achieving secondary prevention low-density lipoprotein particle concentration goals using lipoprotein cholesterol-based data.

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Simon C Mathews

Full Text Available BACKGROUND: Epidemiologic studies suggest that LDL particle concentration (LDL-P may remain elevated at guideline recommended LDL cholesterol goals, representing a source of residual risk. We examined the following seven separate lipid parameters in achieving the LDL-P goal of <1000 nmol/L goal for very high risk secondary prevention: total cholesterol to HDL cholesterol ratio, TC/HDL, <3; a composite of ATP-III very high risk targets, LDL-C<70 mg/dL, non-HDL-C<100 mg/dL and TG<150 mg/dL; a composite of standard secondary risk targets, LDL-C<100, non-HDL-C<130, TG<150; LDL phenotype; HDL-C ≥ 40; TG<150; and TG/HDL-C<3. METHODS: We measured ApoB, ApoAI, ultracentrifugation lipoprotein cholesterol and NMR lipoprotein particle concentration in 148 unselected primary and secondary prevention patients. RESULTS: TC/HDL-C<3 effectively discriminated subjects by LDL-P goal (F = 84.1, p<10(-6. The ATP-III very high risk composite target (LDL-C<70, nonHDL-C<100, TG<150 was also effective (F = 42.8, p<10(-5. However, the standard secondary prevention composite (LDL-C<100, non-HDL-C<130, TG<150 was also effective but yielded higher LDL-P than the very high risk composite (F = 42.0, p<10(-5 with upper 95% confidence interval of LDL-P less than 1000 nmol/L. TG<150 and TG/HDL-C<3 cutpoints both significantly discriminated subjects but the LDL-P upper 95% confidence intervals fell above goal of 1000 nmol/L (F = 15.8, p = 0.0001 and F = 9.7, p = 0.002 respectively. LDL density phenotype neared significance (F = 2.85, p = 0.094 and the HDL-C cutpoint of 40 mg/dL did not discriminate (F = 0.53, p = 0.47 alone or add discriminatory power to ATP-III targets. CONCLUSIONS: A simple composite of ATP-III very high risk lipoprotein cholesterol based treatment targets or TC/HDL-C ratio <3 most effectively identified subjects meeting the secondary prevention target level of LDL-P<1000 nmol/L, providing a potential alternative to advanced lipid testing in many clinical

Lowering Low-Density Lipoprotein Particles in Plasma Using Dextran Sulphate Co-Precipitates Procoagulant Extracellular Vesicles

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Jiong-Wei Wang

2017-12-01

Full Text Available Plasma extracellular vesicles (EVs are lipid membrane vesicles involved in several biological processes including coagulation. Both coagulation and lipid metabolism are strongly associated with cardiovascular events. Lowering very-low- and low-density lipoprotein ((VLDL particles via dextran sulphate LDL apheresis also removes coagulation proteins. It remains unknown, however, how coagulation proteins are removed in apheresis. We hypothesize that plasma EVs that contain high levels of coagulation proteins are concomitantly removed with (VLDL particles by dextran sulphate apheresis. For this, we precipitated (VLDL particles from human plasma with dextran sulphate and analyzed the abundance of coagulation proteins and EVs in the precipitate. Coagulation pathway proteins, as demonstrated by proteomics and a bead-based immunoassay, were over-represented in the (VLDL precipitate. In this precipitate, both bilayer EVs and monolayer (VLDL particles were observed by electron microscopy. Separation of EVs from (VLDL particles using density gradient centrifugation revealed that almost all coagulation proteins were present in the EVs and not in the (VLDL particles. These EVs also showed a strong procoagulant activity. Our study suggests that dextran sulphate used in LDL apheresis may remove procoagulant EVs concomitantly with (VLDL particles, leading to a loss of coagulation proteins from the blood.

Activation of lipoprotein lipase by lipoprotein fractions of human serum.

Science.gov (United States)

Bier, D M; Havel, R J

1970-11-01

Triglycerides in fat emulsions are hydrolyzed by lipoprotein lipase only when they are "activated" by serum lipoproteins. The contribution of different lipoprotein fractions to hydrolysis of triglycerides in soybean oil emulsion was assessed by determining the quantity of lipoprotein fraction required to give half-maximal hydrolysis. Most of the activator property of whole serum from normolipidemic, postabsorptive subjects was in high density lipoproteins. Low density lipoproteins and serum from which all lipoprotein classes were removed had little or no activity. Also, little activator was present in guinea pig serum or in very low density poor serum from an individual with lecithin:cholesterol acyltransferase deficiency, both of which are deficient in high density lipoproteins. Human very low density lipoproteins are potent activators and are much more active than predicted from their content of high density lipoprotein-protein. Per unit weight of protein, very low density lipoproteins had 13 times the activity of high density lipoproteins. These observations suggest that one or more of the major apoproteins of very low density lipoproteins, present as a minor constituent of high density lipoproteins, may be required for the activation process.

IS LIPOPROTEIN (A A PREDICTOR OF CORONARY ARTERY DISEASE SEVERITY?

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Tayyebeh Miandoabi

2010-12-01

Full Text Available Abstract    INTRODUCTION: Studies on the association between the plasma concentration of lipoprotein (a and coronary heart disease (CHD have reported conflicting findings.    METHOD AND MATERIALS: The objective of the present study was to evaluate the association between serum levels of lipoprotein (a and ischemic heart disease as well as other cardiovascular risk factors in a population-based study. Lipoprotein (a serum was measured in 142 patients with chronic stable angina undergoing clinically indicated coronary angiography. Lipid profile, fasting blood glucose, anthropometric and clinical parameters were analyzed.    RESULTS: Lipoprotein (a levels were significantly associated with coronary artery stenosis in men, but not in women. Also, an direct association between mean levels of lipoprotein (a and coronary artery stenosis in men younger than 55 years old and an inverse association in men older than 55 years old were observed.     CONCLUSION: Multivariate analysis revealed that lipoprotein (a was considered an independent predictor for severity of CAD in men, especially in younger ages.      Keywords: Lipoprotein (a, cardiovascular risk factors, Ischemic heart disease, coronary angiography.

Influence of a healthy Nordic diet on serum fatty acid composition and associations with blood lipoproteins – results from the NORDIET study

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Viola Adamsson

2014-12-01

Full Text Available Background: The fatty acid (FA composition of serum lipids is related to the quality of dietary fat intake. Objective: To investigate the effects of a healthy Nordic diet (ND on the FA composition of serum cholesterol esters (CE-FA and assess the associations between changes in the serum CE-FA composition and blood lipoproteins during a controlled dietary intervention. Design: The NORDIET trial was a 6-week randomised, controlled, parallel-group dietary intervention study that included 86 adults (53±8 years with elevated low-density lipoprotein cholesterol (LDL-C. Serum CE-FA composition was measured using gas chromatography. Diet history interviews were conducted, and daily intake was assessed using checklists. Results: Food and nutrient intake data indicated that there was a reduction in the intake of fat from dairy and meat products and an increase in the consumption of fatty fish with the ND. The levels of saturated fatty acids in cholesterol esters (CE-SFA 14:0, 15:0, and 18:0, but not 16:0, showed a significant decrease after intake of ND compared to the control diet (p<0.01. Also, a significant increase in serum 22:6n – 3 was observed compared with the control diet (p<0.01. The changes in CE-SFA 14:0, 15:0, and 18:0 correlated positively with changes in LDL-C, HDL-C, LDL-C/HDL-C, ApoA1, and ApoB (p<0.01, respectively, whereas the changes in polyunsaturated fatty acids in cholesterol esters (CE-PUFA 22:6n – 3 were negatively correlated with changes in the corresponding serum lipids. Conclusions: The decreased intake of saturated fat and increased intake of n-3 PUFA in a healthy ND is partly reflected by changes in the serum CE-FA composition, which are associated with an improved serum lipoprotein pattern.

Increased oxidizability of low-density lipoproteins in hypothyroidism

NARCIS (Netherlands)

Diekman, T.; Demacker, P. N.; Kastelein, J. J.; Stalenhoef, A. F.; Wiersinga, W. M.

1998-01-01

Hypothyroidism leads to an increase of plasma low-density lipoprotein (LDL) cholesterol levels. Oxidation of LDL particles changes their intrinsic properties, thereby enhancing the development of atherosclerosis. T4 has three specific binding sites on apolipoprotein B; furthermore it inhibits LDL

Modelling of a multi-temperature plasma composition

International Nuclear Information System (INIS)

Liani, B.; Benallal, R.; Bentalha, Z.

2005-01-01

Knowledge of plasma composition is very important for various plasma applications and prediction of plasma properties. The authors use the Saha equation and Debye length equation to calculate the non-local thermodynamic-equilibrium plasma composition. It has been shown that the model to 2T with T representing the temperature (electron temperature and heavy-particle temperature) described by Chen and Han [J. Phys. D 32(1999)1711] can be applied for a mixture of gases, where each atomic species has its own temperature, but the model to 4T is more general because it can be applicable to temperatures distant enough of the heavy particles. This can occur in a plasma composed of big- or macro-molecules. The electron temperature T e varies in the range 8000∼20000 K at atmospheric pressure. (authors)

Carotid intima media thickness is associated with plasma lipoprotein-associated phospholipase A(2) mass in nondiabetic subjects but not in patients with type 2 diabetes

NARCIS (Netherlands)

Constantinides, Alexander; van Pelt, L. Joost; van Leeuwen, Jeroen J. J.; de Vries, Rindert; Tio, Rene A.; van der Horst, Iwan C. C.; Sluiter, Wim J.; Dullaart, Robin P. F.

Background A recent meta-analysis showed that both plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) mass and activity independently predict cardiovascular events. Notably, Lp-PLA(2) activity but not mass was found to be a determinant of cardiovascular outcome in type 2 diabetes mellitus.

Uptake of [3H]vitamin D3 from low and high density lipoproteins by cultured human fibroblasts

International Nuclear Information System (INIS)

Shireman, R.B.; Williams, D.; Remsen, J.F.

1986-01-01

The plasma distribution and cellular uptake of [ 3 H]vitamin D 3 was studied in vitro using cultured human fibroblasts. Incubation of [ 3 H]vitamin D 3 (cholecalciferol) with plasma followed by sequential ultracentrifugal fractionation of the lipoproteins indicated that 2-4% of the radioactivity associated with the very low density lipoprotein (VLDL), 12% with low density lipoprotein (LDL), and approximately 60% with the high density lipoprotein (HDL). The remaining radioactivity, 25%, was associated with the sedimented plasma fractions. By comparison, an average of 86% of the radioactivity from [ 3 H] 1,25-dihydroxycholecalciferol associated with the sedimented plasma fractions. The uptake of [ 3 H]vitamin D 3 from plasma, LDL, or HDL was studied in cultured human cells; uptake by normal fibroblasts was greatest from LDL and least from plasma. The cellular association of vitamin D 3 was time, concentration, and temperature dependent. At a concentration of 50 μg LDL/ml of medium, the uptake of [ 3 H]vitamin D 3 from LDL at 37 0 C was rapid and reached a maximum at approximately 4 hr; it was slower from HDL but continued to increase slowly up to 24 hr. The significance of these in vitro findings is uncertain since much of the vitamin D 3 absorbed from the intestine reportedly associates with chylomicrons and is rapidly taken up by the liver

Lipoprotein(a) accelerates atherosclerosis in uremic mice

DEFF Research Database (Denmark)

Pedersen, Tanja X; McCormick, Sally P; Tsimikas, Sotirios

2010-01-01

Uremic patients have increased plasma lipoprotein(a) [Lp(a)] levels and elevated risk of cardiovascular disease. Lp(a) is a subfraction of LDL, where apolipoprotein(a) [apo(a)] is disulfide bound to apolipoprotein B-100 (apoB). Lp(a) binds oxidized phospholipids (OxPL), and uremia increases lipop...

Native High Density Lipoproteins (HDL Interfere with Platelet Activation Induced by Oxidized Low Density Lipoproteins (OxLDL

Directory of Open Access Journals (Sweden)

Ivo Volf

2013-05-01

Full Text Available Platelets and lipoproteins play a crucial role in atherogenesis, in part by their ability to modulate inflammation and oxidative stress. While oxidized low density lipoproteins (OxLDL play a central role in the development of this disease, high density lipoproteins (HDL represent an atheroprotective factor of utmost importance. As platelet function is remarkably sensitive to the influence of plasma lipoproteins, it was the aim of this study to clarify if HDL are able to counteract the stimulating effects of OxLDL with special emphasis on aspects of platelet function that are relevant to inflammation. Therefore, HDL were tested for their ability to interfere with pro-thrombotic and pro-inflammatory aspects of platelet function. We are able to show that HDL significantly impaired OxLDL-induced platelet aggregation and adhesion. In gel-filtered platelets, HDL decreased both the formation of reactive oxygen species and CD40L expression. Furthermore, HDL strongly interfered with OxLDL-induced formation of platelet-neutrophil aggregates in whole blood, suggesting that platelets represent a relevant and sensitive target for HDL. The finding that HDL effectively competed with the binding of OxLDL to the platelet surface might contribute to their atheroprotective and antithrombotic properties.

Temporal development of the plasma composition of a pulsed aluminum plasma stream in the presence of oxygen

International Nuclear Information System (INIS)

Schneider, J.M.; Anders, A.; Brown, I.G.; Hjoervarsson, B.; Hultman, L.

1999-01-01

We describe the temporal development of the plasma composition of pulsed aluminum plasma streams at various oxygen pressures. The plasma was formed with a vacuum arc plasma source and the time resolved plasma composition was measured with time-of-flight charge-to-mass spectrometry. The temporal development of the plasma composition as well as the Al average ion charge state was found to be a strong function of the oxygen pressure. Oxygen and hydrogen concentrations of up to 0.36 and 0.32, respectively, were found in the first 50 μs of the pulse at oxygen pressures of ≥5x10 -5 Torr. The average charge state of aluminum ions was found to vary from +1.2 to +2.5 depending on the oxygen pressure and the time elapsed after ignition of the arc. These results are of fundamental importance for the understanding of the evolution of the composition (through the plasma composition) and microstructure (through the Al ion flux energy) of alumina thin films produced by pulsed, reactive aluminum plasmas. copyright 1999 American Institute of Physics

Effect of apolipoprotein M on high density lipoprotein metabolism and atherosclerosis in low density lipoprotein receptor knock-out mice

DEFF Research Database (Denmark)

Christoffersen, Christina; Jauhiainen, Matti; Moser, Markus

2008-01-01

To investigate the role of apoM in high density lipoprotein (HDL) metabolism and atherogenesis, we generated human apoM transgenic (apoM-Tg) and apoM-deficient (apoM(-/-)) mice. Plasma apoM was predominantly associated with 10-12-nm alpha-migrating HDL particles. Human apoM overexpression (11-fol...

Effect of high density lipoproteins on permeability of rabbit aorta to low density lipoproteins

International Nuclear Information System (INIS)

Klimov, A.N.; Popov, V.A.; Nagornev, V.A.; Pleskov, V.M.

1985-01-01

A study was made on the effect of high density lipoproteins (HDL) on the permeability of rabbit aorta to low density lipoproteins (LDL) after intravenous administration of human HDL and human ( 125 I)LDL to normal and hypercholesterolemic rabbits. Evaluation of radioactivity in plasma and aorta has shown that the administration of a large dose of HDL decreased the aorta permeability rate for ( 125 I)LDL on an average by 19% in normal rabbits, and by 45% in rabbits with moderate hypercholesterolemia. A historadiographic study showed that HDL also decreased the vessel wall permeability to ( 125 I)LDL in normal and particularly in hypercholesterolemic animals. The suggestion was made that HDL at very high molar concentration can hamper LDL transportation through the intact endothelial layer into the intima due to the ability of HDL to compete with LDL in sites of low affinity on the surface of endothelial cells. (author)

Alterations in plasma lipoproteins and apolipoproteins before the age of 40 in heterozygotes for lipoprotein lipase deficiency

NARCIS (Netherlands)

Bijvoet, S.; Gagné, S. E.; Moorjani, S.; Gagné, C.; Henderson, H. E.; Fruchart, J. C.; Dallongeville, J.; Alaupovic, P.; Prins, M. [=Martin H.; Kastelein, J. J.; Hayden, M. R.

1996-01-01

We have assessed the expression of heterozygosity for lipoprotein lipase (LPL) deficiency by studying a single large French Canadian family comprising 92 persons including 21 carriers of the catalytically defective P207L mutation. Phenotypic changes distinguishing heterozygotes from controls were

Recent advances in lipoprotein and atherosclerosis: A nutrigenomic approach

OpenAIRE

López, Sergio; Ortega, Almudena; Varela, Lourdes; Bermúdez, Beatriz; Muriana, Francisco JG; Abia, Rocío

2009-01-01

Atherosclerosis is a disease in which multiple factors contribute to the degeneration of the vascular wall. Many risk factors have been identified as having influence on the progression of atherosclerosis among them, the type of diet. Multifactorial interaction among lipoproteins, vascular wall cells, and inflammatory mediators has been recognised as the basis of atherogenesis. Dietary intake affects lipoprotein concentration and composition providing risk or protection at several stages of a...

Lipoproteins tethered dendrimeric nanoconstructs for effective targeting to cancer cells

Science.gov (United States)

Jain, Anupriya; Jain, Keerti; Mehra, Neelesh Kumar; Jain, N. K.

2013-10-01

In the present investigation, poly (propylene imine) dendrimers up to fifth generation (PPI G5.0) were synthesized using ethylene diamine and acrylonitrile. Lipoproteins (high-density lipoprotein; HDL and low-density lipoprotein; LDL) were isolated from human plasma by discontinuous density gradient ultracentrifugation, characterized and tethered to G5.0 PPI dendrimers to construct LDL- and HDL-conjugated dendrimeric nanoconstructs for tumor-specific delivery of docetaxel. Developed formulations showed sustained release characteristics in in vitro drug release and in vivo pharmacokinetic studies. The cancer targeting potential of lipoprotein coupled dendrimers was investigated by ex vivo cytotoxicity and cell uptake studies using human hepatocellular carcinoma cell lines (HepG2 cells) and biodistribution studies in albino rats of Sprague-Dawley strain. Lipoprotein anchored dendrimeric nanoconstructs showed significant uptake by cancer cells as well as higher biodistribution of docetaxel to liver and spleen. It is concluded that these precisely synthesized engineered dendrimeric nanoconstructs could serve as promising drug carrier for fighting with the fatal disease, i.e., cancer, attributed to their defined targeting and therapeutic potential.

Lipoproteins tethered dendrimeric nanoconstructs for effective targeting to cancer cells

Energy Technology Data Exchange (ETDEWEB)

Jain, Anupriya; Jain, Keerti, E-mail: keertijain02@gmail.com; Mehra, Neelesh Kumar, E-mail: neelesh81mph@gmail.com; Jain, N. K., E-mail: dr.jnarendr@gmail.com [Dr. H. S. Gour University, Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences (India)

2013-10-15

In the present investigation, poly (propylene imine) dendrimers up to fifth generation (PPI G5.0) were synthesized using ethylene diamine and acrylonitrile. Lipoproteins (high-density lipoprotein; HDL and low-density lipoprotein; LDL) were isolated from human plasma by discontinuous density gradient ultracentrifugation, characterized and tethered to G5.0 PPI dendrimers to construct LDL- and HDL-conjugated dendrimeric nanoconstructs for tumor-specific delivery of docetaxel. Developed formulations showed sustained release characteristics in in vitro drug release and in vivo pharmacokinetic studies. The cancer targeting potential of lipoprotein coupled dendrimers was investigated by ex vivo cytotoxicity and cell uptake studies using human hepatocellular carcinoma cell lines (HepG2 cells) and biodistribution studies in albino rats of Sprague-Dawley strain. Lipoprotein anchored dendrimeric nanoconstructs showed significant uptake by cancer cells as well as higher biodistribution of docetaxel to liver and spleen. It is concluded that these precisely synthesized engineered dendrimeric nanoconstructs could serve as promising drug carrier for fighting with the fatal disease, i.e., cancer, attributed to their defined targeting and therapeutic potential.

High-density lipoprotein modulates glucose metabolism in patients with type 2 diabetes mellitus

DEFF Research Database (Denmark)

Drew, Brian G; Duffy, Stephen J; Formosa, Melissa F

2009-01-01

BACKGROUND: Low plasma high-density lipoprotein (HDL) is associated with elevated cardiovascular risk and aspects of the metabolic syndrome. We hypothesized that HDL modulates glucose metabolism via elevation of plasma insulin and through activation of the key metabolic regulatory enzyme, AMP...

Streptozotocin-Treated High Fat Fed Mice: A New Type 2 Diabetes Model Used to Study Canagliflozin-Induced Alterations in Lipids and Lipoproteins.

Science.gov (United States)

Yu, Tian; Sungelo, Mitchell J; Goldberg, Ira J; Wang, Hong; Eckel, Robert H

2017-05-01

The pharmacological effects of type 2 diabetes (T2DM) medications on lipoprotein metabolism are difficult to assess in preclinical models because those created failure to replicate the human condition in which insulin deficiency is superimposed on obesity-related insulin resistance. To create a better model, we fed mice with high fat (HF) diet and treated the animals with low dose streptozotocin (STZ) to mimic T2DM. We used this model to evaluate the effects of canagliflozin (CANA), a drug that reduces plasma glucose by inhibiting the sodium-glucose transporter 2 (SGLT2), which mediates ~90% of renal glucose reabsorption] on lipid and lipoprotein metabolism. After 6 weeks of CANA (30 mg/kg/day) treatment, the increase in total plasma cholesterol in HF-STZ diabetic mice was reversed, but plasma triglycerides were not affected. Lipoprotein fractionation and cholesterol distribution analysis showed that CANA kept HDL-Cholesterol, LDL-Cholesterol, and IDL-Cholesterol levels steady while these lipoprotein species were increased in placebo- and insulin-treated control groups. CANA treatment of HF-STZ mice reduced post-heparin plasma lipoprotein lipase (LPL) activity at 2 (-40%) and 5 (-30%) weeks compared to placebo. Tissue-specific LPL activity following CANA treatment showed similar reduction. In summary, CANA prevented the total cholesterol increase in HF-STZ mice without effects on plasma lipids or lipoproteins, but did decrease LPL, implying a potential role of LPL-dependent lipoprotein metabolism in CANA action. These effects did not recapitulate the effect of SGLT2 inhibitors on lipids and lipoproteins in human, suggesting that a better murine T2DM model (such as the ApoB100 humanized CETP-overexpressing mouse) is needed next. © Georg Thieme Verlag KG Stuttgart · New York.

Lipoproteins and lipoprotein mimetics for imaging and drug delivery.

Science.gov (United States)

Thaxton, C Shad; Rink, Jonathan S; Naha, Pratap C; Cormode, David P

2016-11-15

Lipoproteins are a set of natural nanoparticles whose main role is the transport of fats within the body. While much work has been done to develop synthetic nanocarriers to deliver drugs or contrast media, natural nanoparticles such as lipoproteins represent appealing alternatives. Lipoproteins are biocompatible, biodegradable, non-immunogenic and are naturally targeted to some disease sites. Lipoproteins can be modified to act as contrast agents in many ways, such as by insertion of gold cores to provide contrast for computed tomography. They can be loaded with drugs, nucleic acids, photosensitizers or boron to act as therapeutics. Attachment of ligands can re-route lipoproteins to new targets. These attributes render lipoproteins attractive and versatile delivery vehicles. In this review we will provide background on lipoproteins, then survey their roles as contrast agents, in drug and nucleic acid delivery, as well as in photodynamic therapy and boron neutron capture therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Changes in remnant and high-density lipoproteins associated with hormone therapy and progression of coronary artery disease in postmenopausal women

Science.gov (United States)

The effect of hormone therapy (HT) on the plasma concentration of remnant lipoprotein cholesterol (RLP-C) and high density lipoprotein (HDL) subpopulations and the contribution of HT-related changes in these lipoproteins to the progression of coronary heart disease (CHD) were examined in 256 postmen...

Lipoprotein (a) Management: Lifestyle and Hormones.

Science.gov (United States)

Garcia-Rios, Antonio; Leon-Acuna, Ana; Lopez-Miranda, Jose; Perez-Martinez, Pablo

2017-01-01

Cardiovascular disease (CVD) continues to be the first cause of mortality in developed countries. Moreover, far from diminishing, the cardiovascular risk factors leading towards the development of CVD are on the rise. Therefore, the preventive and therapeutic management which is currently in place is clearly not enough to stop this pandemic. In this context, a major resurgence in interest in lipoprotein (a) [Lp(a)] has occurred in light of its association with CVD. This series aims to review the basic and clinical aspects of Lp(a) biology. Specifically, the present review considers the current situation regarding the influence of lifestyle, hormones and other physiological or pathological conditions on Lp(a) plasma concentrations which might mitigate the harmful effects of this lipoprotein. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Effect of the Composition of Infusion Media on the Blood Lipoprotein Profile in the Treatment of Gestosis

Directory of Open Access Journals (Sweden)

L. N. Shcherbakova

2009-01-01

Full Text Available Objective: to study whether reamberin and hydroxyethyl starch may be used to correct dyslipoproteinemia in gestosis. Subjects and methods: Twenty-two patients with early postoperative gestosis were examined. Group 1 patients (n=8 received the standard treatment. In addition to the standard treatment, Group 2 patients (n=7 were given 6% hydroxyethyl starch solution infusion at concentrations of 5-6 ml/kg body weight at a rate of 3 ml/ml. Just after hydroxyethyl starch infusion, Group 3 patients (n=7 were additionally injected 1.5% reamberin by the above scheme. The results of examinations were compared with the data obtained on examination of 8 puerperas after pregnancy and normal delivery (Group 4. The plasma concentration of triglycerides, total cholesterol (TC, and the cholesterols of high-density lipoprotein (HDL, low-density lipoprotein (LDL, and very low-density lipoprotein (VLDL were measured. Results and discussion. All the puerperas with gestosis were found to have hypertriglyceridemia and elevated levels of VLDL cholesterol with decreased concentrations of HDL cholesterol. The moderately higher levels of triglycerides and TC were also observed in patients without gestosis. Hydroxyethyl starch lowered the concentration of triglycerides by postpartum days 3—4. When hydroxyethyl starch was used in combination with reamberin, there was a significant reduction in the concentrations of triglycerides and VLDL and LDL cholesterols and a substantial rise in the level of HDL cholesterol. By postpartum days 3 and 4, Group 1 showed a considerable increase in the atherogenicity coefficient, which was significant as compared with the baseline level. Hydroxyethyl starch alone prevented an increase in the atherogenici-ty coefficient while its use in combination with reamberin significantly lowered this index and normalized it by postpartum days 3—4. Conclusion. Hydroxyethyl starch alone and in combination with reamberin shows an antiatherogenic

The effect of platelet-rich plasma on composite graft survival.

Science.gov (United States)

Jeon, Yeo Reum; Kang, Eun Hye; Yang, Chae Eun; Yun, In Sik; Lee, Won Jai; Lew, Dae Hyun

2014-08-01

Composite grafts are suitable for facial reconstruction because of good color matching, low donor-site morbidity, acceptable texture, and easy surgical techniques. However, their use is limited to small defects and by unpredictable survival rates. As platelet-rich plasma contains large numbers of growth factors and has been widely used for tissue regeneration, this study aimed to investigate platelet-rich plasma as an adjuvant to enhance composite graft survival. Twenty New Zealand White rabbits were used, and chondrocutaneous composite grafts were applied to their ears. The grafts were then returned to their original positions after rotation to block the original circulation from the base of the graft. Each of the individual ears was assigned randomly into one of two groups: experimental (n=20; platelet-rich plasma group) or control (n=20; control group). The surrounding skin of the composite graft was injected with either 1.0 ml of platelet-rich plasma derived from autologous whole blood in the platelet-rich plasma group or normal saline in the control group. Graft survival, cutaneous blood flow, CD31-stained vessels, and vascular endothelial growth factor protein levels were examined. Twelve days after surgery, graft viability in the platelet-rich plasma group was higher than in the control group. Blood perfusion was also higher in the platelet-rich plasma group. Compared with the control group, the number of CD31 blood vessels and vascular endothelial growth factor expression levels were significantly increased in the platelet-rich plasma group. The authors' results suggest that platelet-rich plasma restores the perfusion of composite grafts by enhancing revascularization and may exert therapeutic effects on the survival of composite grafts.

The effect of fish oil enriched margarine on plasma lipids, low density lipoprotein particle composition, size and susceptibility to oxidation

DEFF Research Database (Denmark)

Nielsen, Nina Skall; Marckmann, Peter; Høy, Carl-Erik

1998-01-01

We investigated the effect of incorporating n-3 polyunsaturated fatty acids (PUFAs) into the diet on the lipid-class composition of LDLs, their size, and their susceptibility to oxidation. Forty-seven healthy volunteers incorporated 30 g sunflower-oil (SO) margarine/d into their habitual diet...... during a 3-wk run-in period and then used either SQ or a fish-oil-enriched sunflower oil (FO) margarine for the following 4 wk. Plasma concentrations of total cholesterol, triacylglycerols, HDL cholesterol, LDL cholesterol, and apolipoproteins A-I and B did not differ significantly between the groups...... to 86 min, P = 0.003) and lower maximum rate of oxidation (from 10.5 to 10.2 nmol.mg(-1).min(-1), P = 0.003) after intake of the FO margarine. The results indicate that consumption of the FO compared with the SO margarine had no effect on LDL size and lipid composition and led to minor changes in LDL...

Structural studies on lipoprotein lipase

International Nuclear Information System (INIS)

Socorro, L.

1985-01-01

The structure of lipoprotein lipase is not known. The lack of information on its primary sequence has been due to the inability of preparing it in homogeneous and stable form. This research has focused on the structural characterization of lipoprotein lipase. The first approach taken was to develop a purification method using bovine milk and affinity chromatography on heparin-Sepharose. The protein obtained was a heterogeneous peak with the activity shifted towards the trailing edge fractions. These fractions only presented a 55 Kdalton band on polyacrylamide gel electrophoresis. Monoclonal antibodies against this band detected an endogenous, phenyl methane sulfonyl fluoride-sensitive protease responsible for the presence of lower molecular weight fragments. The second approach was to label the lipoprotein lipase with a radioactive, active site, directed probe. After incubation and affinity chromatography a complex [ 3 H]inhibitor enzyme was isolated with a stoichiometry of 1.00 +/- 0.2. The complex was digested with CNBr and the insoluble peptides at low ionic strength (>90% [ 3 H]dpm) were used for further purification. Differential extraction of the [ 3 H]-peptide, digestion with S. aureus V8 protease, and high performance liquid chromatography yielded a hexapeptide with a composition consistent with the consensus sequence of the active site peptides of many serine-esterase. This and the kinetic data imply this being the mechanism of action for lipoprotein lipase

Disposition of 14C-β-carotene following delivery with autologous triacylglyceride-rich lipoproteins

International Nuclear Information System (INIS)

Dueker, Stephen R.; Le Thuy Vuong; Faulkner, Brian; Buchholz, Bruce A.; Vogel, John S.

2007-01-01

Following ingestion, a fraction of β-carotene is cleaved into vitamin A in the intestine, while another is absorbed intact and distributed among tissues and organs. The extent to which this absorbed β-carotene serves as a source of vitamin A is unknown in vivo. In the present study we use the attomole sensitivity of accelerator mass spectrometry (AMS) for 14 C to quantify the disposition of 14 C-β-carotene (930 ng; 60.4 nCi of activity) after intravenous injection with an autologous triacylglyceride-rich lipoprotein fraction in a single volunteer. Total 14 C was quantified in serial plasma samples and also in triglyceride-rich, and low density lipoprotein, subfractions. The appearance of 14 C-retinol, the circulating form of vitamin A in plasma, was determined by chromatographic separation of plasma retinol extracts prior to AMS analysis. The data showed that 14 C concentrations rapidly decayed within the triglyceride-rich lipoprotein fractions after injection, whereas low density lipoprotein 14 C began a significant rise in 14 C 5 h post dose. Plasma 14 C-retinol also appeared at 5 h post dose and its concentrations were maintained above baseline for >88 days. Based upon comparisons of 14 C-retinol concentrations following an earlier study with orally dosed 14 C-β-carotene, a molar vitamin A value of the absorbed β-carotene of 0.19 was derived, meaning that 1 mole of absorbed β-carotene provides 0.19 moles of vitamin A. This is the first study to show that infused β-carotene contributes to the vitamin A economy in humans in vivo

Lipoprotein(a)

DEFF Research Database (Denmark)

Langsted, Anne; Kamstrup, Pia R; Nordestgaard, Børge G

2014-01-01

OBJECTIVE: There are no recommendations in guidelines on measuring lipoprotein(a) in the fasting or nonfasting state, or on the influence of inflammation. We tested the hypotheses that lipoprotein(a) levels change only minimally in response to normal food intake, and to inflammation. Also, we...... tested whether normal food intake or inflammation influenced lipoprotein(a)'s ability to predict ischemic heart disease. METHODS: We studied 34 829 individuals from the Danish general population using the Copenhagen General Population Study and the Copenhagen City Heart Study. RESULTS: Lipoprotein......(a) levels did not change in response to normal food intake: median fasting levels were 17.3 mg/dL, while median levels at 3-4 h since last meal were 19.4 mg/dL(p = 0.38). Lipoprotein(a) levels increased minimally with increasing levels of C-reactive protein(CRP): median lipoprotein(a) levels at CRP

HfC plasma coating of C/C composites

International Nuclear Information System (INIS)

Boncoeur, M.; Schnedecker, G.; Lulewicz, J.D.

1992-01-01

The surface properties of C/C composites such as hardness and corrosion or erosion resistance can be modified by a ceramic coating applied by plasma torch. The technique of plasma spraying in controlled temperature and atmosphere, that was developed and patented by the CEA, makes it possible to apply coatings to the majority of metals and ceramics without affecting the characteristics of the composite. An example of hard deposit of HfC on a C/C composite is described. The characteristics of the deposit and of the bonding with the C/C composite were studied before and after a heat treatment under vacuum for 2 hours at 1000 C. 2 refs

Layered plasma polymer composite membranes

Science.gov (United States)

Babcock, Walter C.

1994-01-01

Layered plasma polymer composite fluid separation membranes are disclosed, which comprise alternating selective and permeable layers for a total of at least 2n layers, where n is .gtoreq.2 and is the number of selective layers.

Optical coherence tomography in quantifying the permeation of human plasma lipoproteins in vascular tissues

Science.gov (United States)

Ghosn, M. G.; Mashiatulla, M.; Tuchin, V. V.; Morrisett, J. D.; Larin, K. V.

2012-03-01

Atherosclerosis is the most common underlying cause of vascular disease, occurring in multiple arterial beds including the carotid, coronary, and femoral arteries. Atherosclerosis is an inflammatory process occurring in arterial tissue, involving the subintimal accumulation of low-density lipoproteins (LDL). Little is known about the rates at which these accumulations occur. Measurements of the permeability rate of LDL, and other lipoproteins such as high-density lipoprotein (HDL) and very low-density lipoprotein (VLDL), could help gain a better understanding of the mechanisms involved in the development of atherosclerotic lesions. The permeation of VLDL, LDL, HDL, and glucose was monitored and quantified in normal and diseased human carotid endarterectomy tissues at 20°C and 37°C using optical coherence tomography (OCT). The rates for LDL permeation through normal tissue at 20°C was (3.16 +/- 0.37) × 10-5 cm/sec and at 37°C was (4.77 +/- 0.48) × 10-5 cm/sec, significantly greater (plipoproteins.

A high-density lipoprotein-mediated drug delivery system.

Science.gov (United States)

Mo, Zhong-Cheng; Ren, Kun; Liu, Xing; Tang, Zhen-Li; Yi, Guang-Hui

2016-11-15

High-density lipoprotein (HDL) is a comparatively dense and small lipoprotein that can carry lipids as a multifunctional aggregate in plasma. Several studies have shown that increasing the levels or improving the functionality of HDL is a promising target for treating a wide variety of diseases. Among lipoproteins, HDL particles possess unique physicochemical properties, including naturally synthesized physiological components, amphipathic apolipoproteins, lipid-loading and hydrophobic agent-incorporating characteristics, specific protein-protein interactions, heterogeneity, nanoparticles, and smaller size. Recently, the feasibility and superiority of using HDL particles as drug delivery vehicles have been of great interest. In this review, we summarize the structure, constituents, biogenesis, remodeling, and reconstitution of HDL drug delivery systems, focusing on their delivery capability, characteristics, applications, manufacturing, and drug-loading and drug-targeting characteristics. Finally, the future prospects are presented regarding the clinical application and challenges of using HDL as a pharmacodelivery carrier. Copyright © 2016 Elsevier B.V. All rights reserved.

Sphingolipids and Lipoproteins in Health and Metabolic Disorders.

Science.gov (United States)

Iqbal, Jahangir; Walsh, Meghan T; Hammad, Samar M; Hussain, M Mahmood

2017-07-01

Sphingolipids are structurally and functionally diverse molecules with significant physiologic functions and are found associated with cellular membranes and plasma lipoproteins. The cellular and plasma concentrations of sphingolipids are altered in several metabolic disorders and may serve as prognostic and diagnostic markers. Here we discuss various sphingolipid transport mechanisms and highlight how changes in cellular and plasma sphingolipid levels contribute to cardiovascular disease, obesity, diabetes, insulin resistance, and nonalcoholic fatty liver disease (NAFLD). Understanding of the mechanisms involved in intracellular transport, secretion, and extracellular transport may provide novel information that might be amenable to therapeutic targeting for the treatment of various metabolic disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

Remnant lipoproteins

DEFF Research Database (Denmark)

Varbo, Anette; Nordestgaard, Børge G.

2017-01-01

Purpose of review: To review recent advances in the field of remnant lipoproteins and remnant cholesterol with a focus on cardiovascular disease risk. Recent findings: In line with previous years' research, current observational, genetic, and mechanistic studies find remnant lipoproteins (defined...... of cardiovascular disease risk reduction through remnant lipoprotein lowering are under way....

Plasma penetration depth and mechanical properties of atmospheric plasma-treated 3D aramid woven composites

International Nuclear Information System (INIS)

Chen, X.; Yao, L.; Xue, J.; Zhao, D.; Lan, Y.; Qian, X.; Wang, C.X.; Qiu, Y.

2008-01-01

Three-dimensional aramid woven fabrics were treated with atmospheric pressure plasmas, on one side or both sides to determine the plasma penetration depth in the 3D fabrics and the influences on final composite mechanical properties. The properties of the fibers from different layers of the single side treated fabrics, including surface morphology, chemical composition, wettability and adhesion properties were investigated using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), contact angle measurement and microbond tests. Meanwhile, flexural properties of the composites reinforced with the fabrics untreated and treated on both sides were compared using three-point bending tests. The results showed that the fibers from the outer most surface layer of the fabric had a significant improvement in their surface roughness, chemical bonding, wettability and adhesion properties after plasma treatment; the treatment effect gradually diminished for the fibers in the inner layers. In the third layer, the fiber properties remained approximately the same to those of the control. In addition, three-point bending tests indicated that the 3D aramid composite had an increase of 11% in flexural strength and 12% in flexural modulus after the plasma treatment. These results indicate that composite mechanical properties can be improved by the direct fabric treatment instead of fiber treatment with plasmas if the fabric is less than four layers thick

Plasma lipoproteins in familial dysbetalipoproteinemia associated with apolipoproteins E2 (Arg158 -->Cys), E3-Leiden, and E2 (Lys146-->Gln), and effects of treatment with simvastatin

NARCIS (Netherlands)

Zhao, S.P.; Smelt, A.H.; Maagdenberg, A.M. van den; Tol, A. van; Vroom T.F.; Gevers Leuven, J.A.; Frants, R.R.; Havekes, L.M.; Laarse, A. van der; Hooft, F.M. van 't

1994-01-01

Using a density-gradient ultracentrifugation technique, we analyzed in detail the plasma lipoprotein profiles of 18 patients with familial dysbetalipoproteinemia (FD) who had apolipoprotein (apo) E2(Arg158-->Cys) homozygosity (the E2-158 variant, n = 6), apoE3-Leiden heterozygosity (the E3-Leiden

The age dependency of gene expression for plasma lipids, lipoproteins, and apolipoproteins

Energy Technology Data Exchange (ETDEWEB)

Snieder, H.; Doornen, L.J.P. van; Boomsma, D.I. [Vrije Universiteit, Amsterdam (Netherlands)

1997-03-01

The aim of this study was to investigate and disentangle the genetic and nongenetic causes of stability and change in lipids and (apo)lipoproteins that occur during the lifespan. Total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), and lipoprotein(a) (Lp[a]) were measured in a group of 160 middle-aged parents and their twin offspring (first project) and in a group of 203 middle-aged twin pairs (second project). Combining the data of both projects enabled the estimation of the extent to which measured lipid parameters are influenced by different genes in adolescence and adulthood. To that end, an extended quantitative genetic model was specified, which allowed the estimation of heritabilities for each sex and generation separately. Heritabilities were similar for both sexes and both generations. Larger variances in the parental generation could be ascribed to proportional increases in both unique environmental and additive genetic variance from childhood to adulthood, which led to similar heritability estimates in adolescent and middle-aged twins. Although the magnitudes of heritabilities were similar across generations, results showed that, for total cholesterol, triglycerides, HDL, and LDL, partly different genes are expressed in adolescence compared to adulthood. For triglycerides, only 46% of the genetic variance was common to both age groups; for total cholesterol this was 80%. Intermediate values were found for HDL (66%) and LDL (76%). For ApoA1, ApoB, and Lp(a), the same genes seem to act in both generations. 56 refs., 2 figs., 5 tabs.

Measurement of apolipoprotein B radioactivity in whole blood plasma by precipitation with isopropanol

International Nuclear Information System (INIS)

Yamada, N.; Havel, R.J.

1986-01-01

A method to measure apolipoprotein B radioactivity in whole blood plasma is described that is suitable for routine use in kinetic experiments in vivo. Radiolabeled apolipoprotein B is precipitated from plasma diluted 15- to 30-fold in the presence of carrier low density lipoproteins by 50% isopropanol. The amount of radioiodine in apoB is estimated from the difference between total radioiodine concentration in whole plasma and the fraction soluble in 50% isopropanol. Addition of up to 100 microliters of plasma to radioiodinated lipoproteins did not alter the percent of radioiodine precipitated in 1500 microliters of 50% isopropanol. The percent of radioiodine precipitated by isopropanol 3 min after intravenous injection of homologous radioiodinated very low density lipoproteins, intermediate density lipoproteins, and low density lipoproteins into rabbits was almost identical to that in the injected lipoproteins (y = 1.009 X +/- 0.462; r = 0.997)

Sort1, encoded by the cardiovascular risk locus 1p13.3, is a regulator of hepatic lipoprotein export

DEFF Research Database (Denmark)

Kjølby, Mads Fuglsang; Andersen, Olav Michael; Breiderhoff, Tilman

2010-01-01

of lipoproteins from the liver and ameliorates hypercholesterolemia and atherosclerotic lesion formation in LDL receptor-deficient animals. In contrast, sortilin overexpression stimulates hepatic release of lipoproteins and increases plasma LDL levels. Our data have uncovered a regulatory pathway in hepatic...... lipoprotein export and suggest a molecular explanation for the cardiovascular risk being associated with 1p13.3. Udgivelsesdato: september 8...

Metabolism of triglyceride-rich nascent rat hepatic high density lipoproteins

International Nuclear Information System (INIS)

Winkler, K.E.; Marsh, J.B.

1989-01-01

Nascent high density lipoprotein (HDL) and nascent very low density lipoprotein (VLDL) were isolated from rat livers that had been perfused with [3H]glycerol to label the triglyceride. When injected into intact rats, the labeled HDL-triglyceride disappeared as rapidly as the VLDL-triglyceride, with only 10% of the injected label remaining in the plasma after 30 min. The protein moiety of nascent HDL was labeled with [35S]methionine in a similar fashion and the labeled nascent HDL was separated into nonretained (NR) and retained (R) fractions by heparin-Sepharose affinity chromatography. When injected into rats, 55% of the injected label in nascent fraction NR and 72% of that in nascent fraction R was recovered from plasma at 30 min, compared to only 10% of the triglyceride label from unfractionated nascent HDL, indicating dissociation of triglyceride and apolipoprotein clearance. The plasma decay curves for both triglyceride and protein were biexponential. By 5 min, 15% of the 35S label remaining in plasma represented apoE and apoC that had been transferred from nascent HDL fractions NR and R to the d less than 1.063 g/ml fraction of plasma. Plasma HDL was labeled in vivo with [35S]methionine, separated into fractions NR and R, and the clearance of the two plasma HDL fractions was compared with that of the corresponding nascent HDL fractions. Except for a faster rate of removal of the nascent HDL fractions during the first 5 min, the serum decay curves were very similar

Acetaldehyde binding increases the catabolism of rat serum low-density lipoproteins

International Nuclear Information System (INIS)

Savolainen, M.J.; Baraona, E.; Lieber, C.S.

1987-01-01

Acetaldehyde was found to form adducts with rat serum lipoproteins. The binding of [ 14 C]acetaldehyde to lipoproteins was studied at low concentrations which are known to exist during ethanol oxidation. The amount of lipoprotein adducts was a linear function of acetaldehyde concentration up to 250 μM. Incubation of rat plasma low-density lipoproteins (LDL) with 200 μM acetaldehyde increased the disappearance rate of the 3 H-label from the cholesterol ester moiety of LDL injected into normal rats. The data show that even low concentrations of acetaldehyde are capable of affecting LDL metabolism. These findings may provide an explanation for the low concentrations of serum LDL in alcoholics. The alcohol-induced hyperlipidemia includes either a lack of increase or a decrease in the low-density lipoprotein (LDL) concentration, but the underlying mechanism is not known. It has been shown previously, that the acetylation of lysine residues of LDL apoprotein (apoB) by acetanhydride leads to rapid uptake of LDL particles by macrophages through a non-LDL receptor pathway. Since acetaldehyde, the first toxic metabolite of ethanol, is a chemically reactive compound capable of binding to proteins, they tested whether acetaldehyde forms adducts with serum lipoproteins and subsequently alters the catabolism of LDL. 19 references, 2 figures, 1 table

Preparation of 19-iodocholestrol labelled with I-125 and its study as a 'tracer' of plasma lipoprotein

International Nuclear Information System (INIS)

Rodriquez Barquero, L.

1988-01-01

A technique of synthesis of the 19-iodocholesterol labelled with I-125, modified in some steps from other methods published previously, is described. We have obtained a product with high chemical (96%) and radiochemical (99,9%) purities. The yield was higher and the time necessary to prepare it was lower than other methods reported. The study of thermal and radiolytic stability showed that the 19-iodocholesterol-I-125 was not broken by autoradiolysis whereas the I-125 was separated from the molecule when the temperature was increased. The use of this 19-iodocholesterol-I-125 as a tracer of cholesterol of plasma lipoprotein showed some properties of LCAT and CETP and also showed the different capacity of VLDL and LDL to transport cholesteryl esters. (author) 105 refs

Effect of platelet activating factor on endothelial permeability to plasma macromolecules

International Nuclear Information System (INIS)

Handley, D.A.; Arbeeny, C.M.; Lee, M.L.; Van Valen, R.G.; Saunders, R.N.

1984-01-01

The effect of intrajugular administration of platelet activating factor (PAF-C16) on vascular permeability was examined in the guinea pig. To examine the loss of selective endothelial permeability, the extravasative effect of PAF was assessed by monitoring hemoconcentration and the plasma loss of 125 I-albumin (6.7 nm), 125 I-low density lipoproteins (22.0 nm) or 125 I-very low density lipoproteins (62.1 nm). Extravasation was dose-dependent and began 1 min after PAF administration, continuing for 5-7 min. During extravasation, there was no evidence for selective plasma retention of any of the labeled plasma tracers, as measured by plasma radioactivity. These results suggest that PAF-induced extravasation is dose-dependent, with increases in vascular permeability sufficient to permit similar plasma efflux rates of albumin, low density lipoproteins and very low density lipoproteins

Lipoprotein complex formation

International Nuclear Information System (INIS)

Musliner, T.A.; Krauss, R.M.

1987-01-01

Transfers of lipids and proteins between different lipoproteins are known to occur in the course of their metabolism. It is likely that these transfers take place during transient physical associations between lipoprotein particles, but the nature and chemical basis for such interactions are poorly understood. The fact that lipid and apolipoprotein movements are particularly prevalent during the intravascular lipolysis of triglyceride-rich lipoproteins suggested to us that lipolysis products accumulating on these particles might promote physical binding with other lipoproteins. To test this hypothesis, we studied interactions between very low-density, low density, and high-density lipoproteins in the setting of partial lipolysis by bovine milk lipoprotein lipase in the presence of limited unesterified fatty acid acceptor. 2 figs., 1 tab

Plasma metabolism of apolipoprotein A-IV in humans

International Nuclear Information System (INIS)

Ghiselli, G.; Krishnan, S.; Beigel, Y.; Gotto, A.M. Jr.

1986-01-01

As assessed by molecular sieve chromatography and quantitation by a specific radioimmunoassay, apoA-IV is associated in plasma with the triglyceride-rich lipoproteins, to a high density lipoprotein (HDL) subfraction of smaller size than HDL3, and to the plasma lipoprotein-free fraction (LFF). In this study, the turnover of apoA-IV associated to the triglyceride-rich lipoproteins, HDL and LFF was investigated in vivo in normal volunteers. Human apoA-IV isolated from the thoracic duct lymph chylomicrons was radioiodinated and incubated with plasma withdrawn from normal volunteers after a fatty meal. Radioiodinated apoA-IV-labeled triglyceride-rich lipoproteins, HDL, and LFF were then isolated by chromatography on an AcA 34 column. Shortly after the injection of the radioiodinated apoA-IV-labeled triglyceride-rich lipoproteins, most of the radioactivity could be recovered in the HDL and LFF column fractions. On the other hand, when radioiodinated apoA-IV-labeled HDL or LFF were injected, the radioactivity remained with the originally injected fractions at all times. The residence time in plasma of 125 I-labeled apoA-IV, when injected in association with HDL or LFF, was 1.61 and 0.55 days, respectively. When 125 I-labeled apoA-IV was injected as a free protein, the radioactivity distributed rapidly among the three plasma pools in proportion to their mass. The overall fractional catabolic rate of apoA-IV in plasma was measured in the three normal subjects and averaged 1.56 pools per day. The mean degradation rate of apoA-IV was 8.69 mg/kg X day

Low gray scale values of computerized images of carotid plaques associated with increased levels of triglyceride-rich lipoproteins and with increased plaque lipid content

DEFF Research Database (Denmark)

Grønholdt, Marie-Louise M.; Nordestgaard, Børge; Weibe, Britt M.

1997-01-01

Relatioin between low gray scale values in computerized images of carotid plaques and 1) plasma levels of triglyceride-rich lipoproteins and 2) plaque lipid content......Relatioin between low gray scale values in computerized images of carotid plaques and 1) plasma levels of triglyceride-rich lipoproteins and 2) plaque lipid content...

Role of low density lipoprotein in the activation of plasma lysolecithin acyltransferase activity. Effect of chemical and enzymatic modifications of the lipoprotein on enzyme activity.

Science.gov (United States)

Subbaiah, P V; Chen, C H; Bagdade, J D; Albers, J J

1985-01-01

The effect of various chemical and enzymatic modifications of low density lipoprotein (LDL) on its ability to activate the isolated human plasma lysolecithin acyltransferase (LAT) was studied. Removal of all lipids from LDL resulted in the complete loss of LAT activation. Removal of only neutral lipids by extraction with heptane retained up to 50% of the original activity, which was not increased further by reconstitution of the LDL with the extracted lipids. Hydrolysis of the diacylphosphoglycerides of the LDL with phospholipases resulted in complete loss of LAT activation which was partially restored by the addition of egg lecithin. Hydrolysis of more than 4% of LDL protein by trypsin led to a linear decrease in activity with complete loss of activity occurring when about 25% of the LDL protein is hydrolyzed. Modification of the arginine groups of LDL reversibly inhibited the activation of LAT. Modification of lysine residues of LDL by acetylation, acetoacetylation or succinylation also abolished its ability to activate lysolecithin acylation.

Elevated Lipoprotein(A Impairs Platelet Radiolabeling Yield

Directory of Open Access Journals (Sweden)

Susanne Granegger

2015-02-01

Full Text Available Objectives: Platelet radiolabeling in clinical routine usually results in labeling efficiencies (LE above 80%. A variety of risk factors and clinical conditions are known to impair platelet labeling yield, among them elevated triglycerides and low-density lipoproteins. The potential influence of lipoprotein(a (Lp(a, an atherogenic lipoprotein particle containing a kringle subunit, which is widely found in the proteins of fibrinolysis pathway, has never been studied. Normal Lp(a levels range below 30 mg/ dl. The exact prevalence of elevated Lp(a is unknown, most likely ranging below 10%. Even more rare is an isolated elevation despite an otherwise normal lipoprotein profile. Methods: We examined the role of isolated elevated Lp(a (> 50 mg/dl, ranging up to 440 mg/dl compared to patients with normal lipid profile. Platelets were radiolabeled with in-111-oxine at 37 °C for 5 minutes using ISORBE-consensus methodology. Results: The findings indicate that already at levels below 100 mg/dl Lp(a decreases LE. LE assessment after cross-incubation of hyper-Lp(a platelets with normal Lp(a plasma and vice versa reveals that platelets rather than the plasmatic environment are responsible for the deterioration of labeling yield. This behavior already has been reported for elevated low-density lipoproteins. Apparently, the quantitative influence of LDL and Lp(a/mg is comparable. Plotting the sum of LDL and Lp(a versus LE reveals a clear significant negative correlation. Conclusion: As extremely elevated Lp(a, particularly above 150 mg/dl, may significantly impair labeling results. We therefore recommend to include extremely elevated Lp(a into the list of parameters, which should be known before performing radiolabeling of human platelets.

Absorption and transport of deuterium-substituted 2R,4'R,8'R-alpha-tocopherol in human lipoproteins

International Nuclear Information System (INIS)

Traber, M.G.; Ingold, K.U.; Burton, G.W.; Kayden, H.J.

1988-01-01

Oral administration of a single dose of tri- or hexadeuterium substituted 2R,4'R,8'R-alpha-tocopheryl acetate (d3- or d6-alpha-T-Ac) to humans was used to follow the absorption and transport of vitamin E in plasma lipoproteins. Three hr after oral administration of d3-alpha-T-Ac (15 mg) to 2 subjects, plasma levels of d3-alpha-T were detectable; these increased up to 10 hr, reached a plateau at 24 hr, then decreased. Following administration of d6-alpha-T-Ac (15-16 mg) to 2 subjects, the percentage of deuterated tocopherol relative to the total tocopherol in chylomicrons increased more rapidly than the corresponding percentage in whole plasma. Chylomicrons and plasma lipoproteins were isolated from 2 additional subjects following administration of d3-alpha-T-Ac (140 or 60 mg). The percentage of deuterated tocopherol relative to the total tocopherol increased most rapidly in chylomicrons, then in very low density lipoproteins (VLDL), followed by essentially identical increases in low and high density lipoproteins (LDL and HDL, respectively) and lastly, in the red blood cells. This pattern of appearance of deuterated tocopherol is consistent with the concept that newly absorbed vitamin E is secreted by the intestine into chylomicrons; subsequently, chylomicron remnants are taken up by the liver from which the vitamin E is secreted in VLDL. The metabolism of VLDL in the circulation results in the simultaneous delivery of vitamin E into LDL and HDL

Improvement of Lipid Profile Is Accompanied by Atheroprotective Alterations in High-Density Lipoprotein Composition Upon Tumor Necrosis Factor Blockade A Prospective Cohort Study in Ankylosing Spondylitis

NARCIS (Netherlands)

Eijk, van I.C.; Vries, de M.K.; Levels, J.H.M.; Peters, M.J.L.; Huizer, E.E.; Dijkmans, B.A.C.; Horst - Bruinsma, van der I.E.; Hazenberg, B.P.C.; Stadt, van de R.J.; Wolbink, G.; Nurmohamed, M.T.

2009-01-01

Objective. Cardiovascular mortality is increased in ankylosing spondylitis (AS), and inflammation plays an important role. Inflammation deteriorates the lipid profile and alters high-density lipoprotein cholesterol (HDL-c) composition, reflected by increased concentrations of serum amyloid A (SAA)

Effect of a Diet Enriched with Fresh Coconut Saturated Fats on Plasma Lipids and Erythrocyte Fatty Acid Composition in Normal Adults.

Science.gov (United States)

Nagashree, Rokkam Shankar; Manjunath, N K; Indu, M; Ramesh, M; Venugopal, V; Sreedhar, P; Pavithra, N; Nagendra, Hongasandra R

2017-07-01

The objective of this study was to compare the effects of increased saturated fatty acid (SFA) (provided by fresh coconut) versus monounsaturated fatty acid (MUFA) intake (provided by a combination of groundnuts and groundnut oil) on plasma lipids and erythrocyte fatty acid (EFA) composition in healthy adults. Fifty-eight healthy volunteers, randomized into 2 groups, were provided standardized diet along with 100 g fresh coconut or groundnuts and groundnut oil combination for 90 days in a Yoga University. Fasting blood samples were collected before and after the intervention period for the measurement of plasma lipids and EFA profile. Coconut diet increased low-density lipoprotein (LDL) and high-density lipoprotein (HDL) levels significantly. In contrast, the groundnut diet decreased total cholesterol (TC), mainly due to a decrease in HDL levels. There were no differences in the major SFA of erythrocytes in either group. However, coconut consumption resulted in an increase in C14:0 and C24:0 along with a decrease in levels of C18:1 n9 (oleic acid). There was a significant increase in levels of C20:3 n6 (dihomo-gamma linolenic acid, DGLA). Consumption of SFA-rich coconut for 3 months had no significant deleterious effect on erythrocytes or lipid-related factors compared to groundnut consumption. On the contrary, there was an increase in the anti-atherogenic HDL levels and anti-inflammatory precursor DGLA in erythrocyte lipids. This suggests that coconut consumption may not have any deleterious effects on cardiovascular risk in normal subjects.

One precursor, three apolipoproteins: the relationship between two crustacean lipoproteins, the large discoidal lipoprotein and the high density lipoprotein/β-glucan binding protein.

Science.gov (United States)

Stieb, Stefanie; Roth, Ziv; Dal Magro, Christina; Fischer, Sabine; Butz, Eric; Sagi, Amir; Khalaila, Isam; Lieb, Bernhard; Schenk, Sven; Hoeger, Ulrich

2014-12-01

The novel discoidal lipoprotein (dLp) recently detected in the crayfish, differs from other crustacean lipoproteins in its large size, apoprotein composition and high lipid binding capacity, We identified the dLp sequence by transcriptome analyses of the hepatopancreas and mass spectrometry. Further de novo assembly of the NGS data followed by BLAST searches using the sequence of the high density lipoprotein/1-glucan binding protein (HDL-BGBP) of Astacus leptodactylus as query revealed a putative precursor molecule with an open reading frame of 14.7 kb and a deduced primary structure of 4889 amino acids. The presence of an N-terminal lipid bind- ing domain and a DUF 1943 domain suggests the relationship with the large lipid transfer proteins. Two-putative dibasic furin cleavage sites were identified bordering the sequence of the HDL-BGBP. When subjected to mass spectroscopic analyses, tryptic peptides of the large apoprotein of dLp matched the N-terminal part of the precursor, while the peptides obtained for its small apoprotein matched the C-terminal part. Repeating the analysis in the prawn Macrobrachium rosenbergii revealed a similar protein with identical domain architecture suggesting that our findings do not represent an isolated instance. Our results indicate that the above three apolipoproteins (i.e HDL-BGBP and both the large and the small subunit of dLp) are translated as a large precursor. Cleavage at the furin type sites releases two subunits forming a heterodimeric dLP particle, while the remaining part forms an HDL-BGBP whose relationship with other lipoproteins as well as specific functions are yet to be elucidated.

Tungsten-microdiamond composites for plasma facing components

International Nuclear Information System (INIS)

Livramento, V.; Nunes, D.; Correia, J.B.; Carvalho, P.A.; Mardolcar, U.; Mateus, R.; Hanada, K.; Shohoji, N.; Fernandes, H.; Silva, C.; Alves, E.

2011-01-01

Tungsten is considered as one of promising candidate materials for plasma facing component in nuclear fusion reactors due to its resistance to sputtering and high melting point. High thermal conductivity is also a prerequisite for plasma facing components under the unique service environment of fusion reactor characterised by the massive heat load, especially in the divertor area. The feasibility of mechanical alloying of nanodiamond and tungsten, and the consolidation of the composite powders with Spark Plasma Sintering (SPS) was previously demonstrated. In the present research we report on the use of microdiamond instead of nanodiamond in such composites. Microdiamond is more favourable than nanodiamond in view of phonon transport performance leading to better thermal conductivity. However, there is a trade off between densification and thermal conductivity as the SPS temperature increases tungsten carbide formation from microdiamond is accelerated inevitably while the consolidation density would rise.

Effect of plasma nitriding on electrodeposited Ni–Al composite coating

DEFF Research Database (Denmark)

Daemi, N.; Mahboubi, F.; Alimadadi, Hossein

2011-01-01

In this study plasma nitriding is applied on nickel–aluminum composite coating, deposited on steel substrate. Ni–Al composite layers were fabricated by electro-deposition process in Watt’s bath containing Al particles. Electrodeposited specimens were subjected to plasma atmosphere comprising of N2......–20% H2, at 500°C, for 5h. The surface morphology investigated, using a scanning electron microscope (SEM) and the surface roughness was measured by use of contact method. Chemical composition was analyzed by X-ray fluorescence spectroscopy and formation of AlN phase was confirmed by X-ray diffraction....... The corrosion resistance of composite coatings was measured by potentiodynamic polarization in 3.5% NaCl solution. The obtained results show that plasma nitriding process leads to an increase in microhardness and corrosion resistance, simultaneously....

Blood lipid concentrations and lipoprotein patterns in captive and wild American black bears (Ursus americanus).

Science.gov (United States)

Frank, Nicholas; Elliott, Sarah B; Allin, Shawn B; Ramsay, Edward C

2006-02-01

To compare blood lipid concentrations and lipoprotein patterns for captive and wild American black bears (Ursus americanus). 7 captive and 9 wild adult (> or = 4 years old) black bears. Blood was collected from 2 groups of captive black bears (groups A and B) and 1 group of wild black bears (group C). Blood triglyceride (TG) and cholesterol concentrations were compared among groups. Plasma lipoproteins were isolated by use of a self-generating gradient of iodixanol, and lipoprotein patterns were compared between groups A and B. Captive bears (mean +/- SD, 187.8 +/- 44.4 kg) weighed significantly more than wild bears (mean, 104.8 +/- 41.4 kg), but mean body weight did not differ between groups A and B. Mean blood TG concentrations for groups B (216.8 +/- 16.0 mg/dL) and C (190.7 +/- 34.0 mg/dL) were significantly higher than that of group A (103.9 +/- 25.3 mg/dL). Mean blood cholesterol concentration was also significantly higher for group B (227.8 +/- 8.2 mg/dL) than for groups A (171.7 +/- 35.5 mg/dL) or C (190.8 +/- 26.8 mg/dL). Mean very-low-density lipoprotein TG and low-density lipoprotein cholesterol concentrations were 2- and 3-fold higher, respectively, for group B, compared with concentrations for group A. Blood lipid concentrations vary significantly among populations of black bears. Plasma lipoprotein patterns of captive bears differed significantly between colonies and may have reflected differences in diet or management practices.

Lipoprotein-a

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/007262.htm Lipoprotein-a To use the sharing features on this page, please enable JavaScript. Lipoproteins are molecules made of proteins and fat. They ...

The Human Pathogen Streptococcus pyogenes Releases Lipoproteins as Lipoprotein-rich Membrane Vesicles.

Science.gov (United States)

Biagini, Massimiliano; Garibaldi, Manuela; Aprea, Susanna; Pezzicoli, Alfredo; Doro, Francesco; Becherelli, Marco; Taddei, Anna Rita; Tani, Chiara; Tavarini, Simona; Mora, Marirosa; Teti, Giuseppe; D'Oro, Ugo; Nuti, Sandra; Soriani, Marco; Margarit, Immaculada; Rappuoli, Rino; Grandi, Guido; Norais, Nathalie

2015-08-01

Bacterial lipoproteins are attractive vaccine candidates because they represent a major class of cell surface-exposed proteins in many bacteria and are considered as potential pathogen-associated molecular patterns sensed by Toll-like receptors with built-in adjuvanticity. Although Gram-negative lipoproteins have been extensively characterized, little is known about Gram-positive lipoproteins. We isolated from Streptococcus pyogenes a large amount of lipoproteins organized in vesicles. These vesicles were obtained by weakening the bacterial cell wall with a sublethal concentration of penicillin. Lipid and proteomic analysis of the vesicles revealed that they were enriched in phosphatidylglycerol and almost exclusively composed of lipoproteins. In association with lipoproteins, a few hypothetical proteins, penicillin-binding proteins, and several members of the ExPortal, a membrane microdomain responsible for the maturation of secreted proteins, were identified. The typical lipidic moiety was apparently not necessary for lipoprotein insertion in the vesicle bilayer because they were also recovered from the isogenic diacylglyceryl transferase deletion mutant. The vesicles were not able to activate specific Toll-like receptor 2, indicating that lipoproteins organized in these vesicular structures do not act as pathogen-associated molecular patterns. In light of these findings, we propose to name these new structures Lipoprotein-rich Membrane Vesicles. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Molybdenum disilicide composites produced by plasma spraying

International Nuclear Information System (INIS)

Castro, R.G.; Hollis, K.J.; Kung, H.H.; Bartlett, A.H.

1998-01-01

The intermetallic compound, molybdenum disilicide (MoSi 2 ) is being considered for high temperature structural applications because of its high melting point and superior oxidation resistance at elevated temperatures. The lack of high temperature strength, creep resistance and low temperature ductility has hindered its progress for structural applications. Plasma spraying of coatings and structural components of MoSi 2 -based composites offers an exciting processing alternative to conventional powder processing methods due to superior flexibility and the ability to tailor properties. Laminate, discontinuous and in situ reinforced composites have been produced with secondary reinforcements of Ta, Al 2 O 3 , SiC, Si 3 N 4 and Mo 5 Si 3 . Laminate composites, in particular, have been shown to improve the damage tolerance of MoSi 2 during high temperature melting operations. A review of research which as been performed at Los Alamos National Laboratory on plasma spraying of MoSi 2 -based composites to improve low temperature fracture toughness, thermal shock resistance, high temperature strength and creep resistance will be discussed

Serum lipids and lipoproteins in patients with psoriasis.

Science.gov (United States)

Taheri Sarvtin, Mehdi; Hedayati, Mohammad Taghi; Shokohi, Tahereh; HajHeydari, Zohreh

2014-05-01

Psoriasis is a common chronic and recurrent inflammatory skin disorder characterized by hyperproliferation of keratinocytes and infiltration of T cells, monocytes/macrophages and neutrophils into dermal and epidermal layers of the skin. The prevalence of cardiovascular disorders in these patients is remarkably higher compared to normal individuals, which seems to be associated with the hyperlipidemia. This study was designed and conducted to investigate the serum lipid profile in psoriatic patients and its association with the severity of disease. This case-control study was performed on 50 plaque-type psoriasis patients and 50 healthy individuals as control, matched for age and sex. Blood samples were collected after 14 h fasting. Serum triglyceride, cholesterol and lipoproteins were assayed using the standard kit (made by Pars Azmon Co. Iran). Certain parameters, including serum triglyceride, cholesterol, low density lipoprotein (LDL), and very low density lipoprotein (VLDL), were significantly higher in the case group compared to the controls (P lipoprotein (HDL) was significantly lower in the former (P < 0.001). In addition, there was a significant relationship between severity of psoriasis and serum lipid profile. The results have revealed the higher plasma level of lipids in psoriatic patients. This may elevate the risk of atherosclerosis, particularly cardiovascular disorders. Therefore, from the epidemiological point of view, screening psoriatic patients, particularly those with severe psoriasis, is recommended.

Lipoprotein Apheresis for Lipoprotein(a)-Associated Cardiovascular Disease

DEFF Research Database (Denmark)

Roeseler, Eberhard; Julius, Ulrich; Heigl, Franz

2016-01-01

OBJECTIVE: Lipoprotein(a)-hyperlipoproteinemia (Lp(a)-HLP) along with progressive cardiovascular disease has been approved as indication for regular lipoprotein apheresis (LA) in Germany since 2008. We aimed to study the long-term preventive effect of LA and to assess hypothetical clinical correl...

On methods of measuring the relative plasma composition by active charge exchange

International Nuclear Information System (INIS)

Herrmann, W.

1991-04-01

Two methods of measuring the hydrogenic composition of plasma with an active diagnostic beam are discussed: Evaluation at equal energies of the neutrals leaving the plasma and at equal velocities. Evaluation at equal velocity has the advantage that the plasma composition, particle penetration and stripping efficiency of the analyzer do not enter the evaluation. The only plasma parameter that has to be known is the plasma temperature. If measurement at two different velocities is possible, the temperature can also be evaluated from the corresponding four fluxes without any further knowledge of plasma or beam parameters. It is discussed under what circumstances evaluation of the plasma composition is possible for non-Maxwellian distribution functions. As the halo effect may be the main source of error, it is shown that the application of a helium beam may considerably reduce this problem. (orig.)

Moderate alcohol consumption and changes in postprandial lipoproteins of premenopausal and postmenopausal women: a diet-controlled, randomized intervention study.

Science.gov (United States)

van der Gaag, M S; Sierksma, A; Schaafsma, G; van Tol, A; Geelhoed-Mieras, T; Bakker, M; Hendriks, H F

2000-01-01

Moderate alcohol consumption is associated with a reduced risk of coronary heart disease. Earlier studies in men have shown that moderate alcohol consumption affects lipoprotein metabolism and hemostasis. In this diet-controlled, randomized, crossover trial, we investigated the effect on lipoprotein metabolism of moderate consumption of red wine or red grape juice with evening dinner for 3 weeks in premenopausal women using oral contraceptives and in postmenopausal women. After 3 weeks, blood samples were collected 1 hour before dinner up to 19 hours after starting dinner at 2-hour or 4-hour intervals. Plasma triglyceride concentrations and very low density lipoprotein (VLDL) triglyceride levels peaked 3 hours after dinner with wine in both premenopausal and postmenopausal women. After wine consumption, the overall high-density lipoprotein (HDL) cholesterol level was increased in postmenopausal women (mean increase 0.17 mmol/L, or 12%, p = 0.03), and the plasma low-density lipoprotein (LDL) cholesterol level was reduced in premenopausal women (mean reduction 0.35 mmol/L, or 12%, p = 0.01) as compared with grape juice consumption. The findings suggest that postprandial lipoprotein metabolism after moderate alcohol consumption differs between oral contraceptive-using premenopausal women and postmenopausal women. The response of postmenopausal women to alcohol resembled the response found in earlier studies in men.

Impaired plasma lipid profiles in acute hepatitis

Directory of Open Access Journals (Sweden)

Wang Yongzhong

2010-01-01

Full Text Available Abstract The present study examined plasma lipid profiles in thirty patients suffered from acute viral hepatitis. Patients' blood samples were collected at both the debut and recovery of diseases. Thirty sex and age matched normal subjects were included as controls. Plasma total triglycerides (TG, total cholesterol, high density lipoprotein cholesterol (HDL-C, low density lipoprotein cholesterol (LDL-C, apolipoprotein AI (ApoAI, apolipoprotein B (ApoB, lipoprotein (a (Lp(a, blood coagulation status including prothrombin complex activity and activated partial tromboplastin time (APTT, and hepatic functions were determined by the automatic biochemical analytical instrument. It demonstrated that plasma levels of total cholesterol, HDL-C and apoAI were significantly lower in the patients at the acute phase of hepatitis than those in normal subjects, whereas plasma levels of TG and LDL-C were obviously higher in the patients than in normal subjects (P

Relation of plasma lipoprotein(a) with myocardial viability and left ventricular performance in survivors of myocardial infarction

International Nuclear Information System (INIS)

Aksoy, M.; Goktekin, O.; Gursurer, M.; Emre, A.; Bilge, M.; Yesilcimen, K.; Ersek, B.; Kepekci, Y.; Akdemir, I.

1999-01-01

Previous studies have reported that high serum lipoprotein(a) levels may be responsible for total occlusion of the infarct-related artery via inhibition of intrinsic fibrinolysis during acute myocardial infarction. We evaluated whether this would result in a greater extent of myocardial necrosis and impaired left ventricular function in patients with high lipoprotein(a) levels. Sixty-eight patients with prior myocardial infarction, who were not receiving thrombolytic therapy underwent coronary angiography and stress-redistribution-reinjection Tl-201 scintigraphy. Antegrade TIMI flow in the infarct-related artery was lower (1.54±1.14 vs 2.15±1.05; p=0.03) and the collateral index was higher (1.3±1.0 vs 0.8±0.9; p=0.07) in patients with high lipoprotein(a) levels (>30 mg/dl) compared to those with low lipoprotein(a) levels (≤30 mg/dl). Regional wall motion score index was lower (0.8±0.8 vs 1.4±0.5; p=0.008) and global ejection fraction was higher (46±10% vs 40±11%; p=0.03) in patients with low lipoprotein(a) levels. On SPECT images, the number of nonviable defects was higher in patients with high lipoprotein(a) levels (4.0±2.5 vs 1.9±1.3; p=0.0002), whereas the number of viable defects was higher in those with low lipoprotein(a) levels (2.5±1.8 vs 1.5±1.3; p=0.02). We conclude, that high lipoprotein(a) levels may prolong the occlusion of infarct-related artery during acute myocardial infarction and lead to a greater extent of myocardial necrosis and impaired left ventricular function. (author)

Preferential Interactions between ApoE-containing Lipoproteins and Aβ Revealed by a Detection Method that Combines Size Exclusion Chromatography with Non-Reducing Gel-shift

Science.gov (United States)

LaDu, Mary Jo; Munson, Gregory W.; Jungbauer, Lisa; Getz, Godfrey S.; Reardon, Catherine A.; Tai, Leon M.; Yu, Chunjiang

2012-01-01

The association between apolipoprotein E (apoE) and amyloid-β peptide (Aβ) may significantly impact the function of both proteins, thus affecting the etiology of Alzheimer’s disease (AD). However, apoE/Aβ interactions remain fundamentally defined by the stringency of the detection method. Here we use size exclusion chromatography (SEC) as a non-stringent approach to the detection of apoE/Aβ interactions in solution, specifically apoE and both endogenous and exogenous Aβ from plasma, CSF and astrocyte conditioned media. By SEC analysis, Aβ association with plasma and CNS lipoproteins is apoE-dependent. While endogenous Aβ elutes to specific human plasma lipoproteins distinct from those containing apoE, it is the apoE-containing lipoproteins that absorb excess amounts of exogenous Aβ40. In human CSF, apoE, endogenous Aβ and phospholipid elute in an almost identical profile, as do apoE, exogenous Aβ and phospholipid from astrocyte conditioned media. Combining SEC fractionation with subsequent analysis for SDS-stable apoE/Aβ complex reveals that apoE-containing astrocyte lipoproteins exhibit the most robust interactions with Aβ. Thus, standardization of the methods for detecting apoE/Aβ complex is necessary to determine its functional significance in the neuropathology characteristic of AD. Importantly, a systematic understanding of the role of apoE-containing plasma and CNS lipoproteins in Aβ homeostasis could potentially contribute to identifying a plasma biomarker currently over-looked because it has multiple components. PMID:22138302

Compared with Powdered Lutein, a Lutein Nanoemulsion Increases Plasma and Liver Lutein, Protects against Hepatic Steatosis, and Affects Lipoprotein Metabolism in Guinea Pigs.

Science.gov (United States)

Murillo, Ana Gabriela; Aguilar, David; Norris, Gregory H; DiMarco, Diana M; Missimer, Amanda; Hu, Siqi; Smyth, Joan A; Gannon, Sarah; Blesso, Christopher N; Luo, Yangchao; Fernandez, Maria Luz

2016-10-01

It is not clear how oil-in-water nanoemulsions of lutein may affect bioavailability and consequently alter lipoprotein metabolism, oxidative stress, and inflammation. The bioavailability as well as effects of a powdered lutein (PL) and an oil-in-water lutein nanoemulsion (NANO; particle size: 254.2 nm; polydispersity index: 0.29; and ζ-potential: -65 mV) on metabolic variables in liver, plasma, and adipose tissue in a guinea pig model of hepatic steatosis were evaluated. Twenty-four 2-mo-old male Hartley guinea pigs, weighing 200-300 g (n = 8/group), were fed diets containing 0.25 g cholesterol/100 g to induce liver injury for the duration of the study. They were allocated to control (0 mg lutein), PL (3.5 mg/d), or NANO (3.5 mg/d) groups. After 6 wk, plasma, liver, and adipose tissue were collected for determination of lutein, plasma lipids, tissue cholesterol, and inflammatory cytokines. The NANO group had 2-fold higher concentrations of lutein in plasma (P guinea pigs. © 2016 American Society for Nutrition.

Plasma etching a ceramic composite. [evaluating microstructure

Science.gov (United States)

Hull, David R.; Leonhardt, Todd A.; Sanders, William A.

1992-01-01

Plasma etching is found to be a superior metallographic technique for evaluating the microstructure of a ceramic matrix composite. The ceramic composite studied is composed of silicon carbide whiskers (SiC(sub W)) in a matrix of silicon nitride (Si3N4), glass, and pores. All four constituents are important in evaluating the microstructure of the composite. Conventionally prepared samples, both as-polished or polished and etched with molten salt, do not allow all four constituents to be observed in one specimen. As-polished specimens allow examination of the glass phase and porosity, while molten salt etching reveals the Si3N4 grain size by removing the glass phase. However, the latter obscures the porosity. Neither technique allows the SiC(sub W) to be distinguished from the Si3N4. Plasma etching with CF4 + 4 percent O2 selectively attacks the Si3N4 grains, leaving SiC(sub W) and glass in relief, while not disturbing the pores. An artifact of the plasma etching reaction is the deposition of a thin layer of carbon on Si3N4, allowing Si3N4 grains to be distinguished from SiC(sub W) by back scattered electron imaging.

Measurements of plasma composition in the TEXTOR tokamak by collective Thomson scattering

DEFF Research Database (Denmark)

Stejner Pedersen, Morten; Korsholm, Søren Bang; Nielsen, Stefan Kragh

2012-01-01

We demonstrate the use of collective Thomson scattering (CTS) for spatially localized measurements of the isotopic composition of magnetically confined fusion plasmas. The experiments were conducted in the TEXTOR tokamak by scattering millimeter-wave probe radiation off plasma fluctuations...... with wave vector components nearly perpendicular to the magnetic field. Under such conditions the sensitivity of the CTS spectrum to plasma composition is enhanced by the spectral signatures of the ion cyclotron motion and of weakly damped ion Bernstein waves. Recent experiments on TEXTOR demonstrated...... the ability to resolve these signatures in the CTS spectrum as well as their sensitivity to the ion species mix in the plasma. This paper shows that the plasma composition can be inferred from the measurements through forward modeling of the CTS spectrum. We demonstrate that spectra measured in plasmas...

Temporal development of the plasma composition of Zr and Cr metal plasma streams in a N2 environment

International Nuclear Information System (INIS)

Rosen, Johanna; Anders, Andre; Hultman, Lars; Schneider, Jochen M.

2003-01-01

We describe the temporal development of the plasma composition in a pulsed plasma stream generated by cathodic arc. Cathodes of Zr and Cr were operated at various nitrogen pressures. The time resolved plasma composition for the cathode materials was analyzed with time-of-flight charge-to-mass spectrometry, and was found to be a strong function of the nitrogen pressure. Large plasma composition gradients were detected within the first 60 (micro)s of the pulse, the nitrogen ion concentration increasing with increasing pressure. The results are explained by the formation and erosion of a compound layer formed at the cathode surface in the presence of a reactive gas. The average charge state was also found to be affected by the reactive gas pressure as well as by the time after ignition. The charge states were highest in the beginning of the pulse at low nitrogen pressure, decreasing to a steady-state value at higher pressure. These results are of importance for reactive plasma processing and for controlling of the evolution of thin film composition and microstructure

IMPACT OF DIET, EXERCISE AND DIET COMBINED WITH EXERCISE PROGRAMS ON PLASMA LIPOPROTEIN AND ADIPONECTIN LEVELS IN OBESE GIRLS

Directory of Open Access Journals (Sweden)

Omar Ben Ounis

2008-12-01

Full Text Available We studied the effect of three programs, diet restriction (D, individualized exercise training (E at the maximal lipid oxidation point (LIPOXmax and diet combined with exercise (D+E, on body mass, plasma lipoprotein and adiponectin levels in obese girls. Eighteen obese adolescents girls aged 12-14 years were studied. A longitudinal intervention was carried out, consisting of a two-month diet (D; -500 kcal·day-1, of individualized exercise (E; 4 days/week, 90 min·day-1 and of diet combined with exercise (D+E. Body mass, body mass index (BMI, body fat mass, waist circumference, substrate crossover point, LIPOXmax point, homeostasis model assessment (HOMA-IR index, fasting levels of lipids and circulatory adiponectin, were measured in all subjects before and after the program. In subjects of the D+E group, body mass, BMI, body fat mass, waist circumference, HOMA-IR, low-density lipoprotein cholesterol (LDL-C and total cholesterol / high-density lipoprotein cholesterol (TC/HDL-C ratio were significantly lower, and HDL-C and adiponectin were higher after the program than that of subjects in the D or E groups. Diet/exercise improved the ability to oxidize lipids during exercise (crossover point: + 18.5 ± 3.4 of % Wmax; p < 0.01 and fat oxidation rate at LIPOXmax: + 89.7 ± 19.7 mg·min-1; p < 0.01. In the D+E group, significant correlations were found between changes in body mass and adiponectin and between changes in the TC/HDL-C ratio and LIPOXmax. These findings show that the combined program of diet restriction and individualized exercise training at the LIPOXmax point is necessary to simultaneously improve body mass loss, adiponectin levels, as well as metabolic parameters, in obese girls

Plasma Lipoprotein-associated Phospholipase A(2) Is Inversely Correlated with Proprotein Convertase Subtilisin-kexin Type 9

NARCIS (Netherlands)

Constantinides, Alexander; Kappelle, Paul J.W.H.; Lambert, Gilles; Dullaart, Robin P. F.

Background and Aims. Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is a proatherogenic phospholipase A(2), which is predominantly complexed to low-density lipoprotein (LDL) particles. Proprotein convertase subtilisin-kexin type 9 (PCSK9) provides a key step in LDL metabolism by stimulating

Oxygen plasma treatments of jute fibers in improving the mechanical properties of jute/HDPE composites

Energy Technology Data Exchange (ETDEWEB)

Sever, K. [Department of Mechanical Engineering, Dokuz Eylul University, 35100, Izmir (Turkey); Erden, S. [Department of Mechanical Engineering, Ege University, 35100, Izmir (Turkey); Guelec, H.A. [Department of Food Engineering, Yuzuncu Yil University, 65250, Van (Turkey); Seki, Y., E-mail: yoldas.seki@deu.edu.tr [Department of Chemistry, Dokuz Eylul University, 35160, Buca, Izmir (Turkey); Sarikanat, M. [Department of Mechanical Engineering, Ege University, 35100, Izmir (Turkey)

2011-09-15

Highlights: {yields} To improve mechanical properties of jute/HDPE composites, jute fabric was subjected to oxygen plasma treatment. {yields} LF and RF plasma systems at different plasma powers were used for treatment. {yields} In LF system, interlaminar shear strength, tensile and flexure strengths showed a tendency to increase at plasma powers of 30 and 60 W. - Abstract: The surfaces of jute fabrics have been oxygen plasma treated using low frequency (LF) and radio frequency (RF) plasma systems at different plasma powers (30, 60, and 90 W) for 15 min to improve the mechanical properties of jute fiber/HDPE (high density polyethylene) composites. The effect of oxygen plasma treatment on the functional groups of jute fibers was examined by X-ray photoelectron spectroscopy (XPS) analysis. Effects of oxygen plasma treatments on the mechanical properties of jute fiber/HDPE composites were investigated by means of tensile, flexure, and short-beam shear tests. Surface morphology of the fractured surfaces of composites was observed by using scanning electron microscopy (SEM). When RF plasma system was used, the interlaminar shear strength (ILSS) values of the composites increased with increasing plasma power. Similarly, in LF plasma system, ILSS values showed a tendency to increase at plasma powers of 30 and 60 W. However, increasing of plasma power to 90 W decreased the ILSS value of jute/HDPE composite. Also, tensile and flexure strengths of the composites showed similar trends.

Oxygen plasma treatments of jute fibers in improving the mechanical properties of jute/HDPE composites

International Nuclear Information System (INIS)

Sever, K.; Erden, S.; Guelec, H.A.; Seki, Y.; Sarikanat, M.

2011-01-01

Highlights: → To improve mechanical properties of jute/HDPE composites, jute fabric was subjected to oxygen plasma treatment. → LF and RF plasma systems at different plasma powers were used for treatment. → In LF system, interlaminar shear strength, tensile and flexure strengths showed a tendency to increase at plasma powers of 30 and 60 W. - Abstract: The surfaces of jute fabrics have been oxygen plasma treated using low frequency (LF) and radio frequency (RF) plasma systems at different plasma powers (30, 60, and 90 W) for 15 min to improve the mechanical properties of jute fiber/HDPE (high density polyethylene) composites. The effect of oxygen plasma treatment on the functional groups of jute fibers was examined by X-ray photoelectron spectroscopy (XPS) analysis. Effects of oxygen plasma treatments on the mechanical properties of jute fiber/HDPE composites were investigated by means of tensile, flexure, and short-beam shear tests. Surface morphology of the fractured surfaces of composites was observed by using scanning electron microscopy (SEM). When RF plasma system was used, the interlaminar shear strength (ILSS) values of the composites increased with increasing plasma power. Similarly, in LF plasma system, ILSS values showed a tendency to increase at plasma powers of 30 and 60 W. However, increasing of plasma power to 90 W decreased the ILSS value of jute/HDPE composite. Also, tensile and flexure strengths of the composites showed similar trends.

Effects of atmospheric air plasma treatment on interfacial properties of PBO fiber reinforced composites

Energy Technology Data Exchange (ETDEWEB)

Zhang, Chengshuang, E-mail: cszhang83@163.com; Li, Cuiyun; Wang, Baiya; Wang, Bin; Cui, Hong

2013-07-01

Poly(p-phenylene benzobisoxazole) (PBO) fiber was modified by atmospheric air plasma treatment. The effects of plasma treatment power and speed on both surface properties of PBO fibers and interfacial properties of PBO/epoxy composites were investigated. Surface chemical composition of PBO fibers were analyzed by X-ray photoelectron spectroscopy (XPS). Surface morphologies of the fibers and interface structures of the composites were examined using scanning electron microscopy (SEM). Interfacial adhesion property of the composites was evaluated by interlaminar shear strength (ILSS). Mechanical properties of PBO multifilament were measured by universal testing machine. The results indicate that atmospheric air plasma treatment introduced some polar or oxygen-containing groups to PBO fiber surfaces, enhanced surface roughness and changed surface morphologies of PBO fibers by plasma etching and oxidative reactions. The plasma treatment also improved interfacial adhesion of PBO/epoxy composites but has little effect on tensile properties of PBO multifilament. The ILSS of PBO/epoxy composites increased to 40.0 MPa after atmospheric air plasma treatment with plasma treatment power of 300 W and treatment speed of 6 m/min.

Optical characterization of composite layers prepared by plasma polymerization

International Nuclear Information System (INIS)

Radeva, E; Hikov, T; Mitev, D; Pramatarova, L; Stroescu, H; Nicolescu, M; Gartner, M; Presker, R

2016-01-01

Thin composite layers from polymer/nanoparticles (Ag-nanoparticles and detonation nanodiamonds) were prepared by plasma polymerization process on the base of hexamethyldisiloxane. The variation of the layer composition was achieved by changing the type of nanoparticles. The optical measurement techniques used were UV-VIS-NIR ellipsometry (SE), Fourier-transformed infrared spectroscopy (FTIR) and Raman spectroscopy. The values of the refractive index determined are in the range 1.30 to 1.42. All samples are transparent with transmission between 85-95% and very smooth. The change in Raman and FTIR spectra of the composites verify the expected bonding between polymer and diamond nanoparticles due to the penetration of the fillers in the polymer matrix. The comparison of the spectra of the corresponding NH3 plasma treated composites revealed that the composite surface becomes more hydrophilic. The obtained results indicate that preparation of layers with desired compositions is possible at a precise control of the detonation nanodiamond materials. (paper)

Contribution of lipoproteins and lipoprotein processing to endocarditis virulence in Streptococcus sanguinis.

Science.gov (United States)

Das, Sankar; Kanamoto, Taisei; Ge, Xiuchun; Xu, Ping; Unoki, Takeshi; Munro, Cindy L; Kitten, Todd

2009-07-01

Streptococcus sanguinis is an important cause of infective endocarditis. Previous studies have identified lipoproteins as virulence determinants in other streptococcal species. Using a bioinformatic approach, we identified 52 putative lipoprotein genes in S. sanguinis strain SK36 as well as genes encoding the lipoprotein-processing enzymes prolipoprotein diacylglyceryl transferase (lgt) and signal peptidase II (lspA). We employed a directed signature-tagged mutagenesis approach to systematically disrupt these genes and screen each mutant for the loss of virulence in an animal model of endocarditis. All mutants were viable. In competitive index assays, mutation of a putative phosphate transporter reduced in vivo competitiveness by 14-fold but also reduced in vitro viability by more than 20-fold. Mutations in lgt, lspA, or an uncharacterized lipoprotein gene reduced competitiveness by two- to threefold in the animal model and in broth culture. Mutation of ssaB, encoding a putative metal transporter, produced a similar effect in culture but reduced in vivo competiveness by >1,000-fold. [(3)H]palmitate labeling and Western blot analysis confirmed that the lgt mutant failed to acylate lipoproteins, that the lspA mutant had a general defect in lipoprotein cleavage, and that SsaB was processed differently in both mutants. These results indicate that the loss of a single lipoprotein, SsaB, dramatically reduces endocarditis virulence, whereas the loss of most other lipoproteins or of normal lipoprotein processing has no more than a minor effect on virulence.

Cholesterol transfer from normal and atherogenic low density lipoproteins to Mycoplasma membranes

International Nuclear Information System (INIS)

Mitschelen, J.J.; St Clair, R.W.; Hester, S.H.

1981-01-01

The purpose of this study was to determine whether the free cholesterol of hypercholesterolemic low density lipoprotein from cholesterol-fed nonhuman primates has a greater potential for surface transfer to cell membranes than does the free cholesterol of normal low density lipoprotein. The low density lipoproteins were isolated from normal and hypercholesterolemic rhesus and cynomolgus monkeys, incubated with membranes from Acholeplasma laidlawii, a mycoplasma species devoid of cholesterol in its membranes, and the mass transfer of free cholesterol determined by measuring membrane cholesterol content. Since these membranes neither synthesize nor esterify cholesterol, nor degrade the protein or cholesterol ester moieties of low density lipoprotein, they are an ideal model with which to study differences in the cholesterol transfer potential of low density lipoprotein independent of the uptake of the intact low density lipoprotein particle. These studies indicate that, even though there are marked differences in the cholesterol composition of normal and hypercholesterolemic low density lipoproteins, this does not result in a greater chemical potential for surface transfer of free cholesterol. Consequently, if a difference in the surface transfer of free cholesterol is responsible for the enhanced ability of hypercholesterolemic low density lipoprotein to promote cellular cholesterol accumulation and, perhaps, also atherosclerosis, it must be the result of differences in the interaction to the hypercholesterolemic low density lipoprotein with the more complicated mammalian cell membranes, rather than differences in the chemical potential for cholesterol transfer

Effect of modified dairy fat on postprandial and fasting plasma lipids and lipoproteins in healthy young men

DEFF Research Database (Denmark)

Tholstrup, T.; Sandström, B.; Hermansen, J.E.

1998-01-01

Fatty acid profile of milk fat can be modified by cow feeding strategies. Our aim was postprandially and after 4 wk to compare the effect of a modified milk fat(M diet) [with 16% of the cholesterolemic saturated fatty acid (C12-16) replaced by mainly oleic and stearic acids] with the effect of D...... diet than M diet (interaction effect, diet x timesP stearic acids may havebeen obscured by the high content of cholesterol-raising saturated fatty acids in milk fat...... diet, including aconventional Danish milk fat on plasma lipids and lipoproteins. A side effect of the cow feeding regime was a 5% (w/w) increase in trans fatty acid in M diet.Eighteen subjects were fed for two periods of 4 wk strictly controlled isoenergetic test diets with 40% of energy from total fat...

Concentration, composition and apolipoprotein B species of very low density lipoprotein subfractions from normolipidemic and hypertriglyceridemic humans.

Science.gov (United States)

Bittolo Bon, G; Cazzolato, G; Zago, S; Avogaro, P

1985-01-01

Lipoproteins in the d less than 1.006 g/ml density range obtained form 13 healthy normolipidemic subjects and from 15 patients affected by primary endogenous hypertriglyceridemia after 14-h fasting were subfractionated by filtration in Biogel A-15 M columns. The mass values and chemical composition of very low density lipoprotein (VLDL) subfractions 1 and 2 thus obtained were studied. In each subfraction the behavior of apolipoprotein B (Apo B) was tested by sodium dodecyl-sulfate polyacrylamide gel electrophoresis. VLDL2 was higher and richer in cholesterol and proteins than VLDL1, while the percentage content of triglycerides was lower. In hypertriglyceridemic patients both VLDL1 and VLDL2 were higher than in normolipidemic subjects, the difference being particularly evident for VLDL1. In both VLDL1 and VLDL2 of nearly all the subjects studied the presence in electrophoretic gels of a large Apo B-100 band and of a minor Apo B-48 band with the appropriate mobility of lymph chylomicrons was detected. The Apo B-100/Apo B-48 ratio was about 6 in VLDL1 and 24 in VLDL2. A trend of a reduced Apo B-100/Apo B-48 ratio was observed in VLDL1 of hypertriglyceridemic patients.

Fe3O4@ZnO core-shell nanocomposites for efficient and repetitive removal of low density lipoprotein in plasma and on blood vessel

International Nuclear Information System (INIS)

Huang, Xiao; Lu, Juan; Yue, Danyang; Fan, Yijuan; Yi, Caixia; Wang, Xiaoying; Zhang, Mengxue; Pan, Jun

2015-01-01

Low density lipoprotein (LDL)-apheresis therapy, which directly removes LDL from plasma by LDL-adsorbents in vitro is found to be clinically effective and safe to lower the LDL content in blood to prevent cardiovascular disease. Thus, developing excellent LDL adsorbents are becoming more and more attractive. Herein, functional Fe 3 O 4 @ZnO core–shell nanocomposites have been synthesized by a facile and eco-friendly two-step method. Not only do they possess high LDL adsorption (in PBS/plasma as well as on blood vessels) and favorable magnetic targeting ability but they can also be reused conveniently, which offer the Fe 3 O 4 @ZnO core–shell nanocomposites significant potential in the removal of LDL in vitro and in vivo. (paper)

Macroporous poly(vinyl alcohol) microspheres bearing phosphate groups as a new adsorbent for low-density lipoprotein apheresis

Energy Technology Data Exchange (ETDEWEB)

Wang Weichao; Xie Hui; Ou Lailiang; Wang Lianyong; Yu Yaoting; Kong Deling [Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Science, Nankai University, Tianjin 300071 (China); Sun Lisha, E-mail: wly@nankai.edu.c, E-mail: kongdeling@nankai.edu.c [General Hospital, Tianjin Medical University, Tianjin 300052 (China)

2009-12-15

A new low-density lipoprotein (LDL) adsorbent with phosphate groups as the ligand was prepared in this study. Macroporous poly(vinyl acetate-co-triallyl isocyanurate) microspheres were prepared using a free-radical suspension polymerization method. A hydrolysis reaction in sodium hydroxide/methanol changed the materials into poly(vinyl alcohol) (PVA) microspheres. Further reaction with phosphorus oxychloride in anhydrous DMF led to the LDL adsorbent PVA-phosphate microspheres. The preparation conditions such as reaction time, temperature and the amount of phosphorus oxychloride were optimized. The adsorption of plasma lipoproteins was examined by in vitro adsorption assays. The influence of adsorption time, plasma volume and ionic strength on the adsorption capacity was investigated. The circulation adsorption showed that the pathogenic lipoproteins in the plasma such as total cholesterol (TC), LDL and triglyceride (TG) could be removed markedly, in which the removal percentages were 42.9%, 45.0% and 44.74%, respectively. However, the reduction of high-density lipoprotein (HDL) and other normal plasma components was very slight. For in vivo experiment, rabbits were fed with high-cholesterol food to develop a hyperlipidemia model and treated by extracorporeal blood perfusion using the PVA-phosphate columns. Eight hyperlipidemia rabbits were treated with the PVA-phosphate adsorbent, and the removal of TC, LDL and TG was 45.03 +- 6.64%, 48.97 +- 9.92% and 35.42 +- 14.17%, respectively. The sterilization and storage tests showed that the adsorbent was chemically and functionally stable. It could be easily sterilized by a common method and stored for months without loss of adsorption capacity. Therefore, this new PVA-phosphate-based LDL adsorbent may have potential for application in LDL apheresis.

Association between ABCG1 polymorphism rs1893590 and high-density lipoprotein (HDL) in an asymptomatic Brazilian population.

Science.gov (United States)

Zago, V H S; Scherrer, D Z; Parra, E S; Panzoldo, N B; Alexandre, F; Nakandakare, E R; Quintão, E C R; de Faria, E C

2015-03-01

ATP binding cassette transporter G1 (ABCG1) promotes lipidation of nascent high-density lipoprotein (HDL) particles, acting as an intracellular transporter. SNP rs1893590 (c.-204A > C) of ABCG1 gene has been previously studied and reported as functional over plasma HDL-C and lipoprotein lipase activity. This study aimed to investigate the relationships of SNP rs1893590 with plasma lipids and lipoproteins in a large Brazilian population. Were selected 654 asymptomatic and normolipidemic volunteers from both genders. Clinical and anthropometrical data were taken and blood samples were drawn after 12 h fasting. Plasma lipids and lipoproteins, as well as HDL particle size and volume were determined. Genomic DNA was isolated for SNP rs1893590 detection by TaqMan(®) OpenArray(®) Real-Time PCR Plataform (Applied Biosystems). Mann-Whitney U, Chi square and two-way ANOVA were the used statistical tests. No significant differences were found in the comparison analyses between the allele groups for all studied parameters. Conversely, significant interactions were observed between SNP and age over plasma HDL-C, were volunteers under 60 years with AA genotype had increased HDL-C (p = 0.048). Similar results were observed in the group with body mass index (BMI) m(2), where volunteers with AA genotype had higher HDL-C levels (p = 0.0034), plus an increased HDL particle size (p = 0.01). These findings indicate that SNP rs1893590 of ABCG1 has a significant impact over HDL-C under asymptomatic clinical conditions in an age and BMI dependent way.

Macroporous poly(vinyl alcohol) microspheres bearing phosphate groups as a new adsorbent for low-density lipoprotein apheresis

International Nuclear Information System (INIS)

Wang Weichao; Xie Hui; Ou Lailiang; Wang Lianyong; Yu Yaoting; Kong Deling; Sun Lisha

2009-01-01

A new low-density lipoprotein (LDL) adsorbent with phosphate groups as the ligand was prepared in this study. Macroporous poly(vinyl acetate-co-triallyl isocyanurate) microspheres were prepared using a free-radical suspension polymerization method. A hydrolysis reaction in sodium hydroxide/methanol changed the materials into poly(vinyl alcohol) (PVA) microspheres. Further reaction with phosphorus oxychloride in anhydrous DMF led to the LDL adsorbent PVA-phosphate microspheres. The preparation conditions such as reaction time, temperature and the amount of phosphorus oxychloride were optimized. The adsorption of plasma lipoproteins was examined by in vitro adsorption assays. The influence of adsorption time, plasma volume and ionic strength on the adsorption capacity was investigated. The circulation adsorption showed that the pathogenic lipoproteins in the plasma such as total cholesterol (TC), LDL and triglyceride (TG) could be removed markedly, in which the removal percentages were 42.9%, 45.0% and 44.74%, respectively. However, the reduction of high-density lipoprotein (HDL) and other normal plasma components was very slight. For in vivo experiment, rabbits were fed with high-cholesterol food to develop a hyperlipidemia model and treated by extracorporeal blood perfusion using the PVA-phosphate columns. Eight hyperlipidemia rabbits were treated with the PVA-phosphate adsorbent, and the removal of TC, LDL and TG was 45.03 ± 6.64%, 48.97 ± 9.92% and 35.42 ± 14.17%, respectively. The sterilization and storage tests showed that the adsorbent was chemically and functionally stable. It could be easily sterilized by a common method and stored for months without loss of adsorption capacity. Therefore, this new PVA-phosphate-based LDL adsorbent may have potential for application in LDL apheresis.

Effect of garlic on plasma lipoprotein(a) concentrations: A systematic review and meta-analysis of randomized controlled clinical trials.

Science.gov (United States)

Sahebkar, Amirhossein; Serban, Corina; Ursoniu, Sorin; Banach, Maciej

2016-01-01

Garlic can play an essential role in the prevention of atherosclerosis, but the research addressing the effect of garlic on the concentration of lipoprotein(a) [Lp(a)] has not been fully demonstrated. The aim of this study was to assess the effect of garlic on plasma Lp(a) concentrations through systematic review of literature and meta-analysis of available randomized controlled trials. The literature search included SCOPUS, PubMed-Medline, ISI Web of Science, and Google Scholar databases up to March 10, 2015 to identify randomized controlled trials investigating the effect of garlic on plasma Lp(a) concentrations. Two independent reviewers extracted data on study characteristics, methods, and outcomes. Overall, the effect of garlic on plasma Lp(a) levels was reported in six trials. Meta-analysis did not suggest a significant alteration in plasma Lp(a) levels after garlic consumption (weighted mean difference [WMD] = 16.86%; 95% confidence interval, -4.59 to 38.31; P = 0.124). This result was robust in the leave-one-out sensitivity analysis. When the studies were categorized according to the duration of supplementation, there was no effect in the subgroup of trials lasting ≤12 wk (WMD = 2.01%; 95% CI, -14.67 to 18.68; P = 0.813) but a significant elevation of plasma Lp(a) concentrations was found in trials lasting >12 wk (WMD = 54.59%; 95% CI, 30.47-78.71; P meta-regression suggested an inverse association between the changes in plasma concentrations of Lp(a) and duration of supplementation (slope 1.71; 95% CI, 0.46-2.97; P = 0.007). The present meta-analysis did not suggest a significant effect of garlic supplementation on the reduction of Lp(a) levels. Copyright © 2016 Elsevier Inc. All rights reserved.

Induction of oxygen free radical generation in human monocytes by lipoprotein(a)

DEFF Research Database (Denmark)

Riis Hansen, P; Kharazmi, A; Jauhiainen, M

1994-01-01

The mechanism behind the association of elevated plasma lipoprotein(a) [Lp(a)] levels with atherosclerotic disease is unknown. In the present study, Lp(a) induced generation of oxygen free radicals by monocytes from selected healthy individuals in vitro. This observation may provide a link between...

Characteristics of polyimide-based composite membranes fabricated by low-temperature plasma polymerization

International Nuclear Information System (INIS)

Dung Thi Tran; Mori, Shinsuke; Suzuki, Masaaki

2008-01-01

Composite membranes were prepared by the deposition of plasma-polymerized allylamine films onto a porous polyimide substrate. The relationship between the plasma conditions and the membrane characteristics was described in terms of monomer flow rate, plasma discharge power, plasma polymerization time, and so on. Scanning electron microscope (SEM) images indicate that the thickness of the plasma polymer layer increased and the membrane skin pore size decreased gradually with the increasing of plasma polymerization time. Fourier transform infrared (FTIR) spectra demonstrate the appearance of amine groups in the plasma deposited polymer and the contact angle measurements indicate that the hydrophilicity of the membrane surfaces increased significantly after plasma polymerization. The composite membranes can reject salt from sodium chloride feed solution, and membrane separation performance depends strongly on the plasma conditions applied during the preparation of the plasma deposited polymer films

Interaction of Olive Oil Phenol Antioxidant Components with Low-density Lipoprotein

Directory of Open Access Journals (Sweden)

ROSA M LAMUELA-RAVENTÓS

2004-01-01

Full Text Available Phenolic compounds have shown to inhibit LDL oxidation in vitro and ex vivo; however, they are hydrosoluble compounds while LDL is a lipoprotein. Analysis of phenolic compounds in LDLs by HPLC is necessary to demonstrate their binding capacity to lipoproteins. We developed and validated a solid phase extraction method (SPE that allowed us the purification of LDL samples and their analysis by HPLC. This methodology allowed us to demonstrate the in vitro binding capacity of tyrosol, one of the main phenolic compounds in olive oil, to LDL. In the intervention dietary study with volunteers, food rich in phenolic compounds affected LDL composition. Changes in LDL phenolics composition are not observed after the short-term ingestion of food rich in phenolic compounds. However, after one week of olive oil consumption and Mediterranean diet there was an increase in phenolics (p=0.021. An accumulative effect seems necessary to observe significative differences in LDL phenolic composition.

Association of plasma fatty acid composition with plasma irisin levels in normal weight and overweight/obese children.

Science.gov (United States)

Viitasalo, A; Ågren, J; Venäläinen, T; Pihlajamäki, J; Jääskeläinen, J; Korkmaz, A; Atalay, M; Lakka, T A

2016-08-01

Irisin has been suggested to protect against overweight. There are no previous data on the association of plasma fatty acid (FA) composition with plasma irisin. We studied the association of FA composition with plasma irisin in normal weight and overweight/obese children. This cross-sectional study included pre-pubertal children (388 normal weight children and 55 overweight/obese children); 6-9 years of age, taking part in the Physical Activity and Nutrition in Children Study. After an overnight fast, we measured plasma FA composition by gas chromatography and plasma irisin levels by enzyme-linked immunosorbent assay. Higher proportion of total monounsaturated fatty acids in plasma cholesteryl esters (CEs) (β = 0.139, P = 0.003) and phospholipids (PLs) (β = 0.147, P = 0.002) and lower proportion of total polyunsaturated fatty acids in plasma CE (β = -0.130, P = 0.006) and PL (β = -0.165, P overweight/obese children compared to normal weight children. Higher proportion of γ-linolenic acid (β = 0.324, P = 0.017) and lower proportion of linoleic acid (β = -0.397, P = 0.005) in plasma CE were related to higher plasma irisin level among overweight/obese children, indicating the direct association of estimated D6D activity in plasma CE (β = 0.343, P = 0.011) with plasma irisin. Furthermore, higher proportion of oleic acid in plasma CE (β = 0.345, P = 0.012) and PL (β = 0.292, P = 0.033) and higher proportion of adrenic acid (β = 0.366, P = 0.008) and docosapentaenoic acid (β = 0.351, P = 0.010) in plasma PL were associated with higher plasma irisin level among overweight/obese children. Metabolically unfavourable plasma FA profile was associated with higher plasma irisin level especially in overweight/obese children, suggesting that excess body fat might modulate these relationships. © 2015 World Obesity.

Rethinking reverse cholesterol transport and dysfunctional high-density lipoproteins.

Science.gov (United States)

Gillard, Baiba K; Rosales, Corina; Xu, Bingqing; Gotto, Antonio M; Pownall, Henry J

2018-04-12

Human plasma high-density lipoprotein cholesterol concentrations are a negative risk factor for atherosclerosis-linked cardiovascular disease. Pharmacological attempts to reduce atherosclerotic cardiovascular disease by increasing plasma high-density lipoprotein cholesterol have been disappointing so that recent research has shifted from HDL quantity to HDL quality, that is, functional vs dysfunctional HDL. HDL has varying degrees of dysfunction reflected in impaired reverse cholesterol transport (RCT). In the context of atheroprotection, RCT occurs by 2 mechanisms: one is the well-known trans-hepatic pathway comprising macrophage free cholesterol (FC) efflux, which produces early forms of FC-rich nascent HDL (nHDL). Lecithin:cholesterol acyltransferase converts HDL-FC to HDL-cholesteryl ester while converting nHDL from a disc to a mature spherical HDL, which transfers its cholesteryl ester to the hepatic HDL receptor, scavenger receptor B1 for uptake, conversion to bile salts, or transfer to the intestine for excretion. Although widely cited, current evidence suggests that this is a minor pathway and that most HDL-FC and nHDL-FC rapidly transfer directly to the liver independent of lecithin:cholesterol acyltransferase activity. A small fraction of plasma HDL-FC enters the trans-intestinal efflux pathway comprising direct FC transfer to the intestine. SR-B1 -/- mice, which have impaired trans-hepatic FC transport, are characterized by high plasma levels of a dysfunctional FC-rich HDL that increases plasma FC bioavailability in a way that produces whole-body hypercholesterolemia and multiple pathologies. The design of future therapeutic strategies to improve RCT will have to be formulated in the context of these dual RCT mechanisms and the role of FC bioavailability. Copyright © 2018 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Influence of moderate physical activity on the levels of plasma lipoproteins in subjects with impaired glucose tolerance

Directory of Open Access Journals (Sweden)

Petković-Košćal Milanka

2012-01-01

Full Text Available Introduction. Physical activity and healthy diet, as lifestyle factors, are essential components in the prevention of chronic noncommunicable diseases. Impared glucose intolerance (IGT is an independent cardiovascular risk factor. Dyslipidaemia is a cardiometabolic risk factor for the development of type 2 diabetes mellitus. Objective. The aim of the study was to investigate the influence of moderate physical activity of plasma lipoprotein indicators in high-risk subjects for diabetes mellitus during one-year planned intervention. Methods. We randomly assigned 60 overweight subjects with IGT aged 30-60 years. The subjects were divided into intervention group with 30 subjects, who were intensively and individually instructed on weight reduction, nutrition and increased physical activity, and control group with 30 subjects, who were counselled, as standard, on nutrition and increased exercise. Total cholesterol (TC, LDL cholesterol (LDL-C, HDL cholesterol (HDL-C and triglycerides (Tg were measured at the beginning of the study, and at 2 months, 6 months, and at the end of the study (12 months. Results. Compared to the beginning of the study, after 2 and 6 months there was no statistically significant difference in serum lipid values. After 12 months, the average values of the measured lipid levels in the intervention group decreased by 18.36% for TC, 27.3% for LDL-C, and 34.2% for Tg (compared to 10.27%, 13.45%, and 10.4%, respectively in the control group. Value of HDL-C in the intervention group increased by 19.12%, and decreased in the control group by 1.48%. Total/HDL-C ratio was reduced by 30.6% and LDL-C/H by 38.1% in the intervention group (compared to 12.36%, and 15.9% in the control group. After 12 months, significantly greater decrease in TC (p<0.01, LDL-C (p<0.01 and Tg (p<0.0001 and significantly greater increase in HDL-C (p<0.05 was detected in the intervention group compared to the control group. Conclusion. Plasma lipoproteins can

Effects of 1,2-cyclohexanedione modification on the metabolism of very low density lipoprotein apolipoprotein B: potential role of receptors in intermediate density lipoprotein catabolism

International Nuclear Information System (INIS)

Packard, C.J.; Boag, D.E.; Clegg, R.; Bedford, D.; Shepherd, J.

1985-01-01

The conversion of very low density (VLDL) to low density lipoproteins (LDL) is a two-step process. The first step is mediated by lipoprotein lipase, but the mechanism responsible for the second is obscure. In this study we examined the possible involvement of receptors at this stage. Apolipoprotein B (apoB)-containing lipoproteins were separated into three fractions, VLDL (Sf 100-400), an intermediate fraction IDL (Sf 12-100), and LDL (Sf 0-12). Autologous 125I-labeled VLDL and 131I-labeled 1,2-cyclohexanedione-modified VLDL were injected into the plasma of four normal subjects and the rate of transfer of apoB radioactivity was followed through IDL to LDL. Modification did not affect VLDL to IDL conversion. Thereafter, however, the catabolism of modified apoB in IDL was retarded and its appearance in LDL was delayed. Hence, functional arginine residues (and by implication, receptors) are required in this process. Confirmation of this was obtained by injecting 125I-labeled IDL and 131I-labeled cyclohexanedione-treated IDL into two additional subjects. Again, IDL metabolism was delayed by approximately 50% as a result of the modification. These data are consistent with the view that receptors are involved in the metabolism of intermediate density lipoprotein

Proteomic Analysis of Plasma-Purified VLDL, LDL, and HDL Fractions from Atherosclerotic Patients Undergoing Carotid Endarterectomy: Identification of Serum Amyloid A as a Potential Marker

Directory of Open Access Journals (Sweden)

Antonio J. Lepedda

2013-01-01

Full Text Available Apolipoproteins are very heterogeneous protein family, implicated in plasma lipoprotein structural stabilization, lipid metabolism, inflammation, or immunity. Obtaining detailed information on apolipoprotein composition and structure may contribute to elucidating lipoprotein roles in atherogenesis and to developing new therapeutic strategies for the treatment of lipoprotein-associated disorders. This study aimed at developing a comprehensive method for characterizing the apolipoprotein component of plasma VLDL, LDL, and HDL fractions from patients undergoing carotid endarterectomy, by means of two-dimensional electrophoresis (2-DE coupled with Mass Spectrometry analysis, useful for identifying potential markers of plaque presence and vulnerability. The adopted method allowed obtaining reproducible 2-DE maps of exchangeable apolipoproteins from VLDL, LDL, and HDL. Twenty-three protein isoforms were identified by peptide mass fingerprinting analysis. Differential proteomic analysis allowed for identifying increased levels of acute-phase serum amyloid A protein (AP SAA in all lipoprotein fractions, especially in LDL from atherosclerotic patients. Results have been confirmed by western blotting analysis on each lipoprotein fraction using apo AI levels for data normalization. The higher levels of AP SAA found in patients suggest a role of LDL as AP SAA carrier into the subendothelial space of artery wall, where AP SAA accumulates and may exert noxious effects.

Contribution of Lipoproteins and Lipoprotein Processing to Endocarditis Virulence in Streptococcus sanguinis▿ §

Science.gov (United States)

Das, Sankar; Kanamoto, Taisei; Ge, Xiuchun; Xu, Ping; Unoki, Takeshi; Munro, Cindy L.; Kitten, Todd

2009-01-01

Streptococcus sanguinis is an important cause of infective endocarditis. Previous studies have identified lipoproteins as virulence determinants in other streptococcal species. Using a bioinformatic approach, we identified 52 putative lipoprotein genes in S. sanguinis strain SK36 as well as genes encoding the lipoprotein-processing enzymes prolipoprotein diacylglyceryl transferase (lgt) and signal peptidase II (lspA). We employed a directed signature-tagged mutagenesis approach to systematically disrupt these genes and screen each mutant for the loss of virulence in an animal model of endocarditis. All mutants were viable. In competitive index assays, mutation of a putative phosphate transporter reduced in vivo competitiveness by 14-fold but also reduced in vitro viability by more than 20-fold. Mutations in lgt, lspA, or an uncharacterized lipoprotein gene reduced competitiveness by two- to threefold in the animal model and in broth culture. Mutation of ssaB, encoding a putative metal transporter, produced a similar effect in culture but reduced in vivo competiveness by >1,000-fold. [3H]palmitate labeling and Western blot analysis confirmed that the lgt mutant failed to acylate lipoproteins, that the lspA mutant had a general defect in lipoprotein cleavage, and that SsaB was processed differently in both mutants. These results indicate that the loss of a single lipoprotein, SsaB, dramatically reduces endocarditis virulence, whereas the loss of most other lipoproteins or of normal lipoprotein processing has no more than a minor effect on virulence. PMID:19395487

Assessing the functional properties of high-density lipoproteins : an emerging concept in cardiovascular research

NARCIS (Netherlands)

Triolo, Michela; Annema, Wijtske; Dullaart, Robin P. F.; Tietge, Uwe J. F.

Although plasma concentrations of high-density lipoprotein (HDL) cholesterol correlate inversely with the incidence of atherosclerotic cardiovascular disease, results from recent epidemiological, genetic and pharmacological intervention studies resulted in a shift of concept. Rather than HDL

The effect of omega-3 carboxylic acids on apolipoprotein CIII-containing lipoproteins in severe hypertriglyceridemia.

Science.gov (United States)

Morton, Allyson M; Furtado, Jeremy D; Lee, Jane; Amerine, William; Davidson, Michael H; Sacks, Frank M

Lipoprotein subspecies containing apoCIII adversely affect cardiovascular disease (CVD) risk; for example, low density lipoprotein (LDL) with apoCIII is a stronger CVD predictor than LDL without apoCIII. The Epanova for Lowering Very High Triglycerides (EVOLVE) trial showed that Epanova (omega-3 carboxylic acids [OM3-CA]) significantly lowered TG and apoCIII but raised LDL-C. However, it is unknown what subspecies of LDL were affected by treatment. To determine how lipoprotein subspecies are affected by omega-3 fatty acid treatment, we studied the effect of OM3-CA on apoCIII concentrations in high density lipoprotein (HDL), LDL, and very low density lipoprotein (VLDL) and on the concentrations of subspecies of HDL, LDL, and VLDL that contain or do not contain apoCIII. We analyzed plasma from a subset of subjects from the EVOLVE trial, a 12-week double-blind study of 399 subjects with fasting TG of 500 to 2000 mg/dL who were randomized to OM3-CA 2, 3, or 4 g/d or olive oil (placebo). OM3-CA significantly reduced plasma apoCIII relative to placebo, as well as apoCIII in HDL, and apoCIII in LDL. Treatment did not significantly affect the concentration of LDL with apoCIII, a subspecies highly associated with CVD risk. OM3-CA increased selectively the concentration of LDL that does not contain apoCIII, a subspecies with a weak relation to coronary heart disease. The reduction in apoCIII was associated with plasma increases in eicosapentaenoic acid, docosahexaenoic acid, and arachidonic acid and decreases in linoleic, palmitic, and oleic acids. Reduction in apoCIII may be a mechanism for the TG-lowering effects of OM3-CA. The increase in LDL-C seen in the EVOLVE trial may not be associated with increased risk of CVD. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Low density lipoprotein for oxidation and metabolic studies. Isolation from small volumes of plasma using a tabletop ultracentrifuge.

Science.gov (United States)

Himber, J; Bühler, E; Moll, D; Moser, U K

1995-01-01

A rapid method is described for the isolation of small volumes of plasma low density lipoprotein (LDL) free of plasma protein contaminants using the TL-100 Tabletop Ultracentrifuge (Beckman). The isolation of LDL was achieved by a 25 min discontinuous gradient density centrifugation between the density range of 1.006 and 1.21 g/ml, recovery of LDL by tube slicing followed by a 90 min flotation step (d = 1.12 g/ml). The purity of LDL and apolipoprotein B100 (apo B100) were monitored by agarose electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), radial immunodiffusion and micropreparative fast protein liquid chromatography (FPLC). The ability of LDL oxidation was assessed by following absorbance at 234 nm after addition of copper ions. The functional integrity of the isolated LDL was checked by clearance kinetics after injection of [125I]-labelled LDL in estrogen-treated rats. The additional purification step led to LDL fractions free of protein contamination and left apo B100, alpha-tocopherol and beta-carotene intact. The LDL prepared in this way was free of albumin, as evident from analytic tests and from its enhanced oxidative modification by copper ions. Used for analytical purposes, this method allows LDL preparations from plasma volumes up to 570 microliters. This method is also convenient for metabolic studies in small animals, especially those relating to the determination of kinetic parameters of LDL in which LDL-apo B100 has to be specifically radiolabelled.

Postprandial triglyceride-rich lipoproteins regulate perilipin-2 and perilipin-3 lipid-droplet-associated proteins in macrophages.

Science.gov (United States)

Varela, Lourdes M; López, Sergio; Ortega-Gómez, Almudena; Bermúdez, Beatriz; Buers, Insa; Robenek, Horst; Muriana, Francisco J G; Abia, Rocío

2015-04-01

Lipid accumulation in macrophages contributes to atherosclerosis. Within macrophages, lipids are stored in lipid droplets (LDs); perilipin-2 and perilipin-3 are the main LD-associated proteins. Postprandial triglyceride (TG)-rich lipoproteins induce LD accumulation in macrophages. The role of postprandial lipoproteins in perilipin-2 and perilipin-3 regulation was studied. TG-rich lipoproteins (TRLs) induced the levels of intracellular TGs, LDs and perilipin-2 protein expression in THP-1 macrophages and in Apoe(-/-) mice bone-marrow-derived macrophages with low and high basal levels of TGs. Perilipin-3 was only synthesized in mice macrophages with low basal levels of TGs. The regulation was dependent on the fatty acid composition of the lipoproteins; monounsaturated and polyunsaturated fatty acids (PUFAs) more strongly attenuated these effects compared with saturated fatty acids. In THP-1 macrophages, immunofluorescence microscopy and freeze-fracture immunogold labeling indicated that the lipoproteins translocated perilipin-3 from the cytoplasm to the LD surface; only the lipoproteins that were rich in PUFAs suppressed this effect. Chemical inhibition showed that lipoproteins induced perilipin-2 protein expression through the peroxisome proliferator-activated nuclear receptor (PPAR) PPARα and PPARγ pathways. Overall, our data indicate that postprandial TRLs may be involved in atherosclerotic plaque formation through the regulation of perilipin-2 and perilipin-3 proteins in macrophages. Because the fatty acid composition of the lipoproteins is dependent on the type of fat consumed, the ingestion of olive oil, which is rich in monounsaturated fatty acids, and fish oil, which is rich in omega-3 fatty acids, can be considered a good nutritional strategy to reduce the risk of atherosclerosis by LD-associated proteins decrease. Copyright © 2015 Elsevier Inc. All rights reserved.

Biomedicinal implications of high-density lipoprotein: its composition, structure, functions, and clinical applications.

Science.gov (United States)

Cho, Kyung-Hyun

2009-07-31

High-density lipoprotein (HDL) is a proven biomarker for the monitoring of changes in antioxidant and anti-inflammation capability of body fluids. The beneficial virtues of HDL are highly dependent on its lipids and protein compositions, and their ratios. In normal state, the HDL particle is enriched with lipids and several HDL-associated enzymes, which are responsible for its antioxidant activity. Lower HDL-cholesterol levels (40 mg/dL) have been recognized as an independent risk factor for coronary artery disease, as well as being a known component of metabolic syndrome. Functional and structural changes of HDL have been recognized as factors pivotal to the evaluation of HDL-quality. In this review, I have elected to focus on the functional and structural correlations of HDL and the roles of HDL-associated apolipoproteins and enzymes. Recent clinical applications of HDL have also been reviewed, particularly the therapeutic targeting of HDL metabolism and reconstituted HDL; these techniques represent promising emerging strategies for the treatment of cardiovascular disease, for drug or gene therapy.

Characterization of Mullite-Zirconia Composite Processed by Non-Transferred and Transferred Arc Plasma

International Nuclear Information System (INIS)

Yugeswaran, S.; Selvarajan, V.; Lusvarghi, L.; Tok, A. I. Y.; Krishna, D. Siva Rama

2009-01-01

The arc plasma melting technique is a simple method to synthesize high temperature reaction composites. In this study, mullite-zirconia composite was synthesized by transferred and non-transferred arc plasma melting, and the results were compared. A mixture of alumina and zircon powders with a mole ratio of 3: 2 were ball milled for four hours and melted for two minutes in the transferred and non-transferred mode of plasma arcs. Argon and air were used as plasma forming gases. The phase and microstructural formation of melted samples were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The microstructure of the composites was found to be affected by the mode of melting. In transferred arc melting, zirconia flowers with uniform lines along with mullite whiskers were obtained. In the case of non-transferred arc plasma melting, mullite whiskers along with star shape zirconia were formed. Differential thermal analysis (DTA) of the synthesized mullite-zirconia composites provided a deeper understanding of the mechanisms of mullite formation during the two different processes. (plasma technology)

Effects of oxygen plasma treatment power on Aramid fiber III/BMI composite humidity resistance properties

Science.gov (United States)

Wang, Jing; Shi, Chen; Feng, Jiayue; Long, Xi; Meng, Lingzhi; Ren, Hang

2018-01-01

The effects of oxygen plasma treatment power on Aramid Fiber III chemical structure and its reinforced bismaleimides (BMI) composite humidity resistance properties were investigated in this work. The aramid fiber III chemical structure under different plasma treatment power were measured by FTIR. The composite bending strength and interlinear shear strength with different plasma treatment power before and after absorption water were tested respectively. The composite rupture morphology was observed by SEM. The FTIR results showed that oxygen plasma treatment do not change the fiber bulk chemical structure. The composite humidity resistance of bending strength and interlinear shear strength are similar for untreated and plasma treated samples. The retention rate of composite bending strength and interlinear shear strength are about 75% and 94%, respectively. The composite rupture mode turns to be the fiber failure after water absorption.

Effect of phospholipase A treatment of low density lipoproteins on the dextran sulfate--lipoprotein interaction.

Science.gov (United States)

Nishida, T

1968-09-01

The effect of phospholipase A on the interaction of low density lipoproteins of the S(f) 0-10 class with dextran sulfate was studied in phosphate buffer of pH 7.4, ionic strength 0.1, by chemical, spectrophotometric, and centrifugal methods. When low density lipoproteins that had been treated with phospholipase A were substituted for untreated lipoproteins, the amount of insoluble dextran sulfate-lipoprotein complex formed was greatly reduced. Hydrolysis of over 20% of the lecithin and phosphatidyl ethanolamine constituents of the lipoproteins prevented the formation of insoluble complex. However, even the lipoproteins in which almost all the phosphoglycerides were hydrolyzed produced soluble complex, which was converted to insoluble complex upon addition of magnesium sulfate. It is apparent that the lipoproteins altered extensively by treatment with phospholipase A retain many characteristic properties of native low density lipoproteins. Fatty acids, but not lysolecithin, released by the action of phospholipase A interfered with the formation of insoluble complex; this interference was due to association of the fatty acids with the lipoproteins. With increases in the concentration of the associated fatty acids, the amounts of magnesium ion required for the conversion of soluble complex to insoluble complex increased progressively. Charge interaction is evidently of paramount importance in the formation of sulfated polysaccharide-lipoprotein complexes.

Non-leaky vesiculation of large unilamellar vesicles (LUV) induced by plasma high density lipoproteins (HDL): Detection by HPLC

International Nuclear Information System (INIS)

Tischler, U.; Rueckert, D.S.; Schubert, R.; Jaroni, H.W.; Schmidt, K.H.

1989-01-01

Interaction of large unilamellar phosphatidylcholine vesicles (LUV, 75nm) and plasma high density lipoproteins (HDL) resulted in a non-leaky vesiculation of LUV. This vesiculation was detected by a HPLC-system consisting of a combination of three TSK-gel columns (6000PW, 5000PW, 3000SW). With increasing incubation time liposomal [ 14 C]PC, entrapped [ 3 H]inulin, and apoprotein of HDL origin decreased. The decrease was accompanied by a formation of new particles, consisting of liposomal PC and apoprotein. These particles also enclosed [3H]inulin, reflecting a hydrophilic inner space. The formation of the particles reached a maximum after one day of incubation. Retention time was 21 minutes for LUV, 28 minutes for the new particles, and 36 minutes for HDL. In vesicles with membranes consisting of phosphatidylcholine and 30% cholesterol no interactions were observed

Production of oxide-metal P/M composites using pulsed plasma heating

Energy Technology Data Exchange (ETDEWEB)

Blinkov, I.V.; Manukhin, A.V.; Ostapovich, A.O.; Pavlov, IU.A.

1987-08-01

The possibility of producing oxide-metal P/M composites using plasma generated by a pulsed discharge is investigated experimentally for the system Al/sup 2/O/sub 3/-Ni. It is found that Al/sup 2/O/sub 3/ metallization in plasma is accompanied by spheroidization; changes in the physicomechanical properties of the Al/sup 2/O/sub 3/-Ni composite during plasma treatment are examined. The characteristic features of the process associated with the effect of pulsed energy on the disperse flow of the oxide-metal mixture are discussed. 7 references.

Diffusion in plasma: The Hall effect, compositional waves, and chemical spots

Energy Technology Data Exchange (ETDEWEB)

Urpin, V., E-mail: Vadim.urpin@uv.es [Ioffe Institute of Physics and Technology (Russian Federation)

2017-03-15

Diffusion caused by a combined influence of the electric current and Hall effect is considered, and it is argued that such diffusion can form inhomogeneities of a chemical composition in plasma. The considered mechanism can be responsible for the formation of element spots in laboratory and astrophysical plasmas. This current-driven diffusion can be accompanied by propagation of a particular type of waves in which the impurity number density oscillates alone. These compositional waves exist if the magnetic pressure in plasma is much greater than the gas pressure.

High density lipoprotein as a source of cholesterol for adrenal steroidogenesis: a study in individuals with low plasma HDL-C

NARCIS (Netherlands)

Bochem, Andrea E.; Holleboom, Adriaan G.; Romijn, Johannes A.; Hoekstra, Menno; Dallinga-Thie, Geesje M.; Motazacker, Mahdi M.; Hovingh, G. Kees; Kuivenhoven, Jan A.; Stroes, Erik S. G.

2013-01-01

Few studies have addressed the delivery of lipoprotein-derived cholesterol to the adrenals for steroid production in humans. While there is evidence against a role for low-density lipoprotein (LDL), it is unresolved whether high density lipoprotein (HDL) contributes to adrenal steroidogenesis. To

Consolidation of W–Ta composites: Hot isostatic pressing and spark and pulse plasma sintering

Energy Technology Data Exchange (ETDEWEB)

Dias, M., E-mail: marta.dias@itn.pt [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Guerreiro, F. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Correia, J.B. [LNEG, Laboratório Nacional de Energia e Geologia, Estrada do Paço do Lumiar, 1649-038 Lisboa (Portugal); Galatanu, A. [National Institute of Materials Physics, Atomistilor 105 bis Bucharest-Magurele, 077125 Ilfov (Romania); Rosiński, M. [Warsaw University of Technology, Faculty of Materials Science and Engineering, Warsaw (Poland); Monge, M.A.; Munoz, A. [Departamento de Física, Univerdidad Carlos III de Madrid, Avd. de la Universidad 30, 28911 Madrid (Spain); Alves, E. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Carvalho, P.A. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); CeFEMA, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal)

2015-10-15

Highlights: • Consolidation of W–Ta composites using three techniques: HIP, SPS and PPS. • Comparison of consolidation methods in terms of W–Ta interdiffusion and densification. • Microstructure analysis in terms of oxides formation. - Abstract: Composites consisting of tantalum fiber/powder dispersed in a nanostructured W matrix have been consolidated by spark and pulse plasma sintering as well as by hot isostatic pressing. The microstructural observations revealed that the tungsten–tantalum fiber composites consolidated by hot isostatic pressing and pulse plasma sintering presented a continuous layer of Ta{sub 2}O{sub 5} phase at the W/Ta interfaces, while the samples consolidated by spark plasma sintering evidenced a Ta + Ta{sub 2}O{sub 5} eutectic mixture due to the higher temperature of this consolidation process. Similar results have been obtained for the tungsten–tantalum powder composites. A (W, Ta) solid solution was detected around the prior nanostructured W particles in tungsten–tantalum powder composites consolidated by spark and pulse plasma sintering. Higher densifications were obtained for composites consolidated by hot isostatic pressing and pulse plasma sintering.

Transvascular low-density lipoprotein transport in patients with diabetes mellitus (type 2)

DEFF Research Database (Denmark)

Kornerup, Karen; Nordestgaard, Børge Grønne; Feldt-Rasmussen, Bo

2002-01-01

accumulation and, thus, atherosclerosis. METHODS AND RESULTS: We developed an in vivo method for measurement of transvascular transport of low density lipoprotein (LDL) and applied it in 16 patients with maturity-onset diabetes (type 2) and 29 healthy control subjects. Autologous 131I-labeled LDL...... plasma insulin levels in diabetic patients. CONCLUSIONS: Transvascular LDL transport may be increased in patients with type 2 diabetes. This suggests that lipoprotein flux into the arterial wall is increased in people with diabetes, possibly explaining the accelerated development of atherosclerosis....... in patients with diabetes and control subjects, respectively (P2.5%/h and 5.3+/-1.6%/h (P

High density lipoprotein is an inappropriate substrate for hepatic lipase in postmenopausal women.

Science.gov (United States)

Zago, Valeria; Miksztowicz, Verónica; Cacciagiú, Leonardo; Basilio, Francisco; Berg, Gabriela; Schreier, Laura

2012-12-24

HDL antiatherogenic effects would not only depend on its concentration but also on its biological quality. Hepatic lipase (HL) action on HDL acts in one of the last steps of reverse cholesterol transport. Cardiovascular risk increases after menopause, however HDL does not decrease even when HL is increased. We evaluated HDL capacity as a substrate of HL in healthy postmenopausal women (PMW). We studied 20 PMW (51-60 y) and 20 premenopausal (PreMW) (26-40 y). In fasting serum, lipid-lipoprotein profile and HDL composition were assessed. Optimal assay conditions for HDL/HL ex vivo incubation were established. Increasing HDL-triglyceride concentrations (0.015 to 0.20 mmol/l) were incubated with post-heparin plasma obtained from a single healthy donor as a source of HL. Free fatty acids were measured and kinetic parameters calculated: K(m)(app), inverse to enzyme affinity, and V(max). HDL composition in PMW exhibits triglyceride enrichment (p<0.001). Kinetic analysis revealed higher K(m)(app) in PMW [130 (40-380) vs 45 (20-91) mmol/l, p<0.0001)] correlating directly with HDL-triglycerides (r=0.7, p=0.0001). Catalytic efficiency, V(max)/K(m)(app) was reduced when compared to controls (p=0.0001). Triglyceride-enriched HDL from PMW constitutes a poor substrate for HL suggesting that this particle may not exert efficiently its antiatherogenic function, regardless of plasma concentration. Copyright © 2012 Elsevier B.V. All rights reserved.

Serum lipoprotein (a) concentration in patients with nephrotic syndrome and its clinical implication.

Science.gov (United States)

Yang, X; Wang, H; Zhu, Z; Deng, A

1998-01-01

Serum lipoprotein(a) [Lp(a)] concentration was determined in 42 patients with primary nephrotic syndrome (NS) and the relationships between Lp (a) and plasma lipids, apolipoproteins, serum creatinine (Scr), albumin, urinary proteins (Upro) were also analyzed. The results showed that: (1) serum Lp(a) concentrations in the patients with NS were higher than those in healthy controls; (2) the levels of serum Lp(a) were correlated positively with total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), apolipoprotein B (Apo-B), Upros (Upro). It is concluded that the NS patients had the potential risk of suffering from coronary artery disease, glomerular sclerosis and thrombosis. The remission of NS may partially decrease the serum Lp(a) levels. Further studies are needed to explore the prevention and treatment of dislipedemia in patients with NS.

Adhesion enhancement of Al coatings on carbon/epoxy composite surfaces by atmospheric plasma

International Nuclear Information System (INIS)

Coulon, J.F.; Tournerie, N.; Maillard, H.

2013-01-01

Adhesion strengths between aluminium thin film coatings and manufactured carbon/epoxy composite surfaces were measured by assessing fracture tensile strengths using pull-off tests. The effect of the substrate roughness (nm to μm) of these composite surfaces on adhesion was studied by examining the surface free energies and adhesion strengths. The adhesion strengths of the coatings varied significantly. To improve the coating adhesion, each composite surface was treated with atmospheric plasma prior to deposition, which resulted in an increase in the surface free energy from approximately 40 mJ/m 2 to 70 mJ/m 2 because the plasma pretreatment led to the formation of hydrophilic C-O and C=O bonds on the composite surfaces, as demonstrated by X-ray photoelectron spectroscopy analyses. The adhesion strengths of the coatings were enhanced for all surface roughnesses studied. In our study, the effect of mechanical adhesion due to roughness was separated from the effect of modifying the chemical bonds with plasma activation. The adhesion ability of the pure resin was relatively weak. Increasing the surface roughness largely improved the adhesion of the resin surface. Plasma treatment of the pure resin also increased the surface adhesion. Our study shows that plasma activation effectively enhances the adhesion of manufactured composites, even when the surface roughness is on the order of microns. The ageing of the surface activation was also investigated, and the results demonstrate that atmospheric plasma has potential for use in the pretreatment of composite materials.

Effect of omega-3 fatty acids on the oxylipin composition of lipoproteins in hypertriglyceridemic, statin-treated subjects

Science.gov (United States)

Background: Oxylipins mediate many physiological processes, including inflammation and vascular function. Generally considered local and transient, we suggest their presence in lipoproteins indicates they also mediate the effects lipoproteins have on inflammation and vascular biology. To support th...

Mechanical properties of epoxy composites with plasma-modified rice-husk-derived nanosilica

Science.gov (United States)

Hubilla, Fatima Athena D.; Panghulan, Glenson R.; Pechardo, Jason; Vasquez, Magdaleno R., Jr.

2018-01-01

In this study, we explored the use of rice-husk-derived nanosilica (nSiO2) as fillers in epoxy resins. The nSiO2 was irradiated with a capacitively coupled 13.56 MHz radio frequency (RF) plasma using an admixture of argon (Ar) and hexamethyldisiloxane (HMDSO) or 1,7-octadiene (OD) monomers. The plasma-polymerized nSiO2 was loaded at various concentrations (1-5%) into the epoxy matrix. Surface hydrophobicity of the plasma-treated nSiO2-filled composites increased, which is attributed to the attachment of functional groups from the monomer gases on the silica surface. Microhardness increased by at least 10% upon the inclusion of plasma-modified nSiO2 compared with pristine nSiO2-epoxy composites. Likewise, hardness increased with increasing loading volume, with the HMDSO-treated silica composite recording the highest increase. Elastic moduli of the composites also showed an increase of at least 14% compared with untreated nSiO2-filled composites. This work demonstrated the use of rice husk, an agricultural waste, as a nSiO2 source for epoxy resin fillers.

Biogenesis and Membrane Targeting of Lipoproteins.

Science.gov (United States)

Narita, Shin-Ichiro; Tokuda, Hajime

2010-09-01

Bacterial lipoproteins represent a unique class of membrane proteins, which are anchored to membranes through triacyl chains attached to the amino-terminal cysteine. They are involved in various functions localized in cell envelope. Escherichia coli possesses more than 90 species of lipoproteins, most of which are localized in the outer membrane, with others being in the inner membrane. All lipoproteins are synthesized in the cytoplasm with an N-terminal signal peptide, translocated across the inner membrane by the Sec translocon to the periplasmic surface of the inner membrane, and converted to mature lipoproteins through sequential reactions catalyzed by three lipoprotein-processing enzymes: Lgt, LspA, and Lnt. The sorting of lipoproteins to the outer membrane requires a system comprising five Lol proteins. An ATP-binding cassette transporter, LolCDE, initiates the sorting by mediating the detachment of lipoproteins from the inner membrane. Formation of the LolA-lipoprotein complex is coupled to this LolCDE-dependent release reaction. LolA accommodates the amino-terminal acyl chain of lipoproteins in its hydrophobic cavity, thereby generating a hydrophilic complex that can traverse the periplasmic space by diffusion. Lipoproteins are then transferred to LolB on the outer membrane and anchored to the inner leaflet of the outer membrane by the action of LolB. In contrast, since LolCDE does not recognize lipoproteins possessing Asp at position +2, these lipoproteins remain anchored to the inner membrane. Genes for Lol proteins are widely conserved among gram-negative bacteria, and Lol-mediated outer membrane targeting of lipoproteins is considered to be the general lipoprotein localization mechanism.

Triglyceride-rich lipoproteins as a causal factor for cardiovascular disease

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Toth PP

2016-05-01

Full Text Available Peter P Toth1,2 1Ciccarone Center for the Prevention of Cardiovascular Disease, Johns Hopkins University School of Medicine, Baltimore, MD, 2Preventive Cardiology, CGH Medical Center, Sterling, IL, USA Abstract: Approximately 25% of US adults are estimated to have hypertriglyceridemia (triglyceride [TG] level ≥150 mg/dL [≥1.7 mmol/L]. Elevated TG levels are associated with increased cardiovascular disease (CVD risk, and severe hypertriglyceridemia (TG levels ≥500 mg/dL [≥5.6 mmol/L] is a well-established risk factor for acute pancreatitis. Plasma TG levels correspond to the sum of the TG content in TG-rich lipoproteins (TRLs; ie, very low-density lipoproteins plus chylomicrons and their remnants. There remains some uncertainty regarding the direct causal role of TRLs in the progression of atherosclerosis and CVD, with cardiovascular outcome studies of TG-lowering agents, to date, having produced inconsistent results. Although low-density lipoprotein cholesterol (LDL-C remains the primary treatment target to reduce CVD risk, a number of large-scale epidemiological studies have shown that elevated TG levels are independently associated with increased incidence of cardiovascular events, even in patients treated effectively with statins. Genetic studies have further clarified the causal association between TRLs and CVD. Variants in several key genes involved in TRL metabolism are strongly associated with CVD risk, with the strength of a variant's effect on TG levels correlating with the magnitude of the variant's effect on CVD. TRLs are thought to contribute to the progression of atherosclerosis and CVD via a number of direct and indirect mechanisms. They directly contribute to intimal cholesterol deposition and are also involved in the activation and enhancement of several proinflammatory, proapoptotic, and procoagulant pathways. Evidence suggests that non-high-density lipoprotein cholesterol, the sum of the total cholesterol carried by

Inhibition of endothelial lipase activity by sphingomyelin in the lipoproteins.

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Yang, Peng; Belikova, Natalia A; Billheimer, Jeff; Rader, Daniel J; Hill, John S; Subbaiah, Papasani V

2014-10-01

Endothelial lipase (EL) is a major determinant of plasma HDL concentration, its activity being inversely proportional to HDL levels. Although it is known that it preferentially acts on HDL compared to LDL and VLDL, the basis for this specificity is not known. Here we tested the hypothesis that sphingomyelin, a major phospholipid in lipoproteins is a physiological inhibitor of EL, and that the preference of the enzyme for HDL may be due to low sphingomyelin/phosphatidylcholine (PtdCho) ratio in HDL, compared to other lipoproteins. Using recombinant human EL, we showed that sphingomyelin inhibits the hydrolysis of PtdCho in the liposomes in a concentration-dependent manner. While the enzyme showed lower hydrolysis of LDL PtdCho, compared to HDL PtdCho, this difference disappeared after the degradation of lipoprotein sphingomyelin by bacterial sphingomyelinase. Analysis of molecular species of PtdCho hydrolyzed by EL in the lipoproteins showed that the enzyme preferentially hydrolyzed PtdCho containing polyunsaturated fatty acids (PUFA) such as 22:6, 20:5, 20:4 at the sn-2 position, generating the corresponding PUFA-lyso PtdCho. This specificity for PUFA-PtdCho species was not observed after depletion of sphingomyelin by sphingomyelinase. These results show that sphingomyelin not only plays a role in regulating EL activity, but also influences its specificity towards PtdCho species.

Towards Enhanced Performance Thin-film Composite Membranes via Surface Plasma Modification

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Reis, Rackel; Dumée, Ludovic F.; Tardy, Blaise L.; Dagastine, Raymond; Orbell, John D.; Schutz, Jürg A.; Duke, Mikel C.

2016-01-01

Advancing the design of thin-film composite membrane surfaces is one of the most promising pathways to deal with treating varying water qualities and increase their long-term stability and permeability. Although plasma technologies have been explored for surface modification of bulk micro and ultrafiltration membrane materials, the modification of thin film composite membranes is yet to be systematically investigated. Here, the performance of commercial thin-film composite desalination membranes has been significantly enhanced by rapid and facile, low pressure, argon plasma activation. Pressure driven water desalination tests showed that at low power density, flux was improved by 22% without compromising salt rejection. Various plasma durations and excitation powers have been systematically evaluated to assess the impact of plasma glow reactions on the physico-chemical properties of these materials associated with permeability. With increasing power density, plasma treatment enhanced the hydrophilicity of the surfaces, where water contact angles decreasing by 70% were strongly correlated with increased negative charge and smooth uniform surface morphology. These results highlight a versatile chemical modification technique for post-treatment of commercial membrane products that provides uniform morphology and chemically altered surface properties. PMID:27363670

Microwave and plasma-assisted modification of composite fiber surface topography

Science.gov (United States)

Paulauskas, Felix L [Knoxville, TN; White, Terry L [Knoxville, TN; Bigelow, Timothy S [Knoxville, TN

2003-02-04

The present invention introduces a novel method for producing an undulated surface on composite fibers using plasma technology and microwave radiation. The undulated surface improves the mechanical interlocking of the fibers to composite resins and enhances the mechanical strength and interfacial sheer strength of the composites in which they are introduced.

Intercorrelations among plasma high density lipoprotein, obesity and triglycerides in a normal population.

Science.gov (United States)

Albrink, M J; Krauss, R M; Lindgrem, F T; von der Groeben, J; Pan, S; Wood, P D

1980-09-01

The interrelationships among fatness measures, plasma triglycerides and high density lipoproteins (HDL) were examined in 131 normal adult subjects: 38 men aged 27-46, 40 men aged 47-66, 29 women aged 27-46 and 24 women aged 47-66. None of the women were taking estrogens or oral contraceptive medication. The HDL concentration was subdivided into HDL2b, HDL2a and HDL3 by a computerized fitting of the total schlieren pattern to reference schlieren patterns. Anthropometric measures employed included skinfolds at 3 sites. 2 weight/height indices and 2 girth measurements. A high correlation was found among the various fatness measures. These measures were negatively correlated with total HDL, reflecting the negative correlation between fatness measures and HDL2 (as the sum of HDL2a and 2b). Fatness measures showed no relationship to HDL3. There was also an inverse correlation between triglyceride concentration and HDL2. No particular fatness measure was better than any other for demonstrating the inverse correlation with HDL but multiple correlations using all of the measures of obesity improved the correlations. Partial correlations controlling for fatness did not reduce any of the significant correlations between triglycerides and HDL2 to insignificance. The weak correlation between fatness and triglycerides was reduced to insignificance when controlled for HDL2.

Increased fluidity and oxidation of malarial lipoproteins: relation with severity and induction of endothelial expression of adhesion molecules

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Looareesuwan Sornchai

2004-06-01

Full Text Available Abstract Introduction Oxidative stress has been demonstrated in malaria. The potential oxidative modification of lipoproteins derived from malaria patients was studied. These oxidized lipids may have role in pathogenesis of malaria. Method The plasma lipid profile and existence of oxidized forms of very low density lipoprotein (VLDL, low density lipoprotein (LDL and high density lipoprotein (HDL were investigated in malaria (17 mild and 24 severe patients and 37 control subjects. Thiobarbituric acid reactive substances (TBARs, conjugated dienes, tryptophan fluorescence and fluidity of lipoproteins were determined as markers of oxidation. The biological effect of malarial lipoproteins was assessed by the expression of adhesion molecules on endothelial cells. Results Malarial lipoproteins had decreased cholesterol (except in VLDL and phospholipid. The triglyceride levels were unchanged. The cholesterol/phospholipid ratio of LDL was decreased in malaria, but increased in VLDL and HDL. TBARs and conjugate dienes were increased in malarial lipoproteins, while the tryptophan fluorescence was decreased. The fluidity of lipoproteins was increased in malaria. These indicated the presence of oxidized lipoproteins in malaria by which the degree of oxidation was correlated with severity. Of three lipoproteins from malarial patients, LDL displayed the most pronounced oxidative modification. In addition, oxidized LDL from malaria patients increased endothelial expression of adhesion molecules. Conclusion In malaria, the lipoproteins are oxidatively modified, and the degree of oxidation is related with severity. Oxidized LDL from malarial patients increases the endothelial expression of adhesion molecules. These suggest the role of oxidized lipoproteins, especially LDL, on the pathogenesis of disease.

Lipoprotein(a) levels, apo(a) isoform size, and coronary heart disease risk in the Framingham Offspring Study

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The aim of this study was to assess the independent contributions of plasma levels of lipoprotein(a) [Lp(a)], Lp(a) cholesterol, and of apo(a) isoform size to prospective coronary heart disease (CHD) risk. Plasma Lp(a) and Lp(a) cholesterol levels, and apo(a) isoform size were measured at examinati...

Alterations in lipoprotein homeostasis during human experimental endotoxemia and clinical sepsis

NARCIS (Netherlands)

Levels, Johannes H. M.; Pajkrt, Dasja; Schultz, Marcus; Hoek, Frans J.; van Tol, Arie; Meijers, Joost C. M.; van Deventer, Sander J. H.

2007-01-01

Cell wall constituents of bacteria are potent endotoxins initiating inflammatory responses which may cause dramatic changes in lipid metabolism during the acute phase response. In this study, the sequential changes in lipoprotein composition and lipid transfer and binding proteins during clinical

Hemocompatibility and cytocompatibility of pristine and plasma-treated silver-zeolite-chitosan composites

Science.gov (United States)

Taaca, Kathrina Lois M.; Vasquez, Magdaleno R.

2018-02-01

Silver-exchanged zeolite-chitosan (AgZ-Ch) composites with varying AgZ content were prepared by solvent casting and modified under argon (Ar) plasma excited by a 13.56 MHz radio frequency (RF) power source. Silver (Ag) was successfully incorporated in a natural zeolite host without losing its antibacterial activity against Escherichia coli and Staphylococcus aureus. The AgZ particles were incorporated into a chitosan matrix without making significant changes in the matrix structure. The composites also exhibited antibacterial sensitivity due to the inclusion of AgZ. Plasma treatment enhanced the surface wettability of polar and nonpolar test liquids of the composites. The average increase in total surface free energy after treatment was around 49% with the polar component having a significant change. Cytocompatibility tests showed at least 87% cell viability for pristine and plasma-treated composites comparable with supplemented RPMI as positive control. Hemocompatibility tests revealed that pristine composites does not promote hemolysis and the blood clotting ability is less than 10 min. Coupled with antibacterial property, the fabricated composites have promising biomedical applications.

Plasma Lipoprotein-associated Phospholipase A2 in Patients with Metabolic Syndrome and Carotid Atherosclerosis

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Mao Yong-jun

2011-01-01

Full Text Available Abstract Background Lipoprotein-associated phospholipase A2 (Lp-PLA2 is a recently identified and potentially useful plasma biomarker for cardiovascular and atherosclerotic diseases. However, the correlation between the Lp-PLA2 activity and carotid atherosclerosis remains poorly investigated in patients with metabolic syndrome (MetS. The present study aimed to evaluate the potential role of Lp-PLA2 as a comprehensive marker of metabolic syndrome in individuals with and without carotid atherosclerosis. Methods We documented 118 consecutive patients with MetS and 70 age- and sex-matched healthy subjects served as controls. The patients were further divided into two groups: 39 with carotid plaques and 79 without carotid plaques to elucidate the influence of Lp-PLA2 on carotid atherosclerosis. The plasma Lp-PLA2 activity was measured by using ELISA method and carotid intimal-media thickness (IMT was performed by ultrasound in all participants. Results Lp-PLA2 activity was significantly increased in MetS subgroups when compared with controls, and was higher in patients with carotid plaques than those without plaques (P 2 was obtained between patients with three and four disorders of metabolic syndrome (P P = 0.029, LDL-cholesterol (β = 0.401, P = 0.000 and waist-hip ratio (β = 0.410, P = 0.000 emerged as significant and independent determinants of Lp-PLA2 activity. Multiple stepwise regression analysis revealed that LDL-cholesterol (β = 0.309, P = 0.000, systolic blood pressure (β = 0.322, P = 0.002 and age (β = 0.235, P = 0.007 significantly correlated with max IMT, and Lp-PLA2 was not an independent predictor for carotid IMT. Conclusions Lp-PLA2 may be a modulating factor for carotid IMT via age and LDL-cholesterol, not independent predictor in the pathophysiological process of carotid atherosclerosis in patients with MetS.

Single-Particle Tracking of Human Lipoproteins.

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de Messieres, Michel; Ng, Abby; Duarte, Cornelio J; Remaley, Alan T; Lee, Jennifer C

2016-01-05

Lipoproteins, such as high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very-low density lipoprotein (VLDL), play a critical role in heart disease. Lipoproteins vary in size and shape as well as in their apolipoprotein content. Here, we developed a new experimental framework to study freely diffusing lipoproteins from human blood, allowing analysis of even the smallest HDL with a radius of 5 nm. In an easily constructed confinement chamber, individual HDL, LDL, and VLDL particles labeled with three distinct fluorophores were simultaneously tracked by wide-field fluorescence microscopy and their sizes were determined by their motion. This technique enables studies of individual lipoproteins in solution and allows characterization of the heterogeneous properties of lipoproteins which affect their biological function but are difficult to discern in bulk studies.

Genetic analysis of long-lived families reveals novel variants influencing high density-lipoprotein cholesterol

DEFF Research Database (Denmark)

Feitosa, Mary F; Wojczynski, Mary K; Straka, Robert

2014-01-01

The plasma levels of high-density lipoprotein cholesterol (HDL) have an inverse relationship to the risks of atherosclerosis and cardiovascular disease (CVD), and have also been associated with longevity. We sought to identify novel loci for HDL that could potentially provide new insights...

Plasma-activated multi-walled carbon nanotube-polystyrene composite substrates for biosensing

International Nuclear Information System (INIS)

Fernandez-Sanchez, Cesar; Orozco, Jahir; Jimenez-Jorquera, Cecilia; Pellicer, Eva; Lechuga, Laura M; Mendoza, Ernest

2009-01-01

Carbon nanotube-polymer composites have shown to be suitable materials for the fabrication of electrochemical transducers. The exposed surface of these materials is commonly passivated by a very thin layer of the polymer component that buries the conductive carbon particles. Working with multi-walled carbon nanotube-polystyrene (MWCNT-PS) composite structures, it was previously described how a simple low power oxygen plasma process produced an effective etching of the composite surface, thereby exposing the conductive surface of CNTs. This work shows how this plasma process not only gave rise to a suitable composite conductive surface for electrochemical sensing but simultaneously exposed and created a high density of oxygen-containing functional groups at both the CNT and the PS components, without affecting the material's mechanical stability. These chemical groups could be effectively modified for the stable immobilization of biological receptors. A detailed chemical characterization of the plasma-activated composite surface was possible using x-ray photoelectron spectroscopy. The material reactivity towards the tethering of a protein was studied and protein-protein interactions were then evaluated on the modified composite transducers by scanning electron microscopy. Finally, an amperometric immunosensor approach for the detection of rabbit Immunoglobulin G target analyte was described and a minimum concentration of 3 ng ml -1 was easily measured.

Plasma-activated multi-walled carbon nanotube-polystyrene composite substrates for biosensing

Energy Technology Data Exchange (ETDEWEB)

Fernandez-Sanchez, Cesar; Orozco, Jahir; Jimenez-Jorquera, Cecilia [Instituto de Microelectronica de Barcelona, IMB-CNM (CSIC), Campus UAB, E-08193 Bellaterra, Barcelona (Spain); Pellicer, Eva; Lechuga, Laura M; Mendoza, Ernest, E-mail: cesar.fernandez@imb-cnm.csic.e [Nanobiosensors and Molecular Nanobiophysics Group, Research Center on Nanoscience and Nanotechnology (CIN2) CSIC-ICN, ETSE, Campus UAB-Edificio Q, E-08193 Bellaterra, Barcelona (Spain)

2009-08-19

Carbon nanotube-polymer composites have shown to be suitable materials for the fabrication of electrochemical transducers. The exposed surface of these materials is commonly passivated by a very thin layer of the polymer component that buries the conductive carbon particles. Working with multi-walled carbon nanotube-polystyrene (MWCNT-PS) composite structures, it was previously described how a simple low power oxygen plasma process produced an effective etching of the composite surface, thereby exposing the conductive surface of CNTs. This work shows how this plasma process not only gave rise to a suitable composite conductive surface for electrochemical sensing but simultaneously exposed and created a high density of oxygen-containing functional groups at both the CNT and the PS components, without affecting the material's mechanical stability. These chemical groups could be effectively modified for the stable immobilization of biological receptors. A detailed chemical characterization of the plasma-activated composite surface was possible using x-ray photoelectron spectroscopy. The material reactivity towards the tethering of a protein was studied and protein-protein interactions were then evaluated on the modified composite transducers by scanning electron microscopy. Finally, an amperometric immunosensor approach for the detection of rabbit Immunoglobulin G target analyte was described and a minimum concentration of 3 ng ml{sup -1} was easily measured.

[Alterations in the protein content and dysfunction of high-density lipoproteins from hyperhomocysteinemic mice].

Science.gov (United States)

Julve, Josep; Errico, Teresa Laura; Chen, Xiangyu; Santos, David; Freixa, Júlia; Porcel, Inmaculada; Cubero, Esther; Escolà-Gil, Joan Carles; Blanco-Vaca, Francisco

2013-01-01

The aim of this study was to evaluate the proteic changes in high-density lipoproteins (HDL) induced by methionine-induced hyperhomocysteinemia in mice and its relationship with two of their main antiatherogenic properties. The oral administration of methionine resulted in an elevation (~8 times) in the plasma concentration of homocysteine. Hyperhomocysteinemia was inversely correlated with the plasma concentration of HDL cholesterol and its main protein component of HDL, apolipoprotein (apo) A-I, respectively. The cholesterol efflux in vivo from macrophages to HDL was decreased in hyperhomocysteinemic mice compared with the control mice. However, the reverse cholesterol transport from macrophages to feces remained unchanged. On the other hand, the ability of HDL from hyperhomocysteinemic mice to prevent the oxidative modification of low-density lipoproteins (LDL) was found decreased and associated with a concomitant reduction in the plasma activity of paraoxonase-1 (PON1) and the plasma concentration of apoA-I, and with a relative reduction in the apoA-IV content (~1.5 times) in the hyperhomocysteinemic HDL, respectively. The decrease in the ability of HDL from hyperhomocysteinemic mice to prevent LDL from oxidation was associated with a decrease in the apoA-I, PON1 and apoA-IV. Copyright © 2013 Elsevier España, S.L. and SEA. All rights reserved.

Combined measurement of plasma cystatin C and low-density lipoprotein cholesterol: A valuable tool for evaluating progressive supranuclear palsy.

Science.gov (United States)

Weng, Ruihui; Wei, Xiaobo; Yu, Bin; Zhu, Shuzhen; Yang, Xiaohua; Xie, Fen; Zhang, Mahui; Jiang, Ying; Feng, Zhong-Ping; Sun, Hong-Shuo; Xia, Ying; Jin, Kunlin; Chan, Piu; Wang, Qing; Gao, Xiaoya

2018-07-01

Progressive supranuclear palsy (PSP) was previously thought as a cause of atypical Parkinsonism. Although Cystatin C (Cys C) and low-density cholesterol lipoprotein-C (LDL-C) are known to play critical roles in Parkinsonism, it is unknown whether they can be used as markers to distinguish PSP patients from healthy subjects and to determine disease severity. We conducted a cross-sectional study to determine plasma Cys C/HDL/LDL-C levels of 40 patients with PSP and 40 healthy age-matched controls. An extended battery of motor and neuropsychological tests, including the PSP-Rating Scale (PSPRS), the Non-Motor Symptoms Scale (NMSS), Geriatric Depression Scale (GDS) and Mini-Mental State Examination (MMSE), was used to evaluate the disease severity. Receiver operating characteristic (ROC) curves were adopted to assess the prognostic accuracy of Cys C/LDL-C levels in distinguishing PSP from healthy subjects. Patients with PSP exhibited significantly higher plasma levels of Cys C and lower LDL-C. The levels of plasma Cys C were positively and inversely correlated with the PSPRS/NMSS and MMSE scores, respectively. The LDL-C/HDL-C ratio was positively associated with PSPRS/NMSS and GDS scores. The ROC curve for the combination of Cys C and LDL-C yielded a better accuracy for distinguishing PSP from healthy subjects than the separate curves for each parameter. Plasma Cys C and LDL-C may be valuable screening tools for differentiating PSP from healthy subjects; while they could be useful for the PSP intensifies and severity evaluation. A better understanding of Cys C and LDL-C may yield insights into the pathogenesis of PSP. Copyright © 2018 Elsevier Ltd. All rights reserved.

Role of Hepatic Lipase and Endothelial Lipase in High-Density Lipoprotein-Mediated Reverse Cholesterol Transport

NARCIS (Netherlands)

Annema, Wijtske; Tietge, Uwe J. F.

Reverse cholesterol transport (RCT) constitutes a key part of the atheroprotective properties of high-density lipoproteins (HDL). Hepatic lipase (HL) and endothelial lipase (EL) are negative regulators of plasma HDL cholesterol levels. Although overexpression of EL decreases overall

Lipoprotein glomerulopathy treated with LDL-apheresis (Heparin-induced Extracorporeal Lipoprotein Precipitation system: a case report

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Rivasi Paolo

2009-12-01

Full Text Available Abstract Introduction Lipoprotein glomerulopathy is a glomerulonephritis which was described for the first time by Saito in 1989 and is currently acknowledged as a separate nosological entity. It is histologically characterized by a marked dilatation of the glomerular capillaries and the presence of lipoprotein thrombi in the glomerular lumens. The dyslipidemic profile is similar to that of type III dyslipoproteinemia with Apolipoprotein E values that are often high; proteinuria and renal dysfunction are present. Proteinuria often does not respond to steroid and cytostatic treatments. The phenotypic expression of lipoprotein glomerulopathy is most probably correlated to a genetic alteration of the lipoprotein metabolism (mutation of the Apolipoprotein E coding gene. In literature, lipoprotein glomerulopathies have mainly been reported in Japanese and Chinese subjects, except for three cases in the Caucasian race, reported in France and the USA. Case presentation We describe the case of a 60-year-old female, Caucasian patient suffering from lipoprotein glomerulopathy, carrier of a new mutation on the Apolipoprotein E gene (Apolipoprotein EMODENA, and treated successfully with low density lipoprotein-apheresis with the Heparin induced extracorporeal lipoprotein precipitation system. After a first phase of therapeutic protocol with statins, the patient was admitted for nephrotic syndrome, renal failure and hypertension. Since conventional treatment alone was not able to control dyslipidemia, aphaeretic treatment with heparin-induced Extracorporeal Lipoprotein Precipitation - apheresis (HELP-apheresis was started to maintain angiotensin converting enzyme inhibitor therapy for the treatment of hypertension. Treatment with HELP-apheresis led to a complete remission of the proteinuria in a very short time (four months, as well as control of hypercholesterolemia and renal function recovery. Conclusion According to this case of lipoprotein glomerulopathy

Profiling of oxidized phospholipids in lipoproteins from patients with coronary artery disease by hollow fiber flow field-flow fractionation and nanoflow liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Lee, Ju Yong; Byeon, Seul Kee; Moon, Myeong Hee

2015-01-20

Oxidized phospholipids (Ox-PLs) are oxidatively modified PLs that are produced during the oxidation of lipoproteins; oxidation of low density lipoproteins especially is known to be associated with the development of coronary artery disease (CAD). In this study, different lipoprotein classes (high density, low density, and very low density lipoproteins) from pooled plasma of CAD patients and pooled plasma from healthy controls were size-sorted on a semipreparative scale by multiplexed hollow fiber flow field-flow fractionation (MxHF5), and Ox-PLs that were extracted from each lipoprotein fraction were quantified by nanoflow liquid chromatography-tandem mass spectrometry (nLC-ESI-MS/MS). The present study showed that oxidation of lipoproteins occurred throughout all classes of lipoproteins with more Ox-PLs identified from CAD patient lipoproteins: molecular structures of 283 unique PL species (including 123 Ox-PLs) from controls and 315 (including 169 Ox-PLs) from patients were identified by data-dependent collision-induced dissociation experiments. It was shown that oxidation of PLs occurred primarily with hydroxylation of PL; in particular, a saturated acyl chain such as 16:0, 18:0, or even 18:1 at the sn-1 location of the glycerol backbone along with sn-2 acyl chains with at least two double bonds were identified. The acyl chain combinations commonly found for hydroxylated Ox-PLs in the lipoproteins of CAD patients were 16:0/18:2, 16:0/20:4, 18:0/18:2, and 18:0/20:4.

Caloric Restriction and Exercise Increase Plasma ANGPTL4 Levels in Humans via Elevated Free Fatty Acids

NARCIS (Netherlands)

Kersten, A.H.; Lichtenstein, L.L.; Steenbergen, E.; Mudde, C.M.; Hendriks, H.F.J.; Hesselink, M.K.; Schrauwen, P.; Müller, M.R.

2009-01-01

Objective - Plasma lipoprotein levels are determined by the balance between lipoprotein production and clearance. Recently, angiopoietin-like protein 4 (ANGPTL4) was uncovered as a novel endocrine factor that potently raises plasma triglyceride levels by inhibiting triglyceride clearance. However,

Caloric restriction and exercise increase plasma ANGPTL4 levels in humans via elevated free fatty acids.

NARCIS (Netherlands)

Kersten, S.; Lichtenstein, L.; Steenbergen, E.; Mudde, K.; Hendriks, H.F.; Hesselink, M.K.; Schrauwen, P.; Muller, M

2009-01-01

OBJECTIVE: Plasma lipoprotein levels are determined by the balance between lipoprotein production and clearance. Recently, angiopoietin-like protein 4 (ANGPTL4) was uncovered as a novel endocrine factor that potently raises plasma triglyceride levels by inhibiting triglyceride clearance. However,

Caloric restriction and exercise increase plasma ANGPTL4 levels in humans via elevated free fatty acids

NARCIS (Netherlands)

Kersten, S.; Lichtenstein, L.; Steenbergen, E.; Mudde, K.; Hendriks, H.F.J.; Hesselink, M.K.; Schrauwen, P.; Müller, M.

2009-01-01

OBJECTIVE-: Plasma lipoprotein levels are determined by the balance between lipoprotein production and clearance. Recently, angiopoietin-like protein 4 (ANGPTL4) was uncovered as a novel endocrine factor that potently raises plasma triglyceride levels by inhibiting triglyceride clearance. However,

Metabolism of triglyceride-rich lipoproteins and transfer of lipids to high-density lipoproteins (HDL) in vegan and omnivore subjects.

Science.gov (United States)

Vinagre, J C; Vinagre, C G; Pozzi, F S; Slywitch, E; Maranhão, R C

2013-01-01

Vegan diet excludes all foodstuffs of animal origin and leads to cholesterol lowering and possibly reduction of cardiovascular disease risk. The aim was to investigate whether vegan diet improves the metabolic pathway of triglyceride-rich lipoproteins, consisting in lipoprotein lipolysis and removal from circulation of the resulting remnants and to verify whether the diet alters HDL metabolism by changing lipid transfers to this lipoprotein. 21 vegan and 29 omnivores eutrophic and normolipidemic subjects were intravenously injected triglyceride-rich emulsions labeled with (14)C-cholesterol oleate and (3)H-triolein: fractional clearance rates (FCR, in min(-1)) were calculated from samples collected during 60 min for radioactive counting. Lipid transfer to HDL was assayed by incubating plasma samples with a donor nanoemulsion labeled with radioactive lipids; % lipids transferred to HDL were quantified in supernatant after chemical precipitation of non-HDL fractions and nanoemulsion. Serum LDL cholesterol was lower in vegans than in omnivores (2.1 ± 0.8, 2.7 ± 0.7 mmol/L, respectively, p vegans than in omnivores (0.016 ± 0.012, 0.003 ± 0.003, p vegans than in omnivores (2.7 ± 0.6, 3.5 ± 1.5%, p vegans, but the lipolysis process, estimated by triglyceride FCR was equal. Increased removal of atherogenic remnants and diminution of cholesteryl ester transfer may favor atherosclerosis prevention by vegan diet. Copyright © 2011 Elsevier B.V. All rights reserved.

ApoA-I/A-II-HDL positively associates with apoB-lipoproteins as a potential atherogenic indicator.

Science.gov (United States)

Kido, Toshimi; Kondo, Kazuo; Kurata, Hideaki; Fujiwara, Yoko; Urata, Takeyoshi; Itakura, Hiroshige; Yokoyama, Shinji

2017-11-29

We recently reported distinct nature of high-density lipoproteins (HDL) subgroup particles with apolipoprotein (apo) A-I but not apoA-II (LpAI) and HDL having both (LpAI:AII) based on the data from 314 Japanese. While plasma HDL level almost exclusively depends on concentration of LpAI having 3 to 4 apoA-I molecules, LpAI:AII appeared with almost constant concentration regardless of plasma HDL levels having stable structure with two apoA-I and one disulfide-dimeric apoA-II molecules (Sci. Rep. 6; 31,532, 2016). The aim of this study is further characterization of LpAI:AII with respect to its role in atherogenesis. Association of LpAI, LpAI:AII and other HDL parameters with apoB-lipoprotein parameters was analyzed among the cohort data above. ApoA-I in LpAI negatively correlated with the apoB-lipoprotein parameters such as apoB, triglyceride, nonHDL-cholesterol, and nonHDL-cholesterol + triglyceride, which are apparently reflected in the relations of the total HDL parameters to apoB-lipoproteins. In contrast, apoA-I in LpAI:AII and apoA-II positively correlated to the apoB-lipoprotein parameters even within their small range of variation. These relationships are independent of sex, but may slightly be influenced by the activity-related CETP mutations. The study suggested that LpAI:AII is an atherogenic indicator rather than antiatherogenic. These sub-fractions of HDL are to be evaluated separately for estimating atherogenic risk of the patients.

Combined analysis of six lipoprotein lipase genetic variants on triglycerides, high-density lipoprotein, and ischemic heart disease

DEFF Research Database (Denmark)

Wittrup, Hans H; Andersen, Rolf V; Tybjaerg-Hansen, Anne

2006-01-01

Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD).......Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD)....

Characterization of blood lipoproteins and validation of cholesterol and triacylglycerol assays for free-ranging polar bears (Ursus maritimus).

Science.gov (United States)

Whiteman, John P; Frank, Nicholas; Greller, Katie A; Harlow, Henry J; Ben-David, Merav

2013-05-01

Blood triacylglycerol (TG) and lipoproteins are important variables for evaluating nutritional status of wildlife, but measurements are often expensive and difficult. Performance of a small, portable blood analyzer intended for human medical diagnostics was evaluated in measuring these variables in plasma and serum from free-ranging polar bears (Ursus maritimus), which are experiencing nutritional stress related to sea ice loss. The analyzer accurately tracked changes in concentration of total cholesterol (Ctotal), cholesterol associated with high-density lipoprotein (CHDL), and TG during a validation protocol of diluting samples and spiking them with exogenous cholesterol and glycerol. Values of Ctotal and TG agreed well with values obtained by other methods (ultracentrifugation followed by colorimetric assays); agreement was variable for values of cholesterol associated with specific lipoproteins. Similar to a study of captive polar bears, ultracentrifugation methods revealed greater TG in very low-density lipoproteins than in low-density lipoprotein, which is unusual and merits additional study.

Identification of the Oxidized Low-Density Lipoprotein Scavenger Receptor CD36 in Plasma

DEFF Research Database (Denmark)

Handberg, Aase; Levin, Klaus; Højlund, Kurt

2006-01-01

BACKGROUND: Macrophage CD36 scavenges oxidized low-density lipoprotein, leading to foam cell formation, and appears to be a key proatherogenic molecule. Increased expression of CD36 has been attributed to hyperglycemia and to defective macrophage insulin signaling in insulin resistance. Premature...

Relations between lipoprotein(a) concentrations, LPA genetic variants, and the risk of mortality in patients with established coronary heart disease : a molecular and genetic association study

NARCIS (Netherlands)

Zewinger, Stephen; Kleber, Marcus E.; Tragante Do O, V; McCubrey, Raymond O.; Schmidt, Amand F.; Direk, Kenan; Laufs, Ulrich; Werner, Christian; Koenig, Wolfgang; Rothenbacher, Dietrich; Mons, Ute; Breitling, Lutz P; Brenner, Herrmann; Jennings, Richard T.; Petrakis, Ioannis; Triem, Sarah; Klug, Mira; Filips, Alexandra; Blankenberg, Stefan; Waldeyer, Christoph; Sinning, Christoph; Schnabel, Renate B.; Lackner, Karl J.; Vlachopoulou, Efthymia; Nygård, Ottar; Svingen, Gard Frodahl Tveitevåg; Pedersen, Eva Ringdal; Tell, Grethe S.; Sinisalo, Juha; Nieminen, Markku S.; Laaksonen, Reijo; Trompet, Stella; Smit, Roelof A.J.; Sattar, Naveed; Jukema, J. Wouter; Groesdonk, Heinrich V.; Delgado, Graciela; Stojakovic, Tatjana; Pilbrow, Anna P.; Cameron, Vicky A.; Richards, A. Mark; Doughty, Robert N.; Gong, Yan; Cooper-Dehoff, Rhonda M; Johnson, Julie A; Scholz, Markus; Beutner, Frank; Thiery, Joachim; Smith, J. Gustav; Vilmundarson, Ragnar O.; McPherson, Ruth; Stewart, Alexandre F. R.; Cresci, Sharon; Lenzini, Petra A.; Spertus, John A.; Olivieri, Oliviero; Girelli, Domenico; Martinelli, Nicola I.; Leiherer, Andreas; Saely, Christoph H.; Drexel, Heinz; Mündlein, Axel; Braund, Peter S; Nelson, Christopher P.; Samani, Nilesh J.; Kofink, Daniel; Hoefer, Imo E.; Pasterkamp, Gerard; Quyyumi, Arshed A.; Ko, Yi-An; Hartiala, Jaana A.; Allayee, Hooman; Tang, W. H. Wilson; Hazen, Stanley L.; Eriksson, Niclas; Held, Claes; Hagström, Emil; Wallentin, Lars; Åkerblom, Axel; Siegbahn, Agneta; Karp, Igor; Labos, Christopher; Pilote, Louise; Engert, James C.; Brophy, James M.; Thanassoulis, George; Bogaty, Peter; Szczeklik, Wojciech; Kaczor, Marcin; Sanak, Marek; Virani, Salim S.; Ballantyne, Christie M.; Lee, Vei Vei; Boerwinkle, Eric; Holmes, Michael V.; Horne, Benjamin D; Hingorani, Aroon D.; Asselbergs, Folkert W.; Patel, Riyaz S; Krämer, Bernhard K; Scharnagl, Hubert; Fliser, Danilo; März, Winfried; Speer, Thimoteus

Background Lipoprotein(a) concentrations in plasma are associated with cardiovascular risk in the general population. Whether lipoprotein(a) concentrations or LPA genetic variants predict long-term mortality in patients with established coronary heart disease remains less clear. Methods We obtained

Study of Plasma Electrolytic Oxidation Coatings on Aluminum Composites

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Leonid Agureev

2018-06-01

Full Text Available Coatings, with a thickness of up to 75 µm, were formed by plasma electrolytic oxidation (PEO under the alternating current electrical mode in a silicate-alkaline electrolyte on aluminum composites without additives and alloyed with copper (1–4.5%. The coatings’ structure was analyzed by scanning electron microscopy, X-ray microanalysis, X-ray photoelectron spectroscopy, nuclear backscattering spectrometry, and XRD analysis. The coatings formed for 60 min were characterized by excessive aluminum content and the presence of low-temperature modifications of alumina γ-Al2O3 and η-Al2O3. The coatings formed for 180 min additionally contained high-temperature corundum α-Al2O3, and aluminum inclusions were absent. The electrochemical behavior of coated composites and uncoated ones in 3% NaCl was studied. Alloyage of aluminum composites with copper increased the corrosion current density. Plasma electrolytic oxidation reduced it several times.

Lipoprotein lipase gene polymorphisms: associations with myocardial infarction and lipoprotein levels, the ECTIM study. Etude Cas Témoin sur l'Infarctus du Myocarde.

Science.gov (United States)

Jemaa, R; Fumeron, F; Poirier, O; Lecerf, L; Evans, A; Arveiler, D; Luc, G; Cambou, J P; Bard, J M; Fruchart, J C

1995-10-01

Several lipoprotein lipase (LPL) gene polymorphisms have been found associated with fasting lipid levels, but their impact on coronary heart disease (CHD) is less clearly established. We investigated associations of LPL polymorphisms (HindIII, PvuII, Ser447-->Ter) and the newly described mutation Asn291-->Ser with the risk of myocardial infarction (MI), severity of atherosclerosis, and fasting plasma lipoprotein concentrations in the ECTIM study (614 patients and 733 controls). The Ter447 allele had a lowering effect on triglycerides (P Ser polymorphisms did not exhibit any significant association with the biochemical traits examined. The HindIII genotype distributions differed between cases and controls, the odds ratios for MI associated with H+H+ and H+H- genotypes being 2.05 (P Ter and MI suggested that this mutation was unlikely to be the cause of the association found with HindIII. In some cases, the severity of atherosclerosis assessed by coronarography increased with the presence of P+ allele (coronary scores: 1.41, 1.57, and 1.64 in P-P-, P-P+, and P+P+ individuals respectively, P Ser mutation (1.58 vs. 1.90, P = 0.06). Our results suggest that the LPL gene is involved in the determination of lipoprotein profiles, the predisposition to CHD, and the severity of atherosclerosis.

Plasma apolipoprotein C-III levels, triglycerides, and coronary artery calcification in type 2 diabetics.

Science.gov (United States)

Qamar, Arman; Khetarpal, Sumeet A; Khera, Amit V; Qasim, Atif; Rader, Daniel J; Reilly, Muredach P

2015-08-01

Triglyceride-rich lipoproteins have emerged as causal risk factors for developing coronary heart disease independent of low-density lipoprotein cholesterol levels. Apolipoprotein C-III (ApoC-III) modulates triglyceride-rich lipoprotein metabolism through inhibition of lipoprotein lipase and hepatic uptake of triglyceride-rich lipoproteins. Mutations causing loss-of-function of ApoC-III lower triglycerides and reduce coronary heart disease risk, suggestive of a causal role for ApoC-III. Little data exist about the relationship of ApoC-III, triglycerides, and atherosclerosis in patients with type 2 diabetes mellitus (T2DM). Here, we examined the relationships between plasma ApoC-III, triglycerides, and coronary artery calcification in patients with T2DM. Plasma ApoC-III levels were measured in a cross-sectional study of 1422 subjects with T2DM but without clinically manifest coronary heart disease. ApoC-III levels were positively associated with total cholesterol (Spearman r=0.36), triglycerides (r=0.59), low-density lipoprotein cholesterol (r=0.16), fasting glucose (r=0.16), and glycosylated hemoglobin (r=0.12; Ptriglycerides (Tobit regression ratio, 1.43; 95% confidence interval, 0.94-2.18; P=0.086) and separately for very low-density lipoprotein cholesterol (Tobit regression ratio, 1.14; 95% confidence interval, 0.75-1.71; P=0.53). In persons with T2DM, increased plasma ApoC-III is associated with higher triglycerides, less favorable cardiometabolic phenotypes, and higher coronary artery calcification, a measure of subclinical atherosclerosis. Therapeutic inhibition of ApoC-III may thus be a novel strategy for reducing plasma triglyceride-rich lipoproteins and cardiovascular risk in T2DM. © 2015 American Heart Association, Inc.

Hepatic S1P deficiency lowers plasma cholesterol levels in apoB-containing lipoproteins when LDLR function is compromised.

Science.gov (United States)

Basu, Debapriya; Huq, Afroza; Iqbal, Jahangir; Hussain, M Mahmood; Jiang, Xian-Cheng; Jin, Weijun

2015-01-01

Site-1 protease (S1P) is the key enzyme required for activation of the sterol regulatory element binding proteins (SREBPs) that govern lipid synthesis. While S1P has been speculated to influence plasma apoB-containing lipoprotein (Blp) metabolism, there has been little investigative work. LDL receptor (LDLR) is the major receptor for clearing plasma LDL cholesterol (LDL-c). Proprotein convertase subtilisin kexin type 9 (PCSK9) modulates LDL-c through post-translational degradation of the LDLR. A hepatic-specific knockdown (KD) of S1P was achieved using floxed S1P mouse models (S1P(f/f) and LDLR(-/-)S1P(f/f)) and hepatic expression of Cre recombinase. Lipids were measured in total plasma and size fractionated plasma using colorimetric assays. Realtime polymerase chain reaction, western blotting and ELISA were used to determine hepatic expression of key genes/protein. Plasmid mediated overexpression and siRNA mediated knockdown of genes were performed in mouse primary hepatocytes to determine the mechanistic basis of PCSK9 gene regulation. A hepatic-specific KD of S1P resulted in a 45 % and 38 % reduction in plasma total cholesterol and triglyceride levels, respectively. Hepatic S1P KD had a minimal effect on plasma Blp cholesterol (Blp-c) in S1P(f/f) mice, despite significantly reducing VLDL secretion. Notably, hepatic S1P KD decreased the LDL receptor (LDLR) mRNA expression by 50 %. However, the reduction in LDLR protein levels was less than that of mRNA expression, especially under fed conditions. Further assessment of hepatic S1P deficiency revealed that it increased LDLR protein stability in vivo. Mechanistically, hepatic S1P KD was shown to decrease the liver and plasma levels of the protein proprotein convertase subtilisin/kexin type 9 (PCSK9), which degrades LDLR protein. This effect was more prominent in the fed condition and sufficient to account for the discordance in LDLR mRNA and protein levels. Furthermore, hepatic S1P was shown to regulate PCSK9

NMR-based lipidomic analysis of blood lipoproteins differentiates the progression of coronary heart disease.

Science.gov (United States)

Kostara, Christina E; Papathanasiou, Athanasios; Psychogios, Nikolaos; Cung, Manh Thong; Elisaf, Moses S; Goudevenos, John; Bairaktari, Eleni T

2014-05-02

Abnormal lipid composition and metabolism of plasma lipoproteins play a crucial role in the pathogenesis of coronary heart disease (CHD). A (1)H NMR-based lipidomic approach was used to investigate the correlation of coronary artery stenosis with the atherogenic (non-HDL) and atheroprotective (HDL) lipid profiles in 99 patients with CHD of various stages of disease and compared with 60 patients with normal coronary arteries (NCA), all documented in coronary angiography. The pattern recognition models created from lipid profiles predicted the presence of CHD with a sensitivity of 87% and a specificity of 88% in the HDL model and with 90% and 89% in the non-HDL model, respectively. Patients with mild, moderate, and severe coronary artery stenosis were progressively differentiated from those with NCA in the non-HDL model with a statistically significant separation of severe stage from both mild and moderate. In the HDL model, the progressive differentiation of the disease stages was statistically significant only between patients with mild and severe coronary artery stenosis. The lipid constituents of lipoproteins that mainly characterized the initial stages and then the progression of the disease were the high levels of saturated fatty acids in lipids in both HDL and non-HDL particles, the low levels of HDL-phosphatidylcholine, HDL-sphingomyelin, and omega-3 fatty acids and linoleic acid in lipids in non-HDL particles. The conventional lipid marker, total cholesterol, found in low levels in HDL and in high levels in non-HDL, also contributed to the onset of the disease but with a much lower coefficient of significance. (1)H NMR-based lipidomic analysis of atherogenic and atheroprotective lipoproteins could contribute to the early evaluation of the onset of coronary artery disease and possibly to the establishment of an appropriate therapeutic option.

Apolipoprotein E in umbilical cord blood plasma

International Nuclear Information System (INIS)

Forte, T.M.; Davis, P.A.; Blum, C.B.

1983-01-01

Adolipoprotein E (apo E), with a molecular weight of approximately 37,000 daltons, is a minor apolipoprotein constituent in adult plasma lipoproteins. This apolipoprotein, like apolipoprotein B, is a ligand recognized by specific lipoprotein receptor sites (B-E receptors) on cell surfaces. We have recently shown that a pronounced apo E band appears in umbilical cord blood low-density (LDL) lipoproteins and also in high density (HDL) lipoproteins. Densitometric scans of Coomassie blue G-250 stained polyacrylamide gels suggested that apo E was probably elevated in cord blood lipoproteins. To pursue this suggestion, apo E in cord blood was quantitated by radioimmunoassay and correlated with cord blood lipid levels. In addition, apo E levels in 20 normal adult volunteers were also examined

Atorvastatin decreases apolipoprotein C-III in apolipoprotein B-containing lipoprotein and HDL in type 2 diabetes: a potential mechanism to lower plasma triglycerides

NARCIS (Netherlands)

Dallinga-Thie, Geesje M.; Berk-Planken, Ingrid I. L.; Bootsma, Aart H.; Jansen, Hans

2004-01-01

Apolipoprotein (apo)C-III is a constituent of HDL (HDL apoC-III) and of apoB-containing lipoproteins (LpB:C-III). It slows the clearance of triglyceride-rich lipoproteins (TRLs) by inhibition of the activity of the enzyme lipoprotein lipase (LPL) and by interference with lipoprotein binding to

Phytosterols, Phytostanols, and Lipoprotein Metabolism

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Helena Gylling

2015-09-01

Full Text Available The efficacy of phytosterols and phytostanols added to foods and food supplements to obtain significant non-pharmacologic serum and low density lipoprotein (LDL cholesterol reduction is well documented. Irrespective of age, gender, ethnic background, body weight, background diet, or the cause of hypercholesterolemia and, even added to statin treatment, phytosterols and phytostanols at 2 g/day significantly lower LDL cholesterol concentration by 8%–10%. They do not affect the concentrations of high density lipoprotein cholesterol, lipoprotein (a or serum proprotein convertase subtilisin/kexin type 9. In some studies, phytosterols and phytostanols have modestly reduced serum triglyceride levels especially in subjects with slightly increased baseline concentrations. Phytosterols and phytostanols lower LDL cholesterol by displacing cholesterol from mixed micelles in the small intestine so that cholesterol absorption is partially inhibited. Cholesterol absorption and synthesis have been carefully evaluated during phytosterol and phytostanol supplementation. However, only a few lipoprotein kinetic studies have been performed, and they revealed that LDL apoprotein B-100 transport rate was reduced. LDL particle size was unchanged, but small dense LDL cholesterol concentration was reduced. In subjects with metabolic syndrome and moderate hypertriglyceridemia, phytostanols reduced not only non- high density lipoprotein (HDL cholesterol concentration but also serum triglycerides by 27%, and reduced the large and medium size very low density lipoprotein particle concentrations. In the few postprandial studies, the postprandial lipoproteins were reduced, but detailed studies with apoprotein B-48 are lacking. In conclusion, more kinetic studies are required to obtain a more complete understanding of the fasting and postprandial lipoprotein metabolism caused by phytosterols and phytostanols. It seems obvious, however, that the most atherogenic lipoprotein

Phytosterols, Phytostanols, and Lipoprotein Metabolism.

Science.gov (United States)

Gylling, Helena; Simonen, Piia

2015-09-17

The efficacy of phytosterols and phytostanols added to foods and food supplements to obtain significant non-pharmacologic serum and low density lipoprotein (LDL) cholesterol reduction is well documented. Irrespective of age, gender, ethnic background, body weight, background diet, or the cause of hypercholesterolemia and, even added to statin treatment, phytosterols and phytostanols at 2 g/day significantly lower LDL cholesterol concentration by 8%-10%. They do not affect the concentrations of high density lipoprotein cholesterol, lipoprotein (a) or serum proprotein convertase subtilisin/kexin type 9. In some studies, phytosterols and phytostanols have modestly reduced serum triglyceride levels especially in subjects with slightly increased baseline concentrations. Phytosterols and phytostanols lower LDL cholesterol by displacing cholesterol from mixed micelles in the small intestine so that cholesterol absorption is partially inhibited. Cholesterol absorption and synthesis have been carefully evaluated during phytosterol and phytostanol supplementation. However, only a few lipoprotein kinetic studies have been performed, and they revealed that LDL apoprotein B-100 transport rate was reduced. LDL particle size was unchanged, but small dense LDL cholesterol concentration was reduced. In subjects with metabolic syndrome and moderate hypertriglyceridemia, phytostanols reduced not only non- high density lipoprotein (HDL) cholesterol concentration but also serum triglycerides by 27%, and reduced the large and medium size very low density lipoprotein particle concentrations. In the few postprandial studies, the postprandial lipoproteins were reduced, but detailed studies with apoprotein B-48 are lacking. In conclusion, more kinetic studies are required to obtain a more complete understanding of the fasting and postprandial lipoprotein metabolism caused by phytosterols and phytostanols. It seems obvious, however, that the most atherogenic lipoprotein particles will be

Determination of composition and physical properties of partially ionized plasmas in the function of temperature

International Nuclear Information System (INIS)

Zaporowski, B.

1992-01-01

The investigations of various kinds of partially ionized plasma were conducted for the pressure of 0.1 MPa and in the range of temperature of 298.15 K to 24000 K. The physical properties of various kinds of partially ionized plasma depend mainly of their composition and temperature. The composition of particular kinds of partially ionized plasmas varies also in the function of temperature. Simultaneous going on of physical and chemical processes in plasma is the reason of difficulties in the calculations of plasma's physical properties. The use of the laws of macroscopic thermodynamics for the calculations of physical properties of partially ionized plasma is impossible. There are enough exact methods for measuring of physical properties of partially ionized plasma. For these reasons the theoretical method using the base of statistic physics was used to calculate the composition and physical properties of various kinds of partially ionized plasma. (author) 2 refs., 2 figs

The Application of a Modified d-ROMs Test for Measurement of Oxidative Stress and Oxidized High-Density Lipoprotein

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Fumiaki Ito

2017-02-01

Full Text Available Reactive oxygen species (ROS are involved in the initiation and progression of atherosclerosis. ROS-derived hydroperoxides, as an indicator of ROS production, have been measured by using the diacron reactive oxygen metabolites (d-ROMs test, which requires iron-containing transferrin in the reaction mixture. In this study we developed a modified d-ROMs test, termed the Fe-ROMs test, where iron ions were exogenously added to the reaction mixture. This modification is expected to exclude the assay variation that comes from different blood iron levels in individuals. In addition, this Fe-ROMs test was helpful for determining the class of plasma lipoproteins that are hydroperoxidized. Low-density lipoprotein/very low-density lipoprotein (LDL/VLDL and high-density lipoprotein (HDL were purified by use of an LDL/VLDL purification kit and the dextran sulfate-Mg2+ precipitation method, respectively; their hydroperoxide contents were assessed by performing the Fe-ROMs test. The majority of the hydroperoxides were detected only in the HDL fraction, not in the LDL/VLDL. Further detailed analysis of HDLs by size-exclusion high-performance liquid chromatography revealed that the hydroperoxide-containing molecules were small-sized HDLs. Because HDL was shown to be the principal vehicle for the plasma hydroperoxides, this Fe-ROMs test is a beneficial method for the assessment of oxidized-HDL levels. Indeed, Fe-ROMs levels were strongly associated with the levels of oxidized HDL, which were determined by performing the malondialdehyde-modified HDL enzyme immunoassay. In conclusion, the Fe-ROMs test using plasma itself or the HDL fraction after dextran sulfate-Mg2+ precipitation is useful to assess the functionality of HDL, because the oxidation of HDL impairs its antiatherogenic capacity.

Spirochetal Lipoproteins and Immune Evasion

Science.gov (United States)

Christodoulides, Alexei; Boyadjian, Ani; Kelesidis, Theodoros

2017-01-01

Spirochetes are a major threat to public health. However, the exact pathogenesis of spirochetal diseases remains unclear. Spirochetes express lipoproteins that often determine the cross talk between the host and spirochetes. Lipoproteins are pro-inflammatory, modulatory of immune responses, and enable the spirochetes to evade the immune system. In this article, we review the modulatory effects of spirochetal lipoproteins related to immune evasion. Understanding lipoprotein-induced immunomodulation will aid in elucidating innate pathogenesis processes and subsequent adaptive mechanisms potentially relevant to spirochetal disease vaccine development and treatment. PMID:28424696

Composition and plasma properties of the plasma sheet in the Earth's magnetotail

International Nuclear Information System (INIS)

Orsini, S.; Altwegg, K.; Balsiger, H.

1986-01-01

A statistical study of the plasma sheet properties, based on 300 h of data from the ISEE-1 Ion Composition Experiment, yiels a description of H + and He ++ densities and temperatures as functions of magnetospheric substorm activity and geocentric distance. The H + and He ++ temperatures are found to be well correlated, such that a ratio T(He ++ )/T(H + ) = 2.7±0.1 is typical. However, linear-regression analysis typically yields a nonvanishing T(He ++ ) in the limit T(H + ) #-> # 0, a limit that is approached through the addition of cold ionospheric H + to the plasma sheet during active periods. The plasma sheet proton temperature T(H + ) varies inversely with geocentric distance, and the radial gradient of T(H + ) increases with increasing activity index AE. The density ratio N (He ++ )/N(H + ) increases with geocentric distance, irrespective of AE

Radiolabelled lipoproteins and method for making same

International Nuclear Information System (INIS)

Lees, R.S.

1987-01-01

A method is described for detecting accumulation of low density lipoproteins in an arterial wall, the method comprising the steps of A. preparing a technetium-99m-labelled low density lipoprotein in a solution having a pH between 8 and 9; B. injecting the labelled low density lipoprotein into the vascular system of a patient; C. subsequently viewing the patient's vascular system with extracorporeally-located detecting means capable of detecting the labelled low density lipoprotein; D. determining from the detecting means the locations of the labelled density lipoproteins; and E. quantifying concentrations of the labelled low density lipoproteins at the locations to determine the accumulation of the lipoproteins

Increased hepatic cholesterol esterification with essential fatty acid deficiency (EFAD): relationship to plasma lipoprotein (LP) cholesterol content

International Nuclear Information System (INIS)

Ney, D.M.; Ziboh, V.A.; Schneeman, B.O.

1986-01-01

EFAD in the rat is associated with hepatic accumulation of esterified cholesterol and altered distribution of cholesterol between plasma and hepatic tissue. Little is known regarding the impact of EFAD on LP composition. To determine the relationship between hepatic cholesterol esterification and plasma lP composition in control (C) and EFAD male Wistar rats, the authors induced EFAD with continuous intragastric (IG) infusion of EFA-free solutions containing 3.5% of calories as triolein for 7 and 14 days. C animals received IG infusion of solutions containing 3.5% of calories as linoleic acid. Data in the EFAD groups reveal: (i) marked decreases in hepatic EFAs and increases in monoenoic acids; (ii) progressive increases in hepatic content of triglyceride and esterified cholesterol with 7 and 14 days of feeding; (iii) assay of acyl CoA:cholesterol acyltransferase activity in hepatic tissue using 14 C-cholesterol demonstrates an increase in hepatic cholesterol esterification when compared to C animals. Increased hepatic cholesterol esterification correlates with elevated levels of esterified cholesterol in plasma VLDL and HDL particles. These data indicate that the elevated levels of cholesterol esters in LP particles is due, at least in part, to increased hepatic cholesterol esterification with EFAD

Inhibition of triacylglycerol and apoprotein B secretion and of low density lipoprotein binding in Hep G2 cells by eicosapentaenoic acid

International Nuclear Information System (INIS)

Wong, S.H.; Nestel, P.J.

1987-01-01

The consumption of long chain polyunsaturated fatty acids of fish oils leads to profound lowering of plasma triacylglyercol (TAG) but not of plasma cholesterol. Reasons for this were investigated with the human hepatoma cell line, the Hep G2 cell. Incubations with oleic acid (OA), linoleic acid (LA) and the characteristic marine fatty acid eicosapentaenoic acid (EPA) enriched cellular TAG mass, though least with EPA. However, secretion of very low density lipoprotein (VLDL)-TAG and apoprotein B (apo B), measured from [ 3 H]-glycerol and [ 3 H]-leucine was markedly inhibited by EPA. Preincubation with LA reduced VLDL-TAG but not apo B secretion in comparison with OA which stimulated both. A possible effect on low density lipoprotein (LDL) removal was studied by measuring [ 125 I]-LDL binding. Preincubation with either EPA or LA inhibited the saturable binding of LDL, observed with OA and control incubations. The binding of lipoproteins containing chylomicron remnants was not affected by any of the fatty acids

Graphene-induced strengthening in spark plasma sintered tantalum carbide–nanotube composite

International Nuclear Information System (INIS)

Lahiri, Debrupa; Khaleghi, Evan; Bakshi, Srinivasa Rao; Li, Wei; Olevsky, Eugene A.; Agarwal, Arvind

2013-01-01

Transverse rupture strength of spark plasma sintered tantalum carbide (TaC) composites reinforced with long and short carbon nanotubes (CNTs) is reported. The rupture strength depends on the transformation behavior of the CNTs during spark plasma sintering, which is dependent on their length. The TaC composite with short nanotubes shows the highest specific rupture strength. Shorter CNTs transform into multi-layered graphene sheets between TaC grains, whereas long ones retain the tubular structure. Two-dimensionsal graphene platelets offer higher resistance to pull-out, resulting in delayed fracture and higher strength.

Cultured human astrocytes secrete large cholesteryl ester- andtriglyceride-rich lipoproteins along with endothelial lipase

Energy Technology Data Exchange (ETDEWEB)

Yang, Lin; Liu, Yanzhu; Forte, Trudy M.; Chisholm, Jeffrey W.; Parks, John S.; Shachter, Neil S.

2003-12-01

We cultured normal human astrocytes and characterized their secreted lipoproteins. Human astrocytes secreted lipoproteins in the size range of plasma VLDL (Peak 1), LDL (Peak 2), HDL (Peak 3) and a smaller peak (Peak 4), as determined by gel filtration chromatography, nondenaturing gradient gel electrophoresis and transmission electron microscopy. Cholesterol enrichment of astrocytes led to a particular increase in Peak 1. Almost all Peak 2, 3 and 4 cholesterol and most Peak 1 cholesterol was esterified (unlike mouse astrocyte lipoproteins, which exhibited similar peaks but where cholesterol was predominantly non-esterified). Triglycerides were present at about 2/3 the level of cholesterol. LCAT was detected along with two of its activators, apolipoprotein (apo) A-IV and apoC-I. ApoA-I and apoA-II mRNA and protein were absent. ApoJ was present equally in all peaks but apoE was present predominantly in peaks 3 and 4. ApoB was not detected. The electron microscopic appearance of Peak 1 lipoproteins suggested partial lipolysis leading to the detection of a heparin-releasable triglyceride lipase consistent with endothelial lipase. The increased neuronal delivery of lipids from large lipoprotein particles, for which apoE4 has greater affinity than does apoE3, may be a mechanism whereby the apoE {var_epsilon}4 allele contributes to neurodegenerative risk.

Plasma lipoprotein(a levels: a comparison between diabetic and non-diabetic patients with acute ischemic stroke

Directory of Open Access Journals (Sweden)

Holanda Maurus Marques de Almeida

2004-01-01

Full Text Available OBJECTIVE: The aim of this study was to evaluate lipoprotein(a (Lp(a, total cholesterol, high density lipoprotein cholesterol (HDL, low density lipoprotein cholesterol (LDL, very low density lipoprotein cholesterol (VLDL , triglycerides , apolipoprotein A (apo A and B100 (apo B100, uric acid, glycaemic and insulin plasmatic concentrations in patients affected by acute stroke. In this group of patients, we have compared the variables between type 2 diabetic patients and non-diabetic patients. METHOD: We evaluate a total of 34 non-diabetic patients (22 males and 12 females; mean age 66.71 ± 10.83 years and a group of 26 type 2 diabetic patients (15 males and 11 females; mean age 66.35 ± 9.92 years in a cross-sectional study. RESULTS: Mean Lp(a concentration did not significantly differ between type 2 diabetic patients and non-diabetic subjects (29.49 ± 23.09 vs 44.81 ± 44.34 mg/dl. The distribution of Lp(alevels was highly skewed towards the higher levels in both groups, being over 30 mg/dl in 50%. Lp(a concentration was positively correlated with abdominal adiposity, using waist-hip ratio(WHR(p< 0.05. No association was found between Lp(a and others risk factors like sex, age, other lipidic parameters and the presence of stroke. CONCLUSIONS: Our results showed that there were no significant differences between diabetic and non-diabetic patients' serum Lp(a levels, which indicates that elevated Lp(a levels were associated with ischemic stroke, irrespective of the presence of type 2 diabetes mellitus (type 2 DM.

Features of film growth during plasma anodizing of Al 2024/SiC metal matrix composite

Energy Technology Data Exchange (ETDEWEB)

Xue Wenbin [Key Laboratory for Radiation Beam Technology and Materials Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China)]. E-mail: xuewb@bnu.edu.cn

2006-07-15

Plasma anodizing is a novel promising process to fabricate corrosion-resistant protective films on metal matrix composites. The corrosion-resistant films were prepared by plasma anodizing on SiC reinforced aluminum matrix composite. The morphology and microstructure of films were analyzed by scanning electron microscopy. Specifically, the morphology of residual SiC reinforcement particles in the film was observed. It is found that the most SiC reinforcement particles have been molten to become silicon oxide, but a few tiny SiC particles still remain in the film close to the composite/film interface. This interface is irregular due to the hindering effect of SiC particles on the film growth. Morphology and distribution of residual SiC particles in film provide direct evidence to identify the local melt occurs in the interior of plasma anodizing film even near the composite/film interface. A model of film growth by plasma anodizing on metal matrix composites was proposed.

Features of film growth during plasma anodizing of Al 2024/SiC metal matrix composite

International Nuclear Information System (INIS)

Xue Wenbin

2006-01-01

Plasma anodizing is a novel promising process to fabricate corrosion-resistant protective films on metal matrix composites. The corrosion-resistant films were prepared by plasma anodizing on SiC reinforced aluminum matrix composite. The morphology and microstructure of films were analyzed by scanning electron microscopy. Specifically, the morphology of residual SiC reinforcement particles in the film was observed. It is found that the most SiC reinforcement particles have been molten to become silicon oxide, but a few tiny SiC particles still remain in the film close to the composite/film interface. This interface is irregular due to the hindering effect of SiC particles on the film growth. Morphology and distribution of residual SiC particles in film provide direct evidence to identify the local melt occurs in the interior of plasma anodizing film even near the composite/film interface. A model of film growth by plasma anodizing on metal matrix composites was proposed

Plasma cholesterol and related lipid levels of seemingly healthy ...

African Journals Online (AJOL)

The purpose of this study was achieved through analysis of fasting plasma samples for the following: Total cholesterol (TC), Triacylglycerols (TG), High density lipoprotein cholesterol (HDL), Low density lipoprotein cholesterol (LDL), and molar ratios of LDL/HDL, TC/ HDL, and TC/TG. Methods: One hundred and seventy four ...

Structure and characteristics of functional powder composite materials obtained by spark plasma sintering

Science.gov (United States)

Oglezneva, S. A.; Kachenyuk, M. N.; Kulmeteva, V. B.; Ogleznev, N. B.

2017-07-01

The article describes the results of spark plasma sintering of ceramic materials based on titanium carbide, titanium carbosilicide, ceramic composite materials based on zirconium oxide, strengthened by carbon nanostructures and composite materials of electrotechnical purpose based on copper with addition of carbon structures and titanium carbosilicide. The research shows that the spark plasma sintering can achieve relative density of the material up to 98%. The effect of sintering temperature on the phase composition, density and porosity of the final product has been studied. It was found that with addition of carbon nanostructures the relative density and hardness decrease, but the fracture strength of ZrO2 increases up to times 2. The relative erosion resistance of the electrodes made of composite copper-based powder materials, obtained by spark plasma sintering during electroerosion treatment of tool steel exceeds that parameter of pure copper up to times 15.

Metabolic alterations, HFE gene mutations and atherogenic lipoprotein modifications in patients with primary iron overload.

Science.gov (United States)

Meroño, Tomás; Brites, Fernando; Dauteuille, Carolane; Lhomme, Marie; Menafra, Martín; Arteaga, Alejandra; Castro, Marcelo; Saez, María Soledad; Ballerga, Esteban González; Sorroche, Patricia; Rey, Jorge; Lesnik, Philippe; Sordá, Juan Andrés; Chapman, M John; Kontush, Anatol; Daruich, Jorge

2015-05-01

Iron overload (IO) has been associated with glucose metabolism alterations and increased risk of cardiovascular disease (CVD). Primary IO is associated with mutations in the HFE gene. To which extent HFE gene mutations and metabolic alterations contribute to the presence of atherogenic lipoprotein modifications in primary IO remains undetermined. The present study aimed to assess small, dense low-density lipoprotein (LDL) levels, chemical composition of LDL and high-density lipoprotein (HDL) particles, and HDL functionality in IO patients. Eighteen male patients with primary IO and 16 sex- and age-matched controls were recruited. HFE mutations (C282Y, H63D and S65C), measures of insulin sensitivity and secretion (calculated from the oral glucose tolerance test), chemical composition and distribution profile of LDL and HDL subfractions (isolated by gradient density ultracentrifugation) and HDL functionality (as cholesterol efflux and antioxidative activity) were studied. IO patients compared with controls exhibited insulin resistance (HOMA-IR (homoeostasis model assessment-estimated insulin resistance): +93%, PHFE genotypes. C282Y homozygotes (n=7) presented a reduced β-cell function and insulin secretion compared with non-C282Y patients (n=11) (-58% and -73%, respectively, PHFE gene mutations are involved in the presence of atherogenic lipoprotein modifications in primary IO. To what extent such alterations could account for an increase in CVD risk remains to be determined.

Familial lipoprotein lipase deficiency

Science.gov (United States)

... lack an enzyme called lipoprotein lipase. Without this enzyme, the body cannot break down fat from digested food. Fat particles called chylomicrons build up in the blood. Risk factors include a family history of lipoprotein lipase deficiency. The condition is usually ...

Synthesis and characterization of aluminium–alumina micro- and nano-composites by spark plasma sintering

International Nuclear Information System (INIS)

Dash, K.; Chaira, D.; Ray, B.C.

2013-01-01

Graphical abstract: The evolution of microstructure by varying the particle size of reinforcement in the matrix employing spark plasma sintering has been demonstrated here in Al–Al 2 O 3 system. An emphasis has been laid on varying the reinforcement particle size and evaluating the microstructural morphologies and their implications on mechanical performance of the composites. Nanocomposites of 0.5, 1, 3, 5, 7 volume % alumina (average size 2 O 3 micro- and nano-composites fabricated by spark plasma sintering. • Better matrix-reinforcement integrity in nanocomposites than microcomposites. • Spark plasma sintering method results in higher density and hardness values. • High density and hardness values of nanocomposites than microcomposites. • High dislocation density in spark plasma sintered Al–Al 2 O 3 composites. - Abstract: In the present study, an emphasis has been laid on evaluation of the microstructural morphologies and their implications on mechanical performance of the composites by varying the reinforcement particle size. Nanocomposites of 0.5, 1, 3, 5, 7 volume % alumina (average size 2 O 3 nancomposites respectively. Spark plasma sintering imparts enhanced densification and matrix-reinforcement proximity which have been corroborated with the experimental results

Examination of the relation between periodontal health status and cardiovascular risk factors: serum total and high density lipoprotein cholesterol, C-reactive protein, and plasma fibrinogen.

Science.gov (United States)

Wu, T; Trevisan, M; Genco, R J; Falkner, K L; Dorn, J P; Sempos, C T

2000-02-01

Using data from the Third National Health and Nutrition Examination Survey (1988-1994), the authors examined the relation between periodontal health and cardiovascular risk factors: serum total and high density lipoprotein cholesterol, C-reactive protein, and plasma fibrinogen. A total of 10,146 participants were included in the analyses of cholesterol and C-reactive protein and 4,461 in the analyses of fibrinogen. Periodontal health indicators included the gingival bleeding index, calculus index, and periodontal disease status (defined by pocket depth and attachment loss). While cholesterol and fibrinogen were analyzed as continuous variables, C-reactive protein was dichotomized into two levels. The results show a significant relation between indicators of poor periodontal status and increased C-reactive protein and fibrinogen. The association between periodontal status and total cholesterol level is much weaker. No consistent association between periodontal status and high density lipoprotein cholesterol was detectable. Similar patterns of association were observed for participants aged 17-54 years and those 55 years and older. In conclusion, this study suggests that total cholesterol, C-reactive protein, and fibrinogen are possible intermediate factors that may link periodontal disease to elevated cardiovascular risk.

Receptor-mediated endocytosis of low density lipoproteins in aortic endothelial cells

International Nuclear Information System (INIS)

Sanan, D.A.

1986-04-01

Lipoprotein binding and metabolism in actively-dividing (subconfluent) and quiescent (postconfluent) bovine aortic endothelial cells (ECs) were qualitatively investigated by fluorescence microscopy using dioctadecylindocarbocyanine-labelled lipoproteins and by indirect immunofluorescence microscopy. LDL and acetylated-LDL (AcLDL) were seen bound to the surfaces of subconfluent ECs (at 4 degrees C or at 37 degrees C), as a random distribution of punctate foci. ECs therefore closely resembled fibroblasts in the distribution of LDL receptors on their surfaces. No binding of LDL was seen on postconfluent EC surfaces by either direct or indirect fluorescence microscopy. The patterns of AcLDL binding on postconfluent ECs resembled those on subconfluent ECs. Intracellular LDL and AcLDL occurred as perinuclear accumulations of large fluorescent disc-shaped profiles in subconfluent ECs. These accumulations were shown to arise from surface-bound material by pulse-chase experiments. Intracellular LDL was absent in the majority of postconfluent ECs, while AcLDL accumulation was massive. 'Wounding' of cultures allowed simultaneous assessment of lipoprotein metabolism in quiescent and actively-dividing areas of the same culture. It is concluded that postconfluent quiescent bovine aortic ECs in vitro metabolise virtually no LDL via the LDL-receptor pathway due to a vanishingly low number of LDL receptors. This contrasts with the ability of postconfluent cells to metabolise relatively large amounts of AcLDL via a receptor-mediated mechanism. The significance of these conclusions is discussed with respect to the interaction of plasma lipoproteins with the endothelium in vivo. 301 refs

A solid dietary fat containing fish oil redistributes lipoprotein subclasses without increasing oxidative stress in men

DEFF Research Database (Denmark)

Tholstrup, T.; Hellgren, Lars; Petersen, M.

2004-01-01

, a solid dietary fat containing (n-3) PUFA decreased plasma TAG, VLDL, and IDL cholesterol, and redistributed lipoprotein subclasses in LDL and HDL, with a higher concentration of the larger and less atherogenic subfractions. These changes took place without an increase in oxidative stress as measured...... of F than O fat (P oxidation measured as the ratio of plasma isoprostanes F-2 to arachidonic acid and urinary isoprostanes, whereas the vitamin E activity/plasma total lipids ratio was higher after intake of F than O (P = 0.008). In conclusion...

Plasma lipid profile of Wistar albino rats fed palm oil-supplemented ...

African Journals Online (AJOL)

The plasma levels of Total cholesterol (TC), Triglycerides (TG), Low-density lipoprotein (LDL), and High-density lipoprotein (HDL) were determined at 4-, 8-, and ... The TC/HDL ratio increased non-significantly from 3.12+0.29 to 3.55+0.29.

Geotail observations of plasma sheet ion composition over 16 years: On variations of average plasma ion mass and O+ triggering substorm model

Science.gov (United States)

Nosé, M.; Ieda, A.; Christon, S. P.

2009-07-01

We examined long-term variations of ion composition in the plasma sheet, using energetic (9.4-212.1 keV/e) ion flux data obtained by the suprathermal ion composition spectrometer (STICS) sensor of the energetic particle and ion composition (EPIC) instrument on board the Geotail spacecraft. EPIC/STICS observations are available from 17 October 1992 for more than 16 years, covering the declining phase of solar cycle 22, all of solar cycle 23, and the early phase of solar cycle 24. This unprecedented long-term data set revealed that (1) the He+/H+ and O+/H+ flux ratios in the plasma sheet were dependent on the F10.7 index; (2) the F10.7 index dependence is stronger for O+/H+ than He+/H+; (3) the O+/H+ flux ratio is also weakly correlated with the ΣKp index; and (4) the He2+/H+ flux ratio in the plasma sheet appeared to show no long-term trend. From these results, we derived empirical equations related to plasma sheet ion composition and the F10.7 index and estimated that the average plasma ion mass changes from ˜1.1 amu during solar minimum to ˜2.8 amu during solar maximum. In such a case, the Alfvén velocity during solar maximum decreases to ˜60% of the solar minimum value. Thus, physical processes in the plasma sheet are considered to be much different between solar minimum and solar maximum. We also compared long-term variation of the plasma sheet ion composition with that of the substorm occurrence rate, which is evaluated by the number of Pi2 pulsations. No correlation or negative correlation was found between them. This result contradicts the O+ triggering substorm model, in which heavy ions in the plasma sheet increase the growth rate of the linear ion tearing mode and play an important role in localization and initiation of substorms. In contrast, O+ ions in the plasma sheet may prevent occurrence of substorms.

Synthetic Lipoproteins as Carriers for Drug Delivery.

Science.gov (United States)

Huang, Gangliang; Liu, Yang; Huang, Hualiang

2016-01-01

Synthetic lipoprotein is an effective carrier of targeted delivery for drugs. It has the very small size, good biocompatibility, suitable half-life, and specific lipoprotein receptorbinding capacity. Compared with the traditional natural lipoprotein, synthetic lipoprotein not only retains the original biological characteristics and functions, but also exhibits the excellent characteristics in drug delivery. Herein, the advantages, development, applications, and prospect of synthetic lipoproteins as drug carriers were summarized.

Zeolite Nanoparticles for Selective Sorption of Plasma Proteins.

Science.gov (United States)

Rahimi, M; Ng, E-P; Bakhtiari, K; Vinciguerra, M; Ali Ahmad, H; Awala, H; Mintova, S; Daghighi, M; Bakhshandeh Rostami, F; de Vries, M; Motazacker, M M; Peppelenbosch, M P; Mahmoudi, M; Rezaee, F

2015-11-30

The affinity of zeolite nanoparticles (diameter of 8-12 nm) possessing high surface area and high pore volume towards human plasma proteins has been investigated. The protein composition (corona) of zeolite nanoparticles has been shown to be more dependent on the plasma protein concentrations and the type of zeolites than zeolite nanoparticles concentration. The number of proteins present in the corona of zeolite nanoparticles at 100% plasma (in vivo state) is less than with 10% plasma exposure. This could be due to a competition between the proteins to occupy the corona of the zeolite nanoparticles. Moreover, a high selective adsorption for apolipoprotein C-III (APOC-III) and fibrinogen on the zeolite nanoparticles at high plasma concentration (100%) was observed. While the zeolite nanoparticles exposed to low plasma concentration (10%) exhibited a high selective adsorption for immunoglobulin gamma (i.e. IGHG1, IGHG2 and IGHG4) proteins. The zeolite nanoparticles can potentially be used for selectively capture of APOC-III in order to reduce the activation of lipoprotein lipase inhibition during hypertriglyceridemia treatment. The zeolite nanoparticles can be adapted to hemophilic patients (hemophilia A (F-VIII deficient) and hemophilia B (F-IX deficient)) with a risk of bleeding, and thus might be potentially used in combination with the existing therapy.

Remnant lipoproteins.

Science.gov (United States)

Varbo, Anette; Nordestgaard, Børge G

2017-08-01

To review recent advances in the field of remnant lipoproteins and remnant cholesterol with a focus on cardiovascular disease risk. In line with previous years' research, current observational, genetic, and mechanistic studies find remnant lipoproteins (defined in different ways) to be involved in atherosclerosis development and cardiovascular disease risk. High concentrations of remnant cholesterol could explain some of the residual risk of cardiovascular disease seen after LDL cholesterol lowering. This will be increasingly important as populations worldwide become more obese and more have diabetes, both of which elevate remnant cholesterol concentrations. Many smaller scale studies and post hoc analyses show that remnant cholesterol can be lowered by different types of drugs; however, results from large scale studies with the primary aim of reducing cardiovascular disease risk through lowering of remnant cholesterol in individuals with elevated concentrations are still missing, although some are under way. Remnant cholesterol is a risk factor for cardiovascular disease, and can be lowered by different types of drugs; however, large scale studies of cardiovascular disease risk reduction through remnant lipoprotein lowering are under way.

Microwave plasma CVD of NANO structured tin/carbon composites

Science.gov (United States)

Marcinek, Marek [Warszawa, PL; Kostecki, Robert [Lafayette, CA

2012-07-17

A method for forming a graphitic tin-carbon composite at low temperatures is described. The method involves using microwave radiation to produce a neutral gas plasma in a reactor cell. At least one organo tin precursor material in the reactor cell forms a tin-carbon film on a supporting substrate disposed in the cell under influence of the plasma. The three dimensional carbon matrix material with embedded tin nanoparticles can be used as an electrode in lithium-ion batteries.

Genetics of non-conventional lipoprotein fractions

Science.gov (United States)

Lipoprotein subclass measures associate with cardiometabolic disease risk. Currently the information that lipoproteins convey on disease risk over that of traditional demographic and lipid measures is minimal, and so their use is clinics is limited. However, lipoprotein subclass perturbations repres...

W/Cu composites produced by low temperature Pulse Plasma Sintering

International Nuclear Information System (INIS)

Rosinski, M.S.; Fortuna, E.; Michalski, A.J.; Kurzydlowski, K.J.

2006-01-01

The plasma facing components (PFCs) must withstand the thermal, mechanical and neutron loads under cyclic mode of operation and vacuum. Despite that PFCs of ITER and demonstration reactors must assure reliability and long in service lifetime. For that reason PFCs are designed to be made of beryllium, tungsten or carbon fibre composites armours and copper based heat sink material. Such design concepts can only be used if joining methods of these dissimilar materials are resolved. Several techniques have been developed for joining W and Cu e. g. casting of pure Cu onto W, high temperature brazing, direct diffusion bonding or CVDs of W onto Cu. The main problem in the development of such joints is the large difference in the coefficients of thermal expansion, CTE (alpha Cu > 4 alpha W) and elastic modula (ECu > 0.2 EW). These differences result in large stresses at the W/Cu interfaces during manufacturing and/or during operation, which may lead to cracking or delamination reducing lifetime of the components. Possible solution to this problem is the use of W-Cu composites (FGM). W-Cu composites are widely used for spark erosion electrodes, in heavy duty circuit breakers and as heat sinks of microelectronic devices. They are commonly produced by infiltration of a porous sintered tungsten by liquid copper. Other technological route is powder metallurgy. Coatings can be produced by low pressure plasma spraying. All these methods, however, are known to have some disadvantages. For infiltration there is a 30 wt.% limit of Cu content while for powder metallurgy and plasma spraying techniques porosity is of concern. In our work the W-Cu composites of different composition were produced by pulse plasma sintering (PPS). This new method utilizes pulsed high electric discharges to heat the powders under uniaxial load. The arc discharges clean surface of powder particles and intensify diffusion. The total sintering time is reduced to several minutes. In our investigations various

Serum Sialic Acid Concentration and Content in ApoB-Containing Lipoproteins in Liver Diseases.

Science.gov (United States)

Gudowska, Monika; Gruszewska, Ewa; Cylwik, Bogdan; Panasiuk, Anatol; Filisiak, Robert; Szmitkowski, Maciej; Chrostek, Lech

2016-01-01

The great significance for the metabolism of lipoproteins is the composition of carbohydrate chain of apolipoproteins, where sialic acid (SA) is located. In VILDL and LDL sialic acid is attached to apolipoprotein B. The sialylation of serum proteins including apolipoprotein B can be affected in the course of liver diseases. Therefore, the aim of this study was to assess the effect of liver diseases on the concentration and content of SA in ApoB-containing lipoproteins. The tested group consisted of 165 patients (118 males, 47 females) with liver diseases: alcoholic cirrhosis, non-alcoholic cirrhosis, chronic hepatitis, toxic hepatitis, chronic viral hepatitis, and liver cancer. ApoB-containing lipoproteins were isolated by a turbidimetric procedure and SA concentration was measured according to an enzymatic method. There was a significant increase in the serum concentration of SA in ApoB-containing lipoproteins in viral hepatitis. Although the serum concentration of ApoB was not significantly different between specific liver diseases, the serum levels of SA in ApoB-containing lipoproteins appeared to be different. There is an association between SA concentration and triglycerides in alcoholic cirrhosis and viral hepatitis. Also, in viral hepatitis SA concentration correlated negatively with HDL-cholesterol. The content of SA in ApoB-containing lipoproteins in alcoholic cirrhosis and viral hepatitis was significantly higher than that in the control group, but did not differ between diseases. This study may explain the variations in serum lipids and lipoproteins in liver diseases. It seems that the reason for these abnormalities is the changes in the concentration of sialic acid in ApoB-containing lipoproteins.

Revisiting the gram-negative lipoprotein paradigm

Science.gov (United States)

The processing of lipoproteins (lpps) in Gram-negative bacteria is generally considered to be an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein n-acyltransferase. The mature lipoproteins are then sorted...

Involvement of microtubules in lipoprotein degradation and utilization for steroidogenesis in cultured rat luteal cells

International Nuclear Information System (INIS)

Rajan, V.P.; Menon, K.M.

1985-01-01

Cells isolated from superovulated rat ovaries metabolize low density lipoprotein (LDL) and high density lipoprotein (HDL) of human or rat origin and use the lipoprotein-derived cholesterol as a precursor for progesterone production. Under in vitro conditions, both lipoproteins are internalized and degraded in the lysosomes, although degradation of HDL is of lower magnitude than that of LDL. In this report we have examined the role of cellular microtubules in the internalization and degradation of human LDL and HDL in cultured rat luteal cells. The microtubule depolymerizing agents colchicine, podophyllotoxin, vinblastine, and nocodazole as well as taxol, deuterium oxide, and dimethyl sulfoxide, which are known to rapidly polymerize cellular tubulin into microtubules, were used to block the function of microtubules. When these antimicrotubule agents were included in the incubations, degradation of the apolipoproteins of [ 125 I]iodo-LDL and [ 125 I]iodo-HDL by the luteal cells was inhibited by 50-85% compared to untreated control values. Maximum inhibitory effects were observed when the cells were preincubated with the inhibitor for at least 4 h at 37 C before treatment with the labeled lipoprotein. Lipoprotein-stimulated progesterone production by luteal cells was also inhibited by 50% or more in the presence of antimicrotubule agents. However, basal and hCG-stimulated progesterone production were unaffected by these inhibitors. The binding of [ 125 I]iodo-LDL and [ 125 I]iodo-HDL to luteal cell plasma membrane receptors was not affected by the microtubule inhibitors. Although binding was unaffected and degradation was impaired in the presence of the inhibitors, there was no detectable accumulation of undegraded lipoprotein within the cells during the 24 h of study

Classifying lipoproteins based on their polar profiles.

Science.gov (United States)

Polanco, Carlos; Castañón-González, Jorge Alberto; Buhse, Thomas; Uversky, Vladimir N; Amkie, Rafael Zonana

2016-01-01

The lipoproteins are an important group of cargo proteins known for their unique capability to transport lipids. By applying the Polarity index algorithm, which has a metric that only considers the polar profile of the linear sequences of the lipoprotein group, we obtained an analytical and structural differentiation of all the lipoproteins found in UniProt Database. Also, the functional groups of lipoproteins, and particularly of the set of lipoproteins relevant to atherosclerosis, were analyzed with the same method to reveal their structural preference, and the results of Polarity index analysis were verified by an alternate test, the Cumulative Distribution Function algorithm, applied to the same groups of lipoproteins.

Endothelial Dysfunction in Children With Obstructive Sleep Apnea Is Associated With Elevated Lipoprotein-Associated Phospholipase A2 Plasma Activity Levels.

Science.gov (United States)

Kheirandish-Gozal, Leila; Philby, Mona F; Qiao, Zhuanghong; Khalyfa, Abdelnaby; Gozal, David

2017-02-09

Obstructive sleep apnea (OSA) is a highly prevalent condition, especially in obese children, and has been associated with increased risk for endothelial dysfunction and dislipidemia, which are precursors of atherosclerosis. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is recognized as an independent risk factor for cardiovascular risk and atheromatous plaque activity. We hypothesized that Lp-PLA2 levels would be elevated in children with OSA, particularly among obese children who also manifest evidence of endothelial dysfunction. One hundred sixty children (mean age 7.1±2.3 years), either nonobese with (n=40) and without OSA (n=40) or obese with (n=40) and without OSA (n=40) underwent overnight polysomnographic and postocclusive reperfusion evaluation and a fasting blood draw the morning after the sleep study. In addition to lipid profile, Lp-PLA2 plasma activity was assessed using a commercial kit. Obese children and OSA children had significantly elevated plasma Lp-PLA2 activity levels compared to controls. Furthermore, when both obesity and OSA were concurrently present or when endothelial function was present, Lp-PLA2 activity was higher. Treatment of OSA by adenotonsillectomy resulted in reductions of Lp-PLA2 activity (n=37; P <0.001). Lp-PLA2 plasma activity is increased in pediatric OSA and obesity, particularly when endothelial dysfunction is present, and exhibits decreases on OSA treatment. The short-term and long-term significance of these findings in relation to cardiovascular risk remain undefined. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Hepatic trans-Golgi action coordinated by the GTPase ARFRP1 is crucial for lipoprotein lipidation and assembly[S

Science.gov (United States)

Hesse, Deike; Radloff, Katrin; Jaschke, Alexander; Lagerpusch, Merit; Chung, Bomee; Tailleux, Anne; Staels, Bart; Schürmann, Annette

2014-01-01

The liver is a major organ in whole body lipid metabolism and malfunctioning can lead to various diseases including dyslipidemia, fatty liver disease, and type 2 diabetes. Triglycerides and cholesteryl esters are packed in the liver as very low density lipoproteins (VLDLs). Generation of these lipoproteins is initiated in the endoplasmic reticulum and further maturation likely occurs in the Golgi. ADP-ribosylation factor-related protein 1 (ARFRP1) is a small trans-Golgi-associated guanosine triphosphatase (GTPase) that regulates protein sorting and is required for chylomicron lipidation and assembly in the intestine. Here we show that the hepatocyte-specific deletion of Arfrp1 (Arfrp1liv−/−) results in impaired VLDL lipidation leading to reduced plasma triglyceride levels in the fasted state as well as after inhibition of lipoprotein lipase activity by Triton WR-1339. In addition, the concentration of ApoC3 that comprises 40% of protein mass of secreted VLDLs is markedly reduced in the plasma of Arfrp1liv−/− mice but accumulates in the liver accompanied by elevated triglycerides. Fractionation of Arfrp1liv−/− liver homogenates reveals more ApoB48 and a lower concentration of triglycerides in the Golgi compartments than in the corresponding fractions from control livers. In conclusion, ARFRP1 and the Golgi apparatus play an important role in lipoprotein maturation in the liver by influencing lipidation and assembly of proteins to the lipid particles. PMID:24186947

Cholesterol delivery to the adrenal glands estimated by adrenal venous sampling: An in vivo model to determine the contribution of circulating lipoproteins to steroidogenesis in humans.

Science.gov (United States)

Buitenwerf, Edward; Dullaart, Robin P F; Muller Kobold, Anneke C; Links, Thera P; Sluiter, Wim J; Connelly, Margery A; Kerstens, Michiel N

Cholesterol, required for adrenal steroid hormone synthesis, is at least in part derived from circulating lipoproteins. The contribution of high-density lipoproteins (HDL) and low-density lipoproteins (LDL) to adrenal steroidogenesis in humans is unclear. The aim of the study was to determine the extent to which HDL and LDL are taken up by the adrenal glands using samples obtained during adrenal venous sampling (AVS). AVS was successfully performed in 23 patients with primary aldosteronism. Samples were drawn from both adrenal veins and inferior vena cava (IVC). HDL cholesterol (HDL-C) and lipoprotein particle profiles were determined by nuclear magnetic resonance spectroscopy. Apolipoprotein (apo) A-I and apoB were assayed by immunoturbidimetry. Plasma HDL-C and HDL and LDL particle concentrations (HDL-P and LDL-P) were not lower in samples obtained from the adrenal veins compared with the IVC (HDL-C, P = .59; HDL-P, P = .06; LDL-P, P = .93). ApoB was lower in adrenal venous plasma than in IVC (P = .026; P lipoproteins and steroidogenesis. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Reconstituted high-density lipoprotein infusion modulates fatty acid metabolism in patients with type 2 diabetes mellitus

DEFF Research Database (Denmark)

Drew, BG; Carey, AL; Natoli, AK

2011-01-01

We recently demonstrated that reconstituted high-density lipoprotein (rHDL) modulates glucose metabolism in humans via both AMP-activated protein kinase (AMPK) in muscle and by increasing plasma insulin. Given the key roles of both AMPK and insulin in fatty acid metabolism, the current study inve...

Effects of oxygen plasma treatment on domestic aramid fiber III reinforced bismaleimide composite interfacial properties

Science.gov (United States)

Shi, Chen; Wang, Jing; Chen, Ping; Feng, Jiayue; Cui, Jinyuan; Yang, Faze

2017-12-01

Domestic Aramid Fiber III (DAF III) was modified by oxygen plasma treatment. The fiber surface characteristics was observed by Scanning Electron Microscopy. The results showed that oxygen plasma treatment changed surface morphologies. The effects of oxygen plasma treatment on DAF III reinforced bismaleimides (BMI) composite bending and interfacial properties were investigated, respectively. The ILSS value increased from 49.3 MPa to 56.0 MPa (by 13.5%) after oxygen plasma treatment. The bending strength changed a little. Furthermore, the composite rupture mode changed from interfacial rupture to fiber or resin bulk rupture.

Composite plasma polymerized sulfonated polystyrene membrane for PEMFC

Energy Technology Data Exchange (ETDEWEB)

Nath, Bhabesh Kumar; Khan, Aziz; Chutia, Joyanti, E-mail: jchutiaiasst@gmail.com

2015-10-15

Highlights: • Methyl methane sulfonate (MMS) is used as the sulfonating agent. • The proton conductivity of the membrane is found to be 0.141 S cm{sup −1}. • Power density of fuel cell with styrene/MMS membrane is 0.5 W cm{sup −2}. • The membrane exhibits thermal stability up to 140 °C. - Abstract: This work presents the introduction of an organic compound methyl methane sulfonate (MMS) for the first time in fabrication of polystyrene based proton exchange membrane (PEM) by plasma polymerization process. The membrane is fabricated by co-polymerizing styrene and MMS in capacitively coupled continuous RF plasma. The chemical composition of the plasma polymerized polymer membrane is investigated using Fourier Transform Infrared Spectroscopy which reveals the formation of composite structure of styrene and MMS. The surface morphology studied using AFM and SEM depicts the effect of higher partial pressure of MMS on surface topography of the membrane. The proton transport property of the membrane studied using electrochemical impedance spectroscopy shows the achievement of maximum proton conductivity of 0.141 S cm{sup −1} which is comparable to Nafion 117 membrane. Fuel cell performance test of the synthesized membrane shows a maximum power density of 500 mW cm{sup −2} and current density of 0.62 A cm{sup −2} at 0.6 V.

Survey of 0.1- to 16-keV/e plasma sheet ion composition

International Nuclear Information System (INIS)

Lennartsson, W.; Shelley, E.G.

1986-01-01

A large statistical survey of the 0.1- to 16-keV/e plasma sheet ion composition has been carried out using data obtained by the Plasma Composition Experiment on ISEE 1 between 10 and 23 R/sub E/ during 1978 and 1979. This survey includes more than 10 times the quantity of data used in earlier studies of the same topic and makes it possible to investigate in finer detail the relationship between the ion composition and the substorm activity. The larger data base also makes it possible for the first time to study the spatial distribution of the principal ion species. As found in previous studies, the ion composition has a large variance at any given value of the AE index, but a number of distinct trends emerge when the data are averaged at each activity level. During quiet conditions the plasma sheet is dominated by ions of solar origin (H + and He ++ ), as found in earlier studies, and these ions are most numerous during extended periods of very low activity (AE< or approx. =30 γ). The quiet time density of these ions is particularly large in the flanks of the plasma sheet (GSM Yapprox. +- 10 R/sub E/), where it is about twice as large as it is near the central axis of the plasma sheet (Y = Z = 0). In contrast, the energy of these ions peaks near the central axis

Genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the rat.

Directory of Open Access Journals (Sweden)

Miloslava Hodúlová

Full Text Available The plasma profile of major lipoprotein classes and its subdivision into particular fractions plays a crucial role in the pathogenesis of atherosclerosis and is a major predictor of coronary artery disease. Our aim was to identify genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions and lipoprotein particle sizes in the recombinant inbred rat set PXO, in which alleles of two rat models of the metabolic syndrome (SHR and PD inbred strains segregate together with those from Brown Norway rat strain. Adult male rats of 15 PXO strains (n = 8-13/strain and two progenitor strains SHR-Lx (n = 13 and BXH2/Cub (n = 18 were subjected to one-week of high-sucrose diet feeding. We performed association analyses of triglyceride (TG and cholesterol (C concentrations in 20 lipoprotein fractions and the size of major classes of lipoprotein particles utilizing 704 polymorphic microsatellite markers, the genome-wide significance was validated by 2,000 permutations per trait. Subsequent in silico focusing of the identified quantitative trait loci was completed using a map of over 20,000 single nucleotide polymorphisms. In most of the phenotypes we identified substantial gradient among the strains (e.g. VLDL-TG from 5.6 to 66.7 mg/dl. We have identified 14 loci (encompassing 1 to 65 genes on rat chromosomes 3, 4, 7, 8, 11 and 12 showing suggestive or significant association to one or more of the studied traits. PXO strains carrying the SHR allele displayed significantly higher values of the linked traits except for LDL-TG and adiposity index. Cholesterol concentrations in large, medium and very small LDL particles were significantly associated to a haplotype block spanning part of a single gene, low density lipoprotein receptor-related protein 1B (Lrp1b. Using genome-wide association we have identified new genetic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the recombinant

Overall glycemic index and glycemic load of vegan diets in relation to plasma lipoproteins and triacylglycerols.

Science.gov (United States)

Waldmann, Annika; Ströhle, Alexander; Koschizke, Jochen W; Leitzmann, Claus; Hahn, Andreas

2007-01-01

To investigate the overall glycemic index (GI), glycemic load (GL), and intake of dietary fiber, and to examine the associations between these factors and plasma lipoproteins and triacylglycerols in adult vegans in the German Vegan Study (GVS). Cross-sectional study, Germany. Healthy men (n = 67) and women (n = 87), who fulfilled the study criteria (vegan diet for >or=1 year prior to study start; minimum age of 18 years; no pregnancy/childbirth during the last 12 months) and who participated in all study segments. The average dietary GL of the GVS population was 144, and the average GI was 51.4. The adjusted geometric mean total, HDL, and LDL cholesterol concentrations decreased across the increasing quartiles of GL, carbohydrate and dietary fiber intake. The associations between total cholesterol, HDL cholesterol, LDL cholesterol and GL density and GI were inconsistent. Also, associations between GI, GL, the intake of carbohydrates, and triacylglycerol concentration were not observed. Fiber-rich vegan diets are characterized by a low GI and a low to moderate GL. The data do not support the hypothesis that a carbohydrate-rich diet per se is associated with unfavorable effects on triaclyglycerols that would be predicted to increase the risk of coronary heart disease. Copyright (c) 2007 S. Karger AG, Basel.

Triglyceride-rich lipoproteins as a causal factor for cardiovascular disease

Science.gov (United States)

Toth, Peter P

2016-01-01

Approximately 25% of US adults are estimated to have hypertriglyceridemia (triglyceride [TG] level ≥150 mg/dL [≥1.7 mmol/L]). Elevated TG levels are associated with increased cardiovascular disease (CVD) risk, and severe hypertriglyceridemia (TG levels ≥500 mg/dL [≥5.6 mmol/L]) is a well-established risk factor for acute pancreatitis. Plasma TG levels correspond to the sum of the TG content in TG-rich lipoproteins (TRLs; ie, very low-density lipoproteins plus chylomicrons) and their remnants. There remains some uncertainty regarding the direct causal role of TRLs in the progression of atherosclerosis and CVD, with cardiovascular outcome studies of TG-lowering agents, to date, having produced inconsistent results. Although low-density lipoprotein cholesterol (LDL-C) remains the primary treatment target to reduce CVD risk, a number of large-scale epidemiological studies have shown that elevated TG levels are independently associated with increased incidence of cardiovascular events, even in patients treated effectively with statins. Genetic studies have further clarified the causal association between TRLs and CVD. Variants in several key genes involved in TRL metabolism are strongly associated with CVD risk, with the strength of a variant’s effect on TG levels correlating with the magnitude of the variant’s effect on CVD. TRLs are thought to contribute to the progression of atherosclerosis and CVD via a number of direct and indirect mechanisms. They directly contribute to intimal cholesterol deposition and are also involved in the activation and enhancement of several proinflammatory, proapoptotic, and procoagulant pathways. Evidence suggests that non-high-density lipoprotein cholesterol, the sum of the total cholesterol carried by atherogenic lipoproteins (including LDL, TRL, and TRL remnants), provides a better indication of CVD risk than LDL-C, particularly in patients with hypertriglyceridemia. This article aims to provide an overview of the

Triglyceride-rich lipoproteins as a causal factor for cardiovascular disease.

Science.gov (United States)

Toth, Peter P

2016-01-01

Approximately 25% of US adults are estimated to have hypertriglyceridemia (triglyceride [TG] level ≥150 mg/dL [≥1.7 mmol/L]). Elevated TG levels are associated with increased cardiovascular disease (CVD) risk, and severe hypertriglyceridemia (TG levels ≥500 mg/dL [≥5.6 mmol/L]) is a well-established risk factor for acute pancreatitis. Plasma TG levels correspond to the sum of the TG content in TG-rich lipoproteins (TRLs; ie, very low-density lipoproteins plus chylomicrons) and their remnants. There remains some uncertainty regarding the direct causal role of TRLs in the progression of atherosclerosis and CVD, with cardiovascular outcome studies of TG-lowering agents, to date, having produced inconsistent results. Although low-density lipoprotein cholesterol (LDL-C) remains the primary treatment target to reduce CVD risk, a number of large-scale epidemiological studies have shown that elevated TG levels are independently associated with increased incidence of cardiovascular events, even in patients treated effectively with statins. Genetic studies have further clarified the causal association between TRLs and CVD. Variants in several key genes involved in TRL metabolism are strongly associated with CVD risk, with the strength of a variant's effect on TG levels correlating with the magnitude of the variant's effect on CVD. TRLs are thought to contribute to the progression of atherosclerosis and CVD via a number of direct and indirect mechanisms. They directly contribute to intimal cholesterol deposition and are also involved in the activation and enhancement of several proinflammatory, proapoptotic, and procoagulant pathways. Evidence suggests that non-high-density lipoprotein cholesterol, the sum of the total cholesterol carried by atherogenic lipoproteins (including LDL, TRL, and TRL remnants), provides a better indication of CVD risk than LDL-C, particularly in patients with hypertriglyceridemia. This article aims to provide an overview of the available

Plasma Polypyrrole Coated Hybrid Composites with Improved Mechanical and Electrical Properties for Aerospace Applications

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Yavuz, Hande; Bai, Jinbo

2018-06-01

This paper deals with the dielectric barrier discharge assisted continuous plasma polypyrrole deposition on CNT-grafted carbon fibers for conductive composite applications. The simultaneous effects of three controllable factors have been studied on the electrical resistivity (ER) of these two material systems based on multivariate experimental design methodology. A posterior probability referring to Benjamini-Hochberg (BH) false discovery rate was explored as multiple testing corrections of the t-test p values. BH significance threshold of 0.05 was produced truly statistically significant coefficients to describe ER of two material systems. A group of plasma modified samples was chosen to be used for composite manufacturing to drive an assessment of interlaminar shear properties under static loading. Transversal and longitudinal electrical resistivity (DC, ω =0) of composite samples were studied to compare both the effects of CNT grafting and plasma modification on ER of resultant composites.

Plasma Polypyrrole Coated Hybrid Composites with Improved Mechanical and Electrical Properties for Aerospace Applications

Science.gov (United States)

Yavuz, Hande; Bai, Jinbo

2017-09-01

This paper deals with the dielectric barrier discharge assisted continuous plasma polypyrrole deposition on CNT-grafted carbon fibers for conductive composite applications. The simultaneous effects of three controllable factors have been studied on the electrical resistivity (ER) of these two material systems based on multivariate experimental design methodology. A posterior probability referring to Benjamini-Hochberg (BH) false discovery rate was explored as multiple testing corrections of the t-test p values. BH significance threshold of 0.05 was produced truly statistically significant coefficients to describe ER of two material systems. A group of plasma modified samples was chosen to be used for composite manufacturing to drive an assessment of interlaminar shear properties under static loading. Transversal and longitudinal electrical resistivity (DC, ω =0) of composite samples were studied to compare both the effects of CNT grafting and plasma modification on ER of resultant composites.

RRR- and SRR-alpha-tocopherols are secreted without discrimination in human chylomicrons, but RRR-alpha-tocopherol is preferentially secreted in very low density lipoproteins

International Nuclear Information System (INIS)

Traber, M.G.; Burton, G.W.; Ingold, K.U.; Kayden, H.J.

1990-01-01

Five subjects ingested in a single oral dose containing 50 mg each of 2R,4'R,8'R-alpha-(5,7-(C2H3)2)tocopheryl acetate (d6-RRR-alpha-tocopheryl acetate) with natural stereochemistry, and of 2S,4'R,8'R-alpha-(5-C2H3)tocopheryl acetate (d3-SRR-alpha-tocopheryl acetate). These are two of eight stereoisomers in synthetic vitamin E. By day 1 the plasma and red blood cells were enriched fourfold with d6-RRR-alpha-tocopherol (P less than 0.004). The ratio of d6-RRR-/d2-SRR- further increased over the succeeding 4 days, because the d3-SRR- decreased at a faster rate than did the d6-RRR-stereoisomer. Plasma and lipoproteins were isolated at intervals during the first day, and daily for 3 days, from four additional subjects fed a mixture of equal amounts of the deuterated tocopherols. The plasma contained similar concentrations of the two forms until 11 h, when the d6-RRR-alpha-tocopherol concentration became significantly greater (P less than 0.05). The chylomicrons contained similar concentrations of the two deuterated tocopherols, but the VLDL (very low density lipoproteins) became preferentially enriched in d6-RRR-alpha-tocopherol by 11 h. The pattern of the deuterated tocopherols shows that during chylomicron catabolism all of the plasma lipoproteins were labeled equally with both tocopherols, but that during the subsequent VLDL catabolism the low and high density lipoproteins became enriched in d6-RRR-alpha-tocopherol. These results suggest the existence of a mechanism in the liver for assembling VLDL preferentially enriched in RRR- relative to SRR-alpha-tocopherol

High hydrostatic pressure specifically affects molecular dynamics and shape of low-density lipoprotein particles

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Golub, M.; Lehofer, B.; Martinez, N.; Ollivier, J.; Kohlbrecher, J.; Prassl, R.; Peters, J.

2017-04-01

Lipid composition of human low-density lipoprotein (LDL) and its physicochemical characteristics are relevant for proper functioning of lipid transport in the blood circulation. To explore dynamical and structural features of LDL particles with either a normal or a triglyceride-rich lipid composition we combined coherent and incoherent neutron scattering methods. The investigations were carried out under high hydrostatic pressure (HHP), which is a versatile tool to study the physicochemical behavior of biomolecules in solution at a molecular level. Within both neutron techniques we applied HHP to probe the shape and degree of freedom of the possible motions (within the time windows of 15 and 100 ps) and consequently the flexibility of LDL particles. We found that HHP does not change the types of motion in LDL, but influences the portion of motions participating. Contrary to our assumption that lipoprotein particles, like membranes, are highly sensitive to pressure we determined that LDL copes surprisingly well with high pressure conditions, although the lipid composition, particularly the triglyceride content of the particles, impacts the molecular dynamics and shape arrangement of LDL under pressure.

Triglyceride-rich lipoprotein metabolism in women: roles of apoC-II and apoC-III.

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Ooi, Esther M; Chan, Dick C; Hodson, Leanne; Adiels, Martin; Boren, Jan; Karpe, Fredrik; Fielding, Barbara A; Watts, Gerald F; Barrett, P Hugh R

2016-08-01

Experimental data suggest that apolipoprotein (apo) C-II and C-III regulate triglyceride-rich lipoprotein (TRL) metabolism, but there are limited studies in humans. We investigated the metabolic associations of TRLs with apoC-II and apoC-III concentrations and kinetics in women. The kinetics of plasma apoC-II, apoC-III and very low-density lipoprotein (VLDL) apoB-100 and triglycerides were measured in the postabsorptive state using stable isotopic techniques and compartmental modelling in 60 women with wide-ranging body mass index (19·5-32·9 kg/m(2) ). Plasma apoC-II and apoC-III concentrations were positively associated with the concentrations of plasma triglycerides, VLDL1 - and VLDL2 -apoB-100 and triglyceride (all P triglyceride concentration and VLDL1 triglyceride PR, while apoC-II fractional catabolic rate (FCR) was positively associated with VLDL1 triglyceride FCR (all P triglyceride kinetics. ApoC-III PR, but not FCR, was positively associated with VLDL1 triglyceride, and VLDL2 -apoB-100 and triglyceride concentrations (all P triglyceride kinetics. In multivariable analysis, including homoeostasis model assessment score, menopausal status and obesity, apoC-II concentration was significantly associated with plasma triglyceride, VLDL1 -apoB-100 and VLDL1 triglyceride concentrations and PR. Using the same multivariable analysis, apoC-III was significantly associated with plasma triglyceride and VLDL1 - and VLDL2 -apoB-100 and triglyceride concentrations and FCR. In women, plasma apoC-II and apoC-III concentrations are regulated by their respective PR and are significant, independent determinants of the kinetics and plasma concentrations of TRLs. © 2016 Stichting European Society for Clinical Investigation Journal Foundation.

Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study

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BACKGROUND: Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphism...

α-Defensins Induce a Post-translational Modification of Low Density Lipoprotein (LDL) That Promotes Atherosclerosis at Normal Levels of Plasma Cholesterol.

Science.gov (United States)

Abu-Fanne, Rami; Maraga, Emad; Abd-Elrahman, Ihab; Hankin, Aviel; Blum, Galia; Abdeen, Suhair; Hijazi, Nuha; Cines, Douglas B; Higazi, Abd Al-Roof

2016-02-05

Approximately one-half of the patients who develop clinical atherosclerosis have normal or only modest elevations in plasma lipids, indicating that additional mechanisms contribute to pathogenesis. In view of increasing evidence that inflammation contributes to atherogenesis, we studied the effect of human neutrophil α-defensins on low density lipoprotein (LDL) trafficking, metabolism, vascular deposition, and atherogenesis using transgenic mice expressing human α-defensins in their polymorphonuclear leukocytes (Def(+/+)). Accelerated Def(+/+) mice developed α-defensin·LDL complexes that accelerate the clearance of LDL from the circulation accompanied by enhanced vascular deposition and retention of LDL, induction of endothelial cathepsins, increased endothelial permeability to LDL, and the development of lipid streaks in the aortic roots when fed a regular diet and at normal plasma levels of LDL. Transplantation of bone marrow from Def(+/+) to WT mice increased LDL clearance, increased vascular permeability, and increased vascular deposition of LDL, whereas transplantation of WT bone marrow to Def(+/+) mice prevented these outcomes. The same outcome was obtained by treating Def(+/+) mice with colchicine to inhibit the release of α-defensins. These studies identify a potential new link between inflammation and the development of atherosclerosis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Effects of growth hormone and testosterone therapy on aerobic and anaerobic fitness , body composition and lipoprotein profile in middle-aged men

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Adam Zając

2014-03-01

Full Text Available Introduction. Andropause and aging are associated with neuroendocrine dysfunctions. Growth hormone and testosterone play a significant role in several processes affecting adaptation and thereby also everyday functioning. The aim of this research project was to evaluate the effects of recombinant human growth hormone and testosterone enanthate injections on body mass and body composition, aerobic and anaerobic fitness and lipid profile in middle-aged men. Materials and method. The research group was comprised of 14 men aged 45 – 60 years. Two series of laboratory analyses were performed. Independent tests were carried out at baseline and after 12 weeks of the experiment. The data were analyzed using Statistica 9.1 software. Results. A two-way repeated measures ANOVA revealed a statistically significant effect of the intervention programme on fat-free mass (η2=0.34, total body fat (η2=0.79, total cholesterol (η2=0.30, high-density lipoprotein cholesterol (η2=0.31, low-density lipoprotein cholesterol (η2=0.42, triglyceride (η2=0.28, testosterone (η2=0.52, insulin-like growth factor 1 (η2=0.47 and growth hormone (η2=0.63. Furthermore, ANOVA revealed a statistically significant effect of the rhGH and T treatment on maximal oxygen uptake (η2=0.63, anaerobic threshold (η2=0.61 and maximal work rate (η2=0.53. Conclusion. It should be emphasized that the lipid profile was affected not only by rhGH+T replacement therapy, but also by the prescribed physical activity programme. The strength and endurance fitness programme alone did not cause significant changes in body mass and composition, nor the anaerobic and aerobic capacity. On the other hand, the rhGH=T treatment stimulated these changes significantly.

Domains of apolipoprotein E contributing to triglyceride and cholesterol homeostasis in vivo. Carboxyl-terminal region 203-299 promotes hepatic very low density lipoprotein-triglyceride secretion

NARCIS (Netherlands)

Kypreos, K.E.; Dijk, K.W. van; Zee, A. van der; Havekes, L.M.; Zannis, V.I.

2001-01-01

Apolipoprotein (apo) E has been implicated in cholesterol and triglyceride homeostasis in humans. At physiological concentration apoE promotes efficient clearance of apoE-containing lipoprotein remnants. However, high apoE plasma levels correlate with high plasma triglyceride levels. We have used

Low-density lipoprotein electronegativity is a novel cardiometabolic risk factor.

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Jing-Fang Hsu

Full Text Available BACKGROUND: Low-density lipoprotein (LDL plays a central role in cardiovascular disease (CVD development. In LDL chromatographically resolved according to charge, the most electronegative subfraction-L5-is the only subfraction that induces atherogenic responses in cultured vascular cells. Furthermore, increasing evidence has shown that plasma L5 levels are elevated in individuals with high cardiovascular risk. We hypothesized that LDL electronegativity is a novel index for predicting CVD. METHODS: In 30 asymptomatic individuals with metabolic syndrome (MetS and 27 healthy control subjects, we examined correlations between plasma L5 levels and the number of MetS criteria fulfilled, CVD risk factors, and CVD risk according to the Framingham risk score. RESULTS: L5 levels were significantly higher in MetS subjects than in control subjects (21.9±18.7 mg/dL vs. 11.2±10.7 mg/dL, P:0.01. The Jonckheere trend test revealed that the percent L5 of total LDL (L5% and L5 concentration increased with the number of MetS criteria (P<0.001. L5% correlated with classic CVD risk factors, including waist circumference, body mass index, waist-to-height ratio, smoking status, blood pressure, and levels of fasting plasma glucose, triglyceride, and high-density lipoprotein. Stepwise regression analysis revealed that fasting plasma glucose level and body mass index contributed to 28% of L5% variance. The L5 concentration was associated with CVD risk and contributed to 11% of 30-year general CVD risk variance when controlling the variance of waist circumference. CONCLUSION: Our findings show that LDL electronegativity was associated with multiple CVD risk factors and CVD risk, suggesting that the LDL electronegativity index may have the potential to be a novel index for predicting CVD. Large-scale clinical trials are warranted to test the reliability of this hypothesis and the clinical importance of the LDL electronegativity index.

Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

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Zhang, Huanxia; Li, Wei

2015-11-01

Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid-base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as Csbnd O, Cdbnd O, and Osbnd Cdbnd O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the plasma-grafting treatments.

Mice with chimeric livers are an improved model for human lipoprotein metabolism.

Science.gov (United States)

Ellis, Ewa C S; Naugler, Willscott Edward; Nauglers, Scott; Parini, Paolo; Mörk, Lisa-Mari; Jorns, Carl; Zemack, Helen; Sandblom, Anita Lövgren; Björkhem, Ingemar; Ericzon, Bo-Göran; Wilson, Elizabeth M; Strom, Stephen C; Grompe, Markus

2013-01-01

Rodents are poor model for human hyperlipidemias because total cholesterol and low density lipoprotein levels are very low on a normal diet. Lipoprotein metabolism is primarily regulated by hepatocytes and we therefore assessed whether chimeric mice extensively repopulated with human cells can model human lipid and bile acid metabolism. FRG [ F ah(-/-) R ag2(-/-)Il2r g (-/-)]) mice were repopulated with primary human hepatocytes. Serum lipoprotein lipid composition and distribution (VLDL, LDL, and HDL) was analyzed by size exclusion chromatography. Bile was analyzed by LC-MS or by GC-MS. RNA expression levels were measured by quantitative RT-PCR. Chimeric mice displayed increased LDL and VLDL fractions and a lower HDL fraction compared to wild type, thus significantly shifting the ratio of LDL/HDL towards a human profile. Bile acid analysis revealed a human-like pattern with high amounts of cholic acid and deoxycholic acid (DCA). Control mice had only taurine-conjugated bile acids as expcted, but highly repopulated mice had glycine-conjugated cholic acid as found in human bile. RNA levels of human genes involved in bile acid synthesis including CYP7A1, and CYP27A1 were significantly upregulated as compared to human control liver. However, administration of recombinant hFGF19 restored human CYP7A1 levels to normal. Humanized-liver mice showed a typical human lipoprotein profile with LDL as the predominant lipoprotein fraction even on a normal diet. The bile acid profile confirmed presence of an intact enterohepatic circulation. Although bile acid synthesis was deregulated in this model, this could be fully normalized by FGF19 administration. Taken together these data indicate that chimeric FRG-mice are a useful new model for human lipoprotein and bile-acid metabolism.

Familial defective apolipoprotein B-100: low density lipoproteins with abnormal receptor binding

International Nuclear Information System (INIS)

Innerarity, T.L.; Weisgraber, K.H.; Arnold, K.S.; Mahley, R.W.; Krauss, R.M.; Vega, G.L.; Grundy, S.M.

1987-01-01

Previous in vivo turnover studies suggested that retarded clearance of low density lipoproteins (LDL) from the plasma of some hypercholesterolemic patients is due to LDL with defective receptor binding. The present study examined this postulate directly by receptor binding experiments. The LDL from a hypercholesterolemic patient (G.R.) displayed a reduced ability to bind to the LDL receptors on normal human fibroblasts. The G.R. LDL possessed 32% of normal receptor binding activity. Likewise, the G.R. LDL were much less effective than normal LDL in competing with 125 I-labeled normal LDL for cellular uptake and degradation and in stimulating intracellular cholesteryl ester synthesis. The defect in LDL binding appears to be due to a genetic abnormality of apolipoprotein B-100: two brothers of the proband possess LDL defective in receptor binding, whereas a third brother and the proband's son have normally binding LDL. Further, the defect in receptor binding does not appear to be associated wit an abnormal lipid composition or structure of the LDL. Normal and abnormal LDL subpopulations were partially separated from plasma of two subjects by density-gradient ultracentrifugation, a finding consistent with the presence of a normal and a mutant allele. The affected family members appear to be heterozygous for this disorder, which has been designated familial defective apolipoprotein B-100. These studies indicate that the defective receptor binding results in inefficient clearance of LDL and the hypercholesterolemia observed in these patients

Loci of catabolism of beta-very low density lipoprotein in vivo delineated with a residualizing label, 125I-dilactitol tyramine

International Nuclear Information System (INIS)

Daugherty, A.; Thorpe, S.R.; Lange, L.G.; Sobel, B.E.; Schonfeld, G.

1985-01-01

beta-Very low density lipoprotein (beta-VLDL) may be a major atherogenic lipoprotein, and knowledge of the sites of its catabolism should facilitate elucidation of mechanisms important in the regulation of its plasma concentrations. In this study, catabolic sites of beta-VLDL have been delineated in normolipidemic rabbits with a novel, radioiodinated, residualizing label, 125 I-dilactitol tyramine ( 125 I-DLT). Comparative studies of beta-VLDL and low density lipoprotein catabolism were performed with 125 I-DLT conjugated to each lipoprotein and with lipoproteins iodine-labeled conventionally. Conjugation did not alter size distributions or charge characteristics of lipoprotein particles. The overall processing (binding and degradation) of lipoproteins by cultured rabbit skin fibroblasts was not influenced by 125 I-DLT derivatization, suggesting that attachment of the label did not influence cell receptor-lipoprotein interactions. Furthermore, although degradation products of 125 I-lipoproteins leaked out of the cells and into the medium, the degradation products of 125 I-DLT lipoproteins were retained by the cells. The principal catabolic site of beta-VLDL in normolipidemic rabbits was found to be the liver with 54 +/- 4% of injected 125 I retained in this organ 24 h after injection of 125 I-DLT-beta-VLDL. When catabolism was normalized to tissue weight, the liver and adrenals were found to be approximately equally active in the metabolism of beta-VLDL. In agreement with results of other studies with residualizing labels, the principal organ of catabolism of 125 I-DLT-LDL in vivo was the liver. The adrenals were the most highly catabolizing organ when results were normalized for tissue weight

Lipoprotein metabolism indicators improve cardiovascular risk prediction.

Directory of Open Access Journals (Sweden)

Daniël B van Schalkwijk

Full Text Available 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 Discrimination Improvement (IDI. Two VLDL lipoprotein metabolism indicators (VLDLE and VLDLH improved cardiovascular risk prediction. We added these indicators to a multivariate model with the best performing conventional risk markers. Our method significantly improved both CVD prediction and risk reclassification. CONCLUSIONS: Two calculated VLDL metabolism indicators significantly improved cardiovascular risk prediction. These indicators may help to reduce prescription of unnecessary cholesterol-lowering medication, reducing costs and possible side-effects. For clinical application, further validation is required.

n-3 Polyunsaturated Fatty Acid Supplementation Has No Effect on Postprandial Triglyceride-Rich Lipoprotein Kinetics in Men with Type 2 Diabetes

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André J. Tremblay

2016-01-01

Full Text Available Dietary n-3 polyunsaturated fatty acids (PUFAs have been proposed to modulate plasma lipids, lipoprotein metabolism, and inflammatory state and to reduce triglyceride (TG concentrations. The present double-blind, randomized, placebo-controlled, crossover study investigated the effects of n-3 PUFA supplementation at 3 g/d for 8 weeks on the intravascular kinetics of intestinally derived apolipoprotein (apo B-48-containing lipoproteins in 10 men with type 2 diabetes. In vivo kinetics of the TG-rich lipoprotein (TRL apoB-48 and VLDL apoB-100 were assessed using a primed-constant infusion of L-[5,5,5-D3] leucine for 12 hours in a fed state. Compared with the placebo, n-3 PUFA supplementation significantly reduced fasting TG concentrations by −9.7% (P=0.05 but also significantly increased plasma levels of cholesterol (C (+6.0%, P=0.05, LDL-C (+12.2%, P=0.04, and HDL-C (+8.4, P=0.007. n-3 PUFA supplementation had no significant impact on postprandial TRL apoB-48 and VLDL apoB-100 levels or on the production or catabolic rates of these lipoproteins. These data indicate that 8-week supplementation with n-3 PUFAs in men with type 2 diabetes has no beneficial effect on TRL apoB-48 and VLDL apoB-100 levels or kinetics.

Bacterial lipoproteins; biogenesis, sorting and quality control.

Science.gov (United States)

Narita, Shin-Ichiro; Tokuda, Hajime

2017-11-01

Bacterial lipoproteins are a subset of membrane proteins localized on either leaflet of the lipid bilayer. These proteins are anchored to membranes through their N-terminal lipid moiety attached to a conserved Cys. Since the protein moiety of most lipoproteins is hydrophilic, they are expected to play various roles in a hydrophilic environment outside the cytoplasmic membrane. Gram-negative bacteria such as Escherichia coli possess an outer membrane, to which most lipoproteins are sorted. The Lol pathway plays a central role in the sorting of lipoproteins to the outer membrane after lipoprotein precursors are processed to mature forms in the cytoplasmic membrane. Most lipoproteins are anchored to the inner leaflet of the outer membrane with their protein moiety in the periplasm. However, recent studies indicated that some lipoproteins further undergo topology change in the outer membrane, and play critical roles in the biogenesis and quality control of the outer membrane. This article is part of a Special Issue entitled: Bacterial Lipids edited by Russell E. Bishop. Copyright © 2016 Elsevier B.V. All rights reserved.

Regulation of plasma LDL: the apoB paradigm.

NARCIS (Netherlands)

Sniderman, A.D.; Graaf, J. de; Couture, P.; Williams, K.; Kiss, R.S.; Watts, G.F.

2010-01-01

The objectives of this analysis are to re-examine the foundational studies of the in vivo metabolism of plasma LDL (low-density lipoprotein) particles in humans and, based on them, to reconstruct our understanding of the governance of the concentration of plasma LDL and the maintenance of

Lipoprotein metabolism indicators improve cardiovascular risk prediction

NARCIS (Netherlands)

Schalkwijk, D.B. van; Graaf, A.A. de; Tsivtsivadze, E.; Parnell, L.D.; Werff-van der Vat, B.J.C. van der; Ommen, B. van; Greef, J. van der; Ordovás, J.M.

2014-01-01

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

Corn oil improves the plasma lipoprotein lipid profile compared with extra-virgin olive oil consumption in men and women with elevated cholesterol: results from a randomized controlled feeding trial.

Science.gov (United States)

Maki, Kevin C; Lawless, Andrea L; Kelley, Kathleen M; Kaden, Valerie N; Geiger, Constance J; Dicklin, Mary R

2015-01-01

Restricted intakes of saturated and trans-fatty acids is emphasized in heart-healthy diets, and replacement with poly- and monounsaturated fatty acids is encouraged. To compare the effects of polyunsaturated fatty acid-rich corn oil (CO) and monounsaturated fatty acid-rich extra-virgin olive oil (EVOO) on plasma lipids in men and women (N = 54) with fasting low-density lipoprotein cholesterol (LDL-C) ≥130 mg/dL and consumption away from the clinic. Baseline mean (standard error) lipids in mg/dL were: LDL-C 153.3 (3.5), total cholesterol (total-C) 225.7 (3.9), non-high-density lipoprotein (non-HDL)-C 178.3 (3.7), HDL-C 47.4 (1.7), total-C/HDL-C 5.0 (0.2), and TG 124.8 (7.2). CO resulted in significantly larger least-squares mean % changes (all P Consumption of CO in a weight-maintenance, low saturated fat and cholesterol diet resulted in more favorable changes in LDL-C and other atherogenic lipids vs EVOO. Copyright © 2015 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Composite film fabricated on biomedical material with corona streamer plasma processing to mitigate bacterial adhesion

Science.gov (United States)

Alhamarneh, Ibrahim; Pedrow, Patrick; Eskhan, Asma; Abu-Lail, Nehal

2011-10-01

Composite films might control bacterial adhesion and concomitant biofouling that afflicts biomedical materials. Different size molecules of polyethylene glycol (PEG) with nominal molecular weights 600, 2000, and 20000 g/mol were used to synthesize composite films with plasma processing and dip-coating procedures on surgical-grade 316L stainless steel. Before dip-coating, the substrate was pre-coated with plasma-polymerized di(ethylene glycol) vinyl ether (pp-EO2V) in an atmospheric pressure corona streamer plasma reactor. The PEG dip-coating step followed immediately in the same chamber due to the finite lifetime of radicals associated with freshly deposited pp-EO2V. Morphology of the composite film was investigated with an ESEM. FTIR confirmed incorporation of pp-EO2V and PEG species into the composite film. More investigations on the composite film were conducted by XPS measurements. Adhesion of the composite film was evaluated with a standard peel-off test. Stability of the composite film in buffer solution was evaluated by AFM. AFM was also used to measure the film roughness and thickness. Polar and non-polar contact angle measurements were included.

Common variants associated with plasma triglycerides and risk for coronary artery disease.

Science.gov (United States)

Do, Ron; Willer, Cristen J; Schmidt, Ellen M; Sengupta, Sebanti; Gao, Chi; Peloso, Gina M; Gustafsson, Stefan; Kanoni, Stavroula; Ganna, Andrea; Chen, Jin; Buchkovich, Martin L; Mora, Samia; Beckmann, Jacques S; Bragg-Gresham, Jennifer L; Chang, Hsing-Yi; Demirkan, Ayşe; Den Hertog, Heleen M; Donnelly, Louise A; Ehret, Georg B; Esko, Tõnu; Feitosa, Mary F; Ferreira, Teresa; Fischer, Krista; Fontanillas, Pierre; Fraser, Ross M; Freitag, Daniel F; Gurdasani, Deepti; Heikkilä, Kauko; Hyppönen, Elina; Isaacs, Aaron; Jackson, Anne U; Johansson, Asa; Johnson, Toby; Kaakinen, Marika; Kettunen, Johannes; Kleber, Marcus E; Li, Xiaohui; Luan, Jian'an; Lyytikäinen, Leo-Pekka; Magnusson, Patrik K E; Mangino, Massimo; Mihailov, Evelin; Montasser, May E; Müller-Nurasyid, Martina; Nolte, Ilja M; O'Connell, Jeffrey R; Palmer, Cameron D; Perola, Markus; Petersen, Ann-Kristin; Sanna, Serena; Saxena, Richa; Service, Susan K; Shah, Sonia; Shungin, Dmitry; Sidore, Carlo; Song, Ci; Strawbridge, Rona J; Surakka, Ida; Tanaka, Toshiko; Teslovich, Tanya M; Thorleifsson, Gudmar; Van den Herik, Evita G; Voight, Benjamin F; Volcik, Kelly A; Waite, Lindsay L; Wong, Andrew; Wu, Ying; Zhang, Weihua; Absher, Devin; Asiki, Gershim; Barroso, Inês; Been, Latonya F; Bolton, Jennifer L; Bonnycastle, Lori L; Brambilla, Paolo; Burnett, Mary S; Cesana, Giancarlo; Dimitriou, Maria; Doney, Alex S F; Döring, Angela; Elliott, Paul; Epstein, Stephen E; Eyjolfsson, Gudmundur Ingi; Gigante, Bruna; Goodarzi, Mark O; Grallert, Harald; Gravito, Martha L; Groves, Christopher J; Hallmans, Göran; Hartikainen, Anna-Liisa; Hayward, Caroline; Hernandez, Dena; Hicks, Andrew A; Holm, Hilma; Hung, Yi-Jen; Illig, Thomas; Jones, Michelle R; Kaleebu, Pontiano; Kastelein, John J P; Khaw, Kay-Tee; Kim, Eric; Klopp, Norman; Komulainen, Pirjo; Kumari, Meena; Langenberg, Claudia; Lehtimäki, Terho; Lin, Shih-Yi; Lindström, Jaana; Loos, Ruth J F; Mach, François; McArdle, Wendy L; Meisinger, Christa; Mitchell, Braxton D; Müller, Gabrielle; Nagaraja, Ramaiah; Narisu, Narisu; Nieminen, Tuomo V M; Nsubuga, Rebecca N; Olafsson, Isleifur; Ong, Ken K; Palotie, Aarno; Papamarkou, Theodore; Pomilla, Cristina; Pouta, Anneli; Rader, Daniel J; Reilly, Muredach P; Ridker, Paul M; Rivadeneira, Fernando; Rudan, Igor; Ruokonen, Aimo; Samani, Nilesh; Scharnagl, Hubert; Seeley, Janet; Silander, Kaisa; Stančáková, Alena; Stirrups, Kathleen; Swift, Amy J; Tiret, Laurence; Uitterlinden, Andre G; van Pelt, L Joost; Vedantam, Sailaja; Wainwright, Nicholas; Wijmenga, Cisca; Wild, Sarah H; Willemsen, Gonneke; Wilsgaard, Tom; Wilson, James F; Young, Elizabeth H; Zhao, Jing Hua; Adair, Linda S; Arveiler, Dominique; Assimes, Themistocles L; Bandinelli, Stefania; Bennett, Franklyn; Bochud, Murielle; Boehm, Bernhard O; Boomsma, Dorret I; Borecki, Ingrid B; Bornstein, Stefan R; Bovet, Pascal; Burnier, Michel; Campbell, Harry; Chakravarti, Aravinda; Chambers, John C; Chen, Yii-Der Ida; Collins, Francis S; Cooper, Richard S; Danesh, John; Dedoussis, George; de Faire, Ulf; Feranil, Alan B; Ferrières, Jean; Ferrucci, Luigi; Freimer, Nelson B; Gieger, Christian; Groop, Leif C; Gudnason, Vilmundur; Gyllensten, Ulf; Hamsten, Anders; Harris, Tamara B; Hingorani, Aroon; Hirschhorn, Joel N; Hofman, Albert; Hovingh, G Kees; Hsiung, Chao Agnes; Humphries, Steve E; Hunt, Steven C; Hveem, Kristian; Iribarren, Carlos; Järvelin, Marjo-Riitta; Jula, Antti; Kähönen, Mika; Kaprio, Jaakko; Kesäniemi, Antero; Kivimaki, Mika; Kooner, Jaspal S; Koudstaal, Peter J; Krauss, Ronald M; Kuh, Diana; Kuusisto, Johanna; Kyvik, Kirsten O; Laakso, Markku; Lakka, Timo A; Lind, Lars; Lindgren, Cecilia M; Martin, Nicholas G; März, Winfried; McCarthy, Mark I; McKenzie, Colin A; Meneton, Pierre; Metspalu, Andres; Moilanen, Leena; Morris, Andrew D; Munroe, Patricia B; Njølstad, Inger; Pedersen, Nancy L; Power, Chris; Pramstaller, Peter P; Price, Jackie F; Psaty, Bruce M; Quertermous, Thomas; Rauramaa, Rainer; Saleheen, Danish; Salomaa, Veikko; Sanghera, Dharambir K; Saramies, Jouko; Schwarz, Peter E H; Sheu, Wayne H-H; Shuldiner, Alan R; Siegbahn, Agneta; Spector, Tim D; Stefansson, Kari; Strachan, David P; Tayo, Bamidele O; Tremoli, Elena; Tuomilehto, Jaakko; Uusitupa, Matti; van Duijn, Cornelia M; Vollenweider, Peter; Wallentin, Lars; Wareham, Nicholas J; Whitfield, John B; Wolffenbuttel, Bruce H R; Altshuler, David; Ordovas, Jose M; Boerwinkle, Eric; Palmer, Colin N A; Thorsteinsdottir, Unnur; Chasman, Daniel I; Rotter, Jerome I; Franks, Paul W; Ripatti, Samuli; Cupples, L Adrienne; Sandhu, Manjinder S; Rich, Stephen S; Boehnke, Michael; Deloukas, Panos; Mohlke, Karen L; Ingelsson, Erik; Abecasis, Goncalo R; Daly, Mark J; Neale, Benjamin M; Kathiresan, Sekar

2013-11-01

Triglycerides are transported in plasma by specific triglyceride-rich lipoproteins; in epidemiological studies, increased triglyceride levels correlate with higher risk for coronary artery disease (CAD). However, it is unclear whether this association reflects causal processes. We used 185 common variants recently mapped for plasma lipids (P triglycerides in risk for CAD. First, we highlight loci associated with both low-density lipoprotein cholesterol (LDL-C) and triglyceride levels, and we show that the direction and magnitude of the associations with both traits are factors in determining CAD risk. Second, we consider loci with only a strong association with triglycerides and show that these loci are also associated with CAD. Finally, in a model accounting for effects on LDL-C and/or high-density lipoprotein cholesterol (HDL-C) levels, the strength of a polymorphism's effect on triglyceride levels is correlated with the magnitude of its effect on CAD risk. These results suggest that triglyceride-rich lipoproteins causally influence risk for CAD.

Exposure to automotive pollution increases plasma susceptibility to oxidation.

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Sharman, James E; Coombes, Jeff S; Geraghty, Dominic P; Fraser, David I

2002-01-01

Low-density lipoprotein oxidation is implicated in the development of atherosclerosis. Plasma susceptibility to oxidation may be used as a marker of low-density lipoprotein oxidation and thus predict atherosclerotic risk. In this study the authors investigated the relationship between plasma susceptibility to oxidation and exposure to automotive pollution in a group of automobile mechanics (n = 16) exposed to high levels of automotive pollution, vs. matched controls (n = 13). The authors induced plasma oxidation by a free radical initiator and they determined susceptibility to oxidation by (1) change in absorbance at 234 nm, (2) lag time to conjugated diene formation, and (3) linear slope of the oxidation curve. Mechanics had significantly higher values (mean +/- standard error) for change in absorbance (1.60 +/- 0.05 vs. 1.36 +/- 0.05; p automotive pollutants increases plasma susceptibility to oxidation and may, in the long-term, increase the risk of developing atherosclerosis.

A clustering analysis of lipoprotein diameters in the metabolic syndrome

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Frazier-Wood Alexis C

2011-12-01

Full Text Available Abstract Background The presence of smaller low-density lipoproteins (LDL has been associated with atherosclerosis risk, and the insulin resistance (IR underlying the metabolic syndrome (MetS. In addition, some research has supported the association of very low-, low- and high-density lipoprotein (VLDL HDL particle diameters with components of the metabolic syndrome (MetS, although this has been the focus of less research. We aimed to explore the relationship of VLDL, LDL and HDL diameters to MetS and its features, and by clustering individuals by their diameters of VLDL, LDL and HDL particles, to capture information across all three fractions of lipoprotein into a unified phenotype. Methods We used nuclear magnetic resonance spectroscopy measurements on fasting plasma samples from a general population sample of 1,036 adults (mean ± SD, 48.8 ± 16.2 y of age. Using latent class analysis, the sample was grouped by the diameter of their fasting lipoproteins, and mixed effects models tested whether the distribution of MetS components varied across the groups. Results Eight discrete groups were identified. Two groups (N = 251 were enriched with individuals meeting criteria for the MetS, and were characterized by the smallest LDL/HDL diameters. One of those two groups, one was additionally distinguished by large VLDL, and had significantly higher blood pressure, fasting glucose, triglycerides, and waist circumference (WC; P Conclusions While small LDL diameters remain associated with IR and the MetS, the occurrence of these in conjunction with a shift to overall larger VLDL diameter may identify those with the highest fasting glucose, TG and WC within the MetS. If replicated, the association of this phenotype with more severe IR-features indicated that it may contribute to identifying of those most at risk for incident type II diabetes and cardiometabolic disease.

Effects of aerobic exercise on lipids and lipoproteins.

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Wang, Yating; Xu, Danyan

2017-07-05

Dyslipidemia is the risk of cardiovascular disease, and their relationship is clear. Lowering serum cholesterol can reduce the risk of coronary heart disease. At present, the main treatment is taking medicine, however, drug treatment has its limitations. Exercise not only has a positive effect on individuals with dyslipidemia, but can also help improve lipids profile. This review is intending to provide information on the effects of exercise training on both tranditional lipids, for example, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides and new lipids and lipoproteins such as non-high-density lipoprotein cholesterol, and postprandial lipoprotein. The mechanisms of aerobic exercise on lipids and lipoproteins are also briefly described.

Dairy products and plasma cholesterol levels

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Lena Ohlsson

2010-08-01

Full Text Available Cholesterol synthesized in the body or ingested is an essential lipid component for human survival from our earliest life. Newborns ingest about 3–4 times the amount per body weight through mother's milk compared to the dietary intake of adults. A birth level of 1.7 mmol/L plasma total cholesterol will increase to 4–4.5 mmol/L during the nursing period and continue to increase from adulthood around 40% throughout life. Coronary artery disease and other metabolic disorders are strongly associated with low-density lipoprotein (LDL and high-density lipoprotein (HDL cholesterol as well as triacylglycerol concentration. Milk fat contains a broad range of fatty acids and some have a negative impact on the cholesterol rich lipoproteins. The saturated fatty acids (SFAs, such as palmitic acid (C16:0, myristic acid (C14:0, and lauric acid (C12:0, increase total plasma cholesterol, especially LDL, and constitute 11.3 g/L of bovine milk, which is 44.8% of total fatty acid in milk fat. Replacement of dairy SFA and trans-fatty acids with polyunsaturated fatty acids decreases plasma cholesterol, especially LDL cholesterol, and is associated with a reduced risk of cardiovascular disease. Available data shows different effects on lipoproteins for different dairy products and there is uncertainty as to the impact a reasonable intake amount of dairy items has on cardiovascular risk. The aim of this review is to elucidate the effect of milk components and dairy products on total cholesterol, LDL, HDL, and the LDL/HDL quotients. Based on eight recent randomized controlled trials of parallel or cross-over design and recent reviews it can be concluded that replacement of saturated fat mainly (but not exclusively derived from high-fat dairy products with low-fat dairy products lowers LDL/HDL cholesterol and total/HDL cholesterol ratios. Whey, dairy fractions enriched in polar lipids, and techniques such as fermentation, or fortification of cows feeding can be used

Lipoprotein receptors in copper-deficient rats: in vitro binding of high-density lipoprotein subfractions to liver membranes

International Nuclear Information System (INIS)

Hassel, C.A.

1986-01-01

Three studies were conducted to determine whether the elevated plasma and HDL cholesterol levels observed in copper-deficient rats could be explained by the interaction of 125 I-HDL subfractions with liver membrane preparations in vitro. Rats from all studies were randomly divided into two dietary treatments, copper-deficient and adequate (0.7 mg and 8.0 mg Cukg diet, respectively). Total binding data and computer derived estimates (K/sub d/ and B/sub max/) were used to compare differences between treatments. Binding data from all experiments conformed to a one-site model. In all cases, binding was saturable and EDTA and pronase insensitive. Treatment differences were observed in Study I ( 125 I-apo E-free HDL binding to crude liver membranes). Significantly lower total binding and B/sub max/ were observed when lipoproteins and membranes from copper-deficient animals were used in the assay. Competition experiments from Studies II and III demonstrate that the different HDL subfractions competed effectively with one another for binding sites, indicating that apo E is not a determinant in binding of rat 125 I-HDL subfractions to purified liver plasma membranes

The effect of dietary fatty acid composition on the hepatic fatty acid content and plasma lipid profile in rats

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Tomáš Komprda

2015-01-01

Full Text Available The objective of the present study was to evaluate in a model organism the effect of different dietary lipids on plasma concentration of total cholesterol (TC, high-density lipoprotein cholesterol (HDL-C, low-density lipoprotein cholesterol (LDL-C and triacylglycerols (TAG. One hundred adult male rats (Wistar Albino were divided into 10 groups with 10 animals each and fed for 7 weeks either basic feed mixture (control diet, C or basic feed mixture with 5% of palm oil (P, safflower oil (SF, salmon oil (S, fish oil (F, Schizochytrium microalga oil (A, and 20% of beef tallow (T; four groups, respectively. The T-groups were fed for another 7 weeks T-, SF-, F- and A-diet, respectively. At the end of both the first and the second 7-week fattening period, plasma lipid concentration and hepatic fatty acid content was determined. Both A and F diets fed for 7 weeks decreased (P -1 compared to control (1.19 mmol∙l-1. The highest (P -1. A-diet had the most positive (decreasing effect on TAG concentrations (0.68–0.86 mmol∙l-1 compared to 1.22 and 2.88 mmol∙l-1 found in the C and T diets, respectively; P P Schizochytrium microalga oil (with high DHA content may have the potential for decreasing the risk of cardiovascular diseases.

Effects of dietary phospholipid level in cobia (Rachycentron canadum) larvae: growth, survival, plasma lipids and enzymes of lipid metabolism.

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Niu, J; Liu, Y J; Tian, L X; Mai, K S; Yang, H J; Ye, C X; Zhu, Y

2008-03-01

A study was conducted to determine the effects of dietary phospholipid (PL) levels in cobia (Rachycentron canadum) larvae with regard to growth, survival, plasma lipids and enzymes of lipid metabolism. Fish with an average weight of 0.4 g were fed diets containing four levels of PL (0, 20, 40 and 80 g kg(-1)dry matter: purity 97%) for 42 days. Final body weight (FBW), weight gain (WG) and survival ratio were highest in the 8% PL diet group and mortality was highest in PL-free diet group. We examined the activities of lipoprotein lipase (LPL) and hepatic lipase (HL) in liver, lecithin-cholesterolacyltransferase (LCAT) in plasma as well as plasma lipids and lipoprotein. LCAT activity showed a decrease of more than two-fold in PL-supplemented diet groups compared with the PL-free diet group. HL activity was highest in the 8% PL diet group and the other three groups showed no difference. LPL activity was significantly higher in the PL-supplemented diet groups than in the PL-free diet group. The dietary intervention significantly increased plasma phospholipids and total cholesterol (TC) levels, and the higher free cholesterol (FC) level contributed to the TC level. However, the fish fed PL exhibited a significantly decreased plasma triglyceride (TG) level. The lipoprotein fractions were also affected significantly by the PL. The PL-supplemented diet groups had significantly higher high-density lipoprotein (HDL) compared with the PL-free diet group, but showed a marked decrease in very low-density lipoprotein (VLDL). The results suggested that PL could modify plasma lipoprotein metabolism and lipid profile, and that the optimal dietary PL level may well exceed 80 g kg(-1) for cobia larvae according to growth and survival.

Novel function of lecithin-cholesterol acyltransferase. Hydrolysis of oxidized polar phospholipids generated during lipoprotein oxidation.

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Goyal, J; Wang, K; Liu, M; Subbaiah, P V

1997-06-27

Although the major function of lecithin-cholesterol acyltransferase (LCAT) is cholesterol esterification, our previous studies showed that it can also hydrolyze platelet-activating factor (PAF). Because of the structural similarities between PAF and the truncated phosphatidylcholines (polar PCs) generated during lipoprotein oxidation, we investigated the possibility that LCAT may also hydrolyze polar PCs to lyso-PC during the oxidation of plasma. PAF acetylhydrolase (PAF-AH), which is known to hydrolyze polar PCs in human plasma, was completely inhibited by 0.2 mM p-aminoethyl benzenesulfonyl fluoride (Pefabloc), a new serine esterase inhibitor, which had no effect on LCAT at this concentration. On the other hand, 1 mM diisopropylfluorophosphate (DFP) completely inhibited LCAT but had no effect on PAF-AH. Polar PC accumulation during the oxidation of plasma increased by 44% in the presence of 0.2 mM Pefabloc and by 30% in the presence of 1 mM DFP. The formation of lyso-PC was concomitantly inhibited by both of the inhibitors. The combination of the two inhibitors resulted in the maximum accumulation of polar PCs, suggesting that both PAF-AH and LCAT are involved in their breakdown. Oxidation of chicken plasma, which has no PAF-AH activity, also resulted in the formation of lyso-PC from the hydrolysis of polar PC, which was inhibited by DFP. Polar PCs, either isolated from oxidized plasma or by oxidation of labeled synthetic PCs, were hydrolyzed by purified LCAT, which had no detectable PAF-AH activity. These results demonstrate a novel function for LCAT in the detoxification of polar PCs generated during lipoprotein oxidation, especially when the PAF-AH is absent or inactivated.

Dentin surface treatment using a non-thermal argon plasma brush for interfacial bonding improvement in composite restoration

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Ritts, Andy Charles; Li, Hao; Yu, Qingsong; Xu, Changqi; Yao, Xiaomei; Hong, Liang; Wang, Yong

2010-01-01

The objective of this study is to investigate the treatment effects of non-thermal atmospheric gas plasmas on dentin surfaces for composite restoration. Extracted unerupted human third molars were used by removing the crowns and etching the exposed dentin surfaces with 35% phosphoric acid gel. The dentin surfaces were treated by using a non-thermal atmospheric argon plasma brush for various durations. The molecular changes of the dentin surfaces were analyzed using FTIR/ATR and an increase in carbonyl groups on dentin surfaces was detected with plasma treated dentin. Adper Single Bond Plus adhesive and Filtek Z250 dental composite were applied as directed. To evaluate the dentin/composite interfacial bonding, the teeth thus prepared were sectioned into micro-bars as the specimens for tensile test. Student Newman Keuls tests showed that the bonding strength of the composite restoration to peripheral dentin was significantly increased (by 64%) after 30 s plasma treatment. However, the bonding strength to plasma treated inner dentin did not show any improvement. It was found that plasma treatment of peripheral dentin surface up to 100 s gave an increase in interfacial bonding strength, while a prolong plasma treatment of dentin surfaces, e.g., 5 min treatments, showed a decrease in interfacial bonding strength. PMID:20831586

Air plasma spray processing and electrochemical characterization of SOFC composite cathodes

Science.gov (United States)

White, B. D.; Kesler, O.; Rose, Lars

Air plasma spraying has been used to produce porous composite cathodes containing (La 0.8Sr 0.2) 0.98MnO 3- y (LSM) and yttria-stabilized zirconia (YSZ) for use in solid oxide fuel cells (SOFCs). Preliminary investigations focused on determining the range of plasma conditions under which each of the individual materials could be successfully deposited. A range of conditions was thereby determined that was suitable for the deposition of a composite cathode from pre-mixed LSM and YSZ powders. A number of composite cathodes were produced using different combinations of parameter values within the identified range according to a Uniform Design experimental grid. Coatings were then characterized for composition and microstructure using EDX and SEM. As a result of these tests, combinations of input parameter values were identified that are best suited to the production of coatings with microstructures appropriate for use in SOFC composite cathodes. A selection of coatings representative of the types of observed microstructures were then subjected to electrochemical testing to evaluate the performance of these cathodes. From these tests, it was found that, in general, the coatings that appeared to have the most suitable microstructures also had the highest electrochemical performances, provided that the deposition efficiency of both phases was sufficiently high.

Air plasma spray processing and electrochemical characterization of SOFC composite cathodes

Energy Technology Data Exchange (ETDEWEB)

White, B.D. [Department of Mechanical Engineering, The University of British Columbia, 2054-6250 Applied Sciences Lane, Vancouver, British Columbia (Canada); Kesler, O. [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King' s College Road, Toronto, Ontario (Canada); Rose, Lars [Department of Materials Engineering, The University of British Columbia, 309-6350 Stores Road, Vancouver, British Columbia (Canada); National Research Council (Canada)

2008-03-15

Air plasma spraying has been used to produce porous composite cathodes containing (La{sub 0.8}Sr{sub 0.2}){sub 0.98}MnO{sub 3-y} (LSM) and yttria-stabilized zirconia (YSZ) for use in solid oxide fuel cells (SOFCs). Preliminary investigations focused on determining the range of plasma conditions under which each of the individual materials could be successfully deposited. A range of conditions was thereby determined that was suitable for the deposition of a composite cathode from pre-mixed LSM and YSZ powders. A number of composite cathodes were produced using different combinations of parameter values within the identified range according to a Uniform Design experimental grid. Coatings were then characterized for composition and microstructure using EDX and SEM. As a result of these tests, combinations of input parameter values were identified that are best suited to the production of coatings with microstructures appropriate for use in SOFC composite cathodes. A selection of coatings representative of the types of observed microstructures were then subjected to electrochemical testing to evaluate the performance of these cathodes. From these tests, it was found that, in general, the coatings that appeared to have the most suitable microstructures also had the highest electrochemical performances, provided that the deposition efficiency of both phases was sufficiently high. (author)

Lipoproteins as modulators of atherothrombosis: From endothelial function to primary and secondary coagulation.

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Ouweneel, Amber B; Van Eck, Miranda

2016-07-01

Atherothrombosis is a complication of atherosclerosis that causes acute cardiovascular events such as myocardial infarction and stroke. Circulating lipid levels are highly correlated with atherosclerotic plaque development. In addition, experimental evidence suggests that lipids also directly influence thrombosis and influence the risk and the outcome of acute cardiovascular events. Plasma lipoproteins influence three aspects important to atherothrombosis: endothelial function, platelet aggregation (primary coagulation) and secondary coagulation. Overall, VLDL, LDL and oxLDL promote thrombus formation, whereas HDL shows antithrombotic actions. In this review we will address the current knowledge about modulation of atherothrombosis by lipoproteins, summarizing findings from in vitro and in vivo animal studies, as well as from observational and interventional studies in humans. We will conclude with future perspectives for lipid modulation in the prevention of atherothrombosis. Copyright © 2015 Elsevier Inc. All rights reserved.

Cardiorespiratory fitness modifies the association between dietary fat intake and plasma fatty acids.

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König, D; Väisänen, S B; Bouchard, C; Halle, M; Lakka, T A; Baumstark, M W; Alen, M; Berg, A; Rauramaa, R

2003-07-01

To investigate the relation between (1) cardiorespiratory fitness and plasma saturated, monounsaturated and polyunsaturated fatty acids and (2) the interactions between cardiorespiratory fitness, dietary fat intake and plasma fatty acid composition. Cross-sectional analysis. The subjects were randomly selected, 127 middle-aged Finnish men participating in the DNASCO exercise intervention study. Cardiorespiratory fitness was determined spiroergometrically, dietary intake of macro- and micronutrients by 4-day food records and plasma fatty acids by gas chromatography. The subjects were divided into tertiles of aerobic fitness. Differences between fitness tertiles were not observed for dietary intake of total fat, and saturated, monounsaturated or polyunsaturated fatty acids (percent of total energy). In contrast, plasma saturated fatty acids were significantly lower (P cardiorespiratory fitness are associated with different levels in plasma saturated and polyunsaturated fatty acids and lead to modifications in the association between dietary and plasma fatty acids. These findings can perhaps be explained by a reduced hepatic fatty acid and lipoprotein synthesis as well as by an enhanced muscular lipid utilization, which are commonly seen in those who are physically active and who exhibit a higher level of fitness.

Graphene-reinforced aluminum matrix composites prepared by spark plasma sintering

Institute of Scientific and Technical Information of China (English)

Wen-ming Tian; Song-mei Li; Bo Wang; Xin Chen; Jian-hua Liu; Mei Yu

2016-01-01

Graphene-reinforced 7055 aluminum alloy composites with different contents of graphene were prepared by spark plasma sinter-ing (SPS). The structure and mechanical properties of the composites were investigated. Testing results show that the hardness, compressive strength, and yield strength of the composites are improved with the addition of 1wt% graphene. A clean, strong interface is formed between the metal matrix and graphene via metallurgical bonding on atomic scale. Harmful aluminum carbide (Al4C3) is not formed during SPS processing. Further addition of graphene (above 1wt%) results in the deterioration in mechanical properties of the composites. The agglomeration of graphene plates is exacerbated with increasing graphene content, which is the main reason for this deterioration.

Quantitative assessment of lipoprotein metabolism by positron emission tomography with an 18F-containing residualizing label

International Nuclear Information System (INIS)

Daugherty, A.; Sobel, B.; Kilbourn, M.R.; Dence, C.S.; Thorpe, S.R.

1992-01-01

Residualizing labels for proteins are designed to remain entrapped within cells following uptake and degradation of the carrier protein. In the present work we report the synthesis of a novel residualizing label, N-lactitol-S-([ 18 F]fluorophenacyl)-cysteamine ([ 18 F]LCSH), and its use for quantifying the accumulation of low density lipoprotein in tissues in vivo by positron emission tomography (PET). The retention of degradation products in tissues from lipoprotein or from other rapidly catabolized protein pharmaceuticals tagged with [ 18 F]LCSH reduces leakage of tracer into the plasma compartment. Thus, residualizing labels provide a valuable tool for enhancing signal-to-noise ratios, even during the relatively short interval of PET studies. (author)

Lipoprotein (a): relation to other risk factors and genetic heritability; results from a Dutch parent-twin study

NARCIS (Netherlands)

Boomsma, D.I.; Kaptein, A; Kempen, H.J.; Gevers Leuven, J.A.; Princen, H.M.

1993-01-01

We measured plasma levels of lipoprotein(a) (Lp(a)) in a sample of 152 Dutch adolescent mono- and dizygotic twin pairs and their parents. The distribution of Lp(a) levels was skewed, with the highest frequencies at low levels and was similar for adult men and women and their children. The

Lipoprotein particle distribution and skeletal muscle lipoprotein lipase activity after acute exercise.

Science.gov (United States)

Harrison, Michael; Moyna, Niall M; Zderic, Theodore W; O'Gorman, Donal J; McCaffrey, Noel; Carson, Brian P; Hamilton, Marc T

2012-07-10

Many of the metabolic effects of exercise are due to the most recent exercise session. With recent advances in nuclear magnetic resonance spectroscopy (NMRS), it is possible to gain insight about which lipoprotein particles are responsible for mediating exercise effects. Using a randomized cross-over design, very low density lipoprotein (VLDL) responses were evaluated in eight men on the morning after i) an inactive control trial (CON), ii) exercising vigorously on the prior evening for 100 min followed by fasting overnight to maintain an energy and carbohydrate deficit (EX-DEF), and iii) after the same exercise session followed by carbohydrate intake to restore muscle glycogen and carbohydrate balance (EX-BAL). The intermediate, low and high density lipoprotein particle concentrations did not differ between trials. Fasting triglyceride (TG) determined biochemically, and mean VLDL size were lower in EX-DEF but not in EX-BAL compared to CON, primarily due to a reduction in VLDL-TG in the 70-120 nm (large) particle range. In contrast, VLDL-TG was lower in both EX-DEF and EX-BAL compared to CON in the 43-55 nm (medium) particle range. VLDL-TG in smaller particles (29-43 nm) was unaffected by exercise. Because the majority of VLDL particles were in this smallest size range and resistant to change, total VLDL particle concentration was not different between any of these conditions. Skeletal muscle lipoprotein lipase (LPL) activity was also not different across these 3 trials. However, in CON only, the inter-individual differences in LPL activity were inversely correlated with fasting TG, VLDL-TG, total, large and small VLDL particle concentration and VLDL size, indicating a regulatory role for LPL in the non-exercised state. These findings reveal a high level of differential regulation between different sized triglyceride-rich lipoproteins following exercise and feeding, in the absence of changes in LPL activity.

Interaction of Mycoplasma hominis PG21 with Human Dendritic Cells: Interleukin-23-Inducing Mycoplasmal Lipoproteins and Inflammasome Activation of the Cell.

Science.gov (United States)

Goret, J; Béven, L; Faustin, B; Contin-Bordes, C; Le Roy, C; Claverol, S; Renaudin, H; Bébéar, C; Pereyre, S

2017-08-01

Mycoplasma hominis lacks a cell wall, and lipoproteins anchored to the extracellular side of the plasma membrane are in direct contact with the host components. A Triton X-114 extract of M. hominis enriched with lipoproteins was shown to stimulate the production of interleukin-23 (IL-23) by human dendritic cells (hDCs). The inflammasome activation of the host cell has never been reported upon M. hominis infection. We studied here the interaction between M. hominis PG21 and hDCs by analyzing both the inflammation-inducing mycoplasmal lipoproteins and the inflammasome activation of the host cell. IL-23-inducing lipoproteins were determined using a sequential extraction strategy with two nondenaturing detergents, Sarkosyl and Triton X-114, followed by SDS-PAGE separation and mass spectrometry identification. The activation of the hDC inflammasome was assessed using PCR array and enzyme-linked immunosorbent assay (ELISA). We defined a list of 24 lipoproteins that could induce the secretion of IL-23 by hDCs, 5 with a molecular mass between 20 and 35 kDa and 19 with a molecular mass between 40 and 100 kDa. Among them, lipoprotein MHO_4720 was identified as potentially bioactive, and a synthetic lipopeptide corresponding to the N-terminal part of the lipoprotein was subsequently shown to induce IL-23 release by hDCs. Regarding the hDC innate immune response, inflammasome activation with caspase-dependent production of IL-1β was observed. After 24 h of coincubation of hDCs with M. homini s, downregulation of the NLRP3-encoding gene and of the adaptor PYCARD-encoding gene was noticed. Overall, this study provides insight into both protagonists of the interaction of M. hominis and hDCs. IMPORTANCE Mycoplasma hominis is a human urogenital pathogen involved in gynecologic and opportunistic infections. M. hominis lacks a cell wall, and its membrane contains many lipoproteins that are anchored to the extracellular side of the plasma membrane. In the present study, we focused on

Determination of plasminogen/plasmin system components and indicators of lipoproteins oxidative modification under arterial hypertension

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O. I. Yusova

2018-02-01

Full Text Available The present study was investigated of levels of oxidative modification of lipoproteins and content of plasminogen/plasmin system components – tissue-type plasminogen activator (t-PA and plasminogen activators inhibitor-1 (PAI-I, in patients with stage II arterial hypertension (AHT and resistant form. It was established that t-PA level in blood plasma of the patients is 2 times lower under stage II hypertension than normal and 2.5 times lower under resistant AHT. The inhibitor activity is 1.5 and 2 times higher consequently. It is concluded that patients with AHT have a decreased fibrinolytic potential, which can cause thrombotic states. Our evaluation showed a significant accumulation of products of lipid and protein oxidation, decrease of activity of antioxidant enzymes and changes of the activity of high density-lipoproteins-associated enzymes (decrease of paraoxonase-1 activity, increase of myeloperoxidase activity. Oxidized lipoproteins, t-PA and PAI-1 can be used as prognostic markers of development of complications and for evaluating the efficacy of therapy in patients with arterial hypertension.

Blood Lipoproteins under the Action of Exogenous Sex Steroids in the Postresuscitation Period

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L. N. Shcherbakova

2011-01-01

Full Text Available Objective: to study the effect of reproductive hormones on the blood lipoprotein spectrum in the postresuscitation period after cardiac arrest. Materials and methods. Experiments were carried out on 66 mature albino rats of either sex weighing 200—250 g. Ten-minute cardiac arrest was induced by intrathoracic ligation of the vascular bundle. At 30 min after resuscitation, 49 animals were intramuscularly injected placebo and 17 animals were administered gyn-odian depot (Schering, Germany. The investigators measured the plasma concentrations of progesterone, 17-OH progesterone, androstenedione, dehydroepiandrosterone sulfate, testosterone, estradiol, and estriol, as well as the levels of triglycerides, total, and high-density lipoprotein (HDL, low-density lipoprotein (LDL, and very low-density lipoprotein (VLDL cholesterols. Blood was sampled on days 2 and 16 in the absence of therapy and on day 16 of sex steroid therapy. Results. By day 2 postresuscitation, the progesterone/estradiol ratio increased by approximately 1.8 times in males and females. Despite the fact that there were no changes in the concentrations of triglycerides, VLDL and HDL cholesterols in both males and females at that time, but the level of LDL cholesterol increased. Gender-related differences in the LDL spectrum by day 2 postresuscitation remained only in the levels of LDL cholesterol. Despite the normalization of progesterone levels, the concentrations of triglycerides and VLDL cholesterol decreased by day 16 of the postresuscitative period in the absence of therapy. There were no gender-related differences in the lipoprotein spectrum at this stage. The exogenous estradiol in combination with dehydroepiandrosterone caused a significant increase in the concentration of HLD cholesterol and a reduction in that of VLDL cholesterol in males and females both. Conclusion. Under gynodian action, the lipid spectrum was indicative of the exogenous estra-diol and

Plasma Methods of Obtainment of Multifunctional Composite Materials, Dispersion-Hardened by Nanoparticles

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Sizonenko, O. N.; Grigoryev, E. G.; Pristash, N. S.; Zaichenko, A. D.; Torpakov, A. S.; Lypian, Ye. V.; Tregub, V. A.; Zholnin, A. G.; Yudin, A. V.; Kovalenko, A. A.

2017-09-01

High voltage electric discharge (HVED) in disperse system "hydrocarbon liquid - powder" due to impact of plasma discharge channel, electromagnetic fields, shock waves mechanical impact, hydro flows and volume microcavitation leads to synthesis of nanocarbon, metal powders dispersion and synthesis of micro- (from 10-6 to 10-7 m) and nanosized (from 10-7 to 10-9 m) composite powders of hardening phases. Spark plasma sintering (SPS) of powder mixtures allows targeted control of grain growth rate and thus allows obtainment of multifunctional composite materials dispersion hardened by nanoparticles. Processes of HVED synthesis of micro- and nanosized powders of new compositions from elemental metal powders and their mixtures with the subsequent application of high-speed SPS of obtained powders create conditions for increase of strength (by 10-20 %), hardness and wear-resistance (by 30-60 %) of obtained materials.

Aminoacylation of the N-terminal cysteine is essential for Lol-dependent release of lipoproteins from membranes but does not depend on lipoprotein sorting signals.

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Fukuda, Ayumu; Matsuyama, Shin-Ichi; Hara, Takashi; Nakayama, Jiro; Nagasawa, Hiromichi; Tokuda, Hajime

2002-11-08

Lipoproteins are present in a wide variety of bacteria and are anchored to membranes through lipids attached to the N-terminal cysteine. The Lol system of Escherichia coli mediates the membrane-specific localization of lipoproteins. Aspartate at position 2 functions as a Lol avoidance signal and causes the retention of lipoproteins in the inner membrane, whereas lipoproteins having residues other than aspartate at position 2 are released from the inner membrane and localized to the outer membrane by the Lol system. Phospholipid:apolipoprotein transacylase, Lnt, catalyzes the last step of lipoprotein modification, converting apolipoprotein into mature lipoprotein. To reveal the importance of this aminoacylation for the Lol-dependent membrane localization, apolipoproteins were prepared by inhibiting lipoprotein maturation. Lnt was also purified and used to convert apolipoprotein into mature lipoprotein in vitro. The release of these lipoproteins was examined in proteoliposomes. We show here that the aminoacylation is essential for the Lol-dependent release of lipoproteins from membranes. Furthermore, lipoproteins with aspartate at position 2 were found to be aminoacylated both in vivo and in vitro, indicating that the lipoprotein-sorting signal does not affect lipid modification.

Phenolic extract from Ocimum basilicum restores lipid metabolism in Triton WR-1339-induced hyperlipidemic mice and prevents lipoprotein-rich plasma oxidation

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Ilham Touiss

2017-03-01

Full Text Available In this study we investigated the hypolipidemic and anti-lipoprotein-oxidation activities of phenolic extract from sweet basil a popular culinary herb. The hypolipidemic activity was studied in mice model injected intraperitoneally with Triton WR-1339 at a dose of 200 mg/kg body weight. The animals were grouped as follows: normolipidemic control group (n = 8, hyperlipidemic control group (n = 8 and phenolic extract-treated group (n = 8 at a dose of 200 mg/kg body weight. After 7 h and 24 h treatment, the oral administration of the phenolic extract exerts a significant reduction of plasma total cholesterol, triglycerides and LDL-cholesterol concentrations (P < 0.001. On the other hand, we demonstrated that the phenolic extract prevents plasma lipid oxidation by 16% (P < 0.001, 20% (P < 0.001, 32% (P < 0.001 and 44% (P < 0.001 at a doses of 10, 25, 50 and 100 μg/mL, respectively. The results were compared with ascorbic acid used as standard synthetic antioxidant. HPLC analysis shows that the extract contains 4 major phenolics and is especially rich in rosmarinic acid. This finding indicates that the phenolic extract might be beneficial in lowering hyperlipidemia and preventing atherosclerosis.

Association of polymorphisms in genes involved in lipoprotein metabolism with plasma concentrations of remnant lipoproteins and HDL subpopulations before and after hormone therapy in postmenopausal women

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Diabetes mellitus is a major risk factor for coronary heart disease (CHD), renal failure, retinopathy, and neuropathy. Lowering glycosylated hemoglobin (HbA1c) as well as low-density lipoprotein-cholesterol (LDL-C) has been associated with a decreased risk of these complications. We evaluated the ut...

Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

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Zhang, Huanxia, E-mail: zhanghuanxia818@163.com [College of Materials and Textile Engineering, Jiaxing University, Jiaxing 314001, Zhejiang (China); Li, Wei [College of Textile Engineering, Donghua University, Shanghai 201620 (China); Key Laboratory of Textile Science and Technology, Ministry of Education, Shanghai 201620 (China)

2015-11-30

Graphical abstract: - Highlights: • A simple method to improve surface properties is applied to carbon fibers. • The maleic anhydride was grafted onto the carbon fiber with the FTIR spectra. • The plasma treatment time and polymerization condition affected on the grafting rate. • The carbon fibers exhibited excellent surface hydrophilicity and IFSS properties. - Abstract: Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid–base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as C−O, C=O, and O−C=O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the

Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

International Nuclear Information System (INIS)

Zhang, Huanxia; Li, Wei

2015-01-01

Graphical abstract: - Highlights: • A simple method to improve surface properties is applied to carbon fibers. • The maleic anhydride was grafted onto the carbon fiber with the FTIR spectra. • The plasma treatment time and polymerization condition affected on the grafting rate. • The carbon fibers exhibited excellent surface hydrophilicity and IFSS properties. - Abstract: Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid–base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as C−O, C=O, and O−C=O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the

A More Flexible Lipoprotein Sorting Pathway

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Chahales, Peter

2015-01-01

Lipoprotein biogenesis in Gram-negative bacteria occurs by a conserved pathway, each step of which is considered essential. In contrast to this model, LoVullo and colleagues demonstrate that the N-acyl transferase Lnt is not required in Francisella tularensis or Neisseria gonorrhoeae. This suggests the existence of a more flexible lipoprotein pathway, likely due to a modified Lol transporter complex, and raises the possibility that pathogens may regulate lipoprotein processing to modulate interactions with the host. PMID:25755190

Analyzing the molecular mechanism of lipoprotein localization in Brucella.

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Goolab, Shivani; Roth, Robyn L; van Heerden, Henriette; Crampton, Michael C

2015-01-01

Bacterial lipoproteins possess diverse structure and functionality, ranging from bacterial physiology to pathogenic processes. As such many lipoproteins, originating from Brucella are exploited as potential vaccines to countermeasure brucellosis infection in the host. These membrane proteins are translocated from the cytoplasm to the cell membrane where they are anchored peripherally by a multifaceted targeting mechanism. Although much research has focused on the identification and classification of Brucella lipoproteins and their potential use as vaccine candidates for the treatment of Brucellosis, the underlying route for the translocation of these lipoproteins to the outer surface of the Brucella (and other pathogens) outer membrane (OM) remains mostly unknown. This is partly due to the complexity of the organism and evasive tactics used to escape the host immune system, the variation in biological structure and activity of lipoproteins, combined with the complex nature of the translocation machinery. The biosynthetic pathway of Brucella lipoproteins involves a distinct secretion system aiding translocation from the cytoplasm, where they are modified by lipidation, sorted by the lipoprotein localization machinery pathway and thereafter equipped for export to the OM. Surface localized lipoproteins in Brucella may employ a lipoprotein flippase or the β-barrel assembly complex for translocation. This review provides an overview of the characterized Brucella OM proteins that form part of the OM, including a handful of other characterized bacterial lipoproteins and their mechanisms of translocation. Lipoprotein localization pathways in gram negative bacteria will be used as a model to identify gaps in Brucella lipoprotein localization and infer a potential pathway. Of particular interest are the dual topology lipoproteins identified in Escherichia coli and Haemophilus influenza. The localization and topology of these lipoproteins from other gram negative bacteria

Analyzing the molecular mechanism of lipoprotein localization in Brucella

Science.gov (United States)

Goolab, Shivani; Roth, Robyn L.; van Heerden, Henriette; Crampton, Michael C.

2015-01-01

Bacterial lipoproteins possess diverse structure and functionality, ranging from bacterial physiology to pathogenic processes. As such many lipoproteins, originating from Brucella are exploited as potential vaccines to countermeasure brucellosis infection in the host. These membrane proteins are translocated from the cytoplasm to the cell membrane where they are anchored peripherally by a multifaceted targeting mechanism. Although much research has focused on the identification and classification of Brucella lipoproteins and their potential use as vaccine candidates for the treatment of Brucellosis, the underlying route for the translocation of these lipoproteins to the outer surface of the Brucella (and other pathogens) outer membrane (OM) remains mostly unknown. This is partly due to the complexity of the organism and evasive tactics used to escape the host immune system, the variation in biological structure and activity of lipoproteins, combined with the complex nature of the translocation machinery. The biosynthetic pathway of Brucella lipoproteins involves a distinct secretion system aiding translocation from the cytoplasm, where they are modified by lipidation, sorted by the lipoprotein localization machinery pathway and thereafter equipped for export to the OM. Surface localized lipoproteins in Brucella may employ a lipoprotein flippase or the β-barrel assembly complex for translocation. This review provides an overview of the characterized Brucella OM proteins that form part of the OM, including a handful of other characterized bacterial lipoproteins and their mechanisms of translocation. Lipoprotein localization pathways in gram negative bacteria will be used as a model to identify gaps in Brucella lipoprotein localization and infer a potential pathway. Of particular interest are the dual topology lipoproteins identified in Escherichia coli and Haemophilus influenza. The localization and topology of these lipoproteins from other gram negative bacteria

Distribution of fatty acids from dietary oils into phospholipid classes of triacylglycerol-rich lipoproteins in healthy subjects.

Science.gov (United States)

Abia, Rocio; Pacheco, Yolanda M; Montero, Emilio; Ruiz-Gutierrez, Valentina; Muriana, Francisco J G

2003-02-21

Several studies have suggested that lipoprotein metabolism can be affected by lipoprotein phospholipid composition. We investigated the effect of virgin olive oil (VOO) and high-oleic sunflower oil (HOSO) intake on the distribution of fatty acids in triacylglycerols (TG), cholesteryl esters (CE) and phospholipid (PL) classes of triacylglycerol-rich lipoproteins (TRL) from normolipidemic males throughout a 7 h postprandial metabolism. Particularly, changes in oleic acid (18:1n-9) concentration of PL were used as a marker of in vivo hydrolysis of TRL external monolayer. Both oils equally promoted the incorporation of oleic acid into the TG and CE of postprandial TRL. However, PL was enriched in oleic acid (18:1n-9) and n-3 polyunsaturated fatty acids (PUFA) after VOO meal, whereas in stearic (18:0) and linoleic (18:2n-6) acids after HOSO meal. We also found that VOO produced TRL which PL 18:1n-9 content was dramatically reduced along the postprandial period. We conclude that the fatty acid composition of PL can be a crucial determinant for the clearance of TRL during the postprandial metabolism of fats.

Characterization of phospholipid composition and its control in the plasma membrane of developing soybean root

International Nuclear Information System (INIS)

Whitman, C.E.

1985-01-01

The phospholipid composition of plasma membrane enriched fractions from developing soybean root and several mechanisms which may regulate it have been examined. Plasma membrane vesicles were isolated from meristematic and mature sections of four-day-old dark grown soybean roots (Glycine max [L.] Merr. Cult. Wells II). Analysis of lipid extracts revealed two major phospholipid classes: phosphatidylcholine and phosphatidylethanolamine. Minor phospholipid classes were phosphatidylinositol, phosphatidylserine, phosphatidylgylcerol and diphosphatidylgylcerol. Phospholipid composition was similar at each developmental stage. Fatty acids of phosphatidylcholine and phosphatidylethanolamine were 16:0, 18:0, 18:2, and 18:3. Fatty acid composition varied with both phospholipid class and the developmental stage of the root. The degradation of phosphatidylcholine by endogenous phospholipase D during membrane isolation indicated that this enzyme might be involved in phospholipid turnover within the membrane. Phospholipase D activity was heat labile and increasing the pH of the enzyme assay from 5.3 to 7.8 resulted in 90% inhibition of activity. The turnover of fatty acids within the phospholipids of the plasma membrane was studied. Mature root sections were incubated with [1- 14 C] acetate, 1 mM Na acetate and 50 μg/ml chloramphenicol. Membrane lipid extracts analyzed for phospholipid class and acyl chain composition revealed that the long incubation times did not alter the phospholipid composition of the plasma membrane enriched fraction