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Sample records for human apolipoprotein ai

  1. Opposite regulation of human versus mouse apolipoprotein A-I by fibrates in human apolipoprotein A-I transgenic mice.

    PubMed Central

    Berthou, L; Duverger, N; Emmanuel, F; Langouët, S; Auwerx, J; Guillouzo, A; Fruchart, J C; Rubin, E; Denèfle, P; Staels, B; Branellec, D

    1996-01-01

    The regulation of liver apolipoprotein (apo) A-I gene expression by fibrates was studied in human apo A-I transgenic mice containing a human genomic DNA fragment driving apo A-I expression in liver. Treatment with fenofibrate (0.5% wt/wt) for 7 d increased plasma human apo A-I levels up to 750% and HDL-cholesterol levels up to 200% with a shift to larger particles. The increase in human apo A-I plasma levels was time and dose dependent and was already evident after 3 d at the highest dose (0.5% wt/wt) of fenofibrate. In contrast, plasma mouse apo A-I concentration was decreased after fenofibrate in nontransgenic mice. The increase in plasma human apo A-I levels after fenofibrate treatment was associated with a 97% increase in hepatic human apo A-I mRNA, whereas mouse apo A-I mRNA levels decreased to 51%. In nontransgenic mice, a similar down-regulation of hepatic apo A-I mRNA levels was observed. Nuclear run-on experiments demonstrated that the increase in human apo A-I and the decrease in mouse apo A-I gene expression after fenofibrate occurred at the transcriptional level. Since part of the effects of fibrates are mediated through the nuclear receptor PPAR (peroxisome proliferator-activated receptor), the expression of the acyl CoA oxidase (ACO) gene was measured as a control of PPAR activation. Both in transgenic and nontransgenic mice, fenofibrate induced ACO mRNA levels up to sixfold. When transgenic mice were treated with gemfibrozil (0.5% wt/wt) plasma human apo A-I and HDL-cholesterol levels increased 32 and 73%, respectively, above control levels. The weaker effect of this compound on human apo A-I and HDL-cholesterol levels correlated with a less pronounced impact on ACO mRNA levels (a threefold increase) suggesting that the level of induction of human apo A-I gene is related to the PPAR activating potency of the fibrate used. Treatment of human primary hepatocytes with fenofibric acid (500 microM) provoked an 83 and 50% increase in apo A-I secretion and

  2. A complete backbone spectral assignment of human apolipoprotein AI on a 38 kDa preβHDL (Lp1-AI) particle

    SciTech Connect

    Ren, Xuefeng; Yang, Yunhuang; Neville, T.; Hoyt, David W.; Sparks, Daniel L.; Wang, Jianjun

    2007-06-12

    Apolipoprotein A-I (apoAI, 243-residues) is the major protein component of the high-density lipoprotein (HDL) that has been a hot subject of interests because of its anti-atherogenic properties. This important property of apoAI is related to its roles in reverse cholesterol transport pathway. Upon lipid-binding, apoAI undergoes conformational changes from lipid-free to several different HDL-associated states (1). These different conformational states regulate HDL formation, maturation and transportation. Two initial conformational states of apoAI are lipid-free apoAI and apoAI/preβHDL that recruit phospholipids and cholesterol to form HDL particles. In particular, lipid-free apoAI specifically binds to phospholipids to form lipid-poor apoAI, including apoAI/preβ-HDL (~37 kDa). As a unique class of lipid poor HDL, both in vitro and in vivo evidence demonstrates that apoAI/preβ-HDLs are the most effective acceptors specifically for free cholesterol in human plasma and serves as the precursor of HDL particles (2). Here we report a complete backbone spectral assignment of human apoAI/preβHDL. Secondary structure prediction using backbone NMR parameters indicates that apoAI/preβHDL displays a two-domain structure: the N-terminal four helix-bundle domain (residues 1-186) and the C-terminal flexible domain (residues 187-243). A structure of apoAI/preβ-HDL is the first lipid-associated structure of apoAI and is critical for us to understand how apoAI recruits cholesterol to initialize HDL formation. BMRB deposit with accession number: 15093.

  3. Properties of discoidal complexes of human apolipoprotein A-I with phosphatidylcholines containing various fatty acid chains.

    PubMed

    Zorich, N L; Kézdy, K E; Jonas, A

    1987-06-02

    In this study we demonstrate that apolipoprotein A-I determined the common size classes of discoidal particles formed with numerous phosphatidylcholines, and with ether analogs of phosphatidylcholines. We show furthermore, that the nature of the lipids dictates the distribution of particles among the different size classes. These experiments were performed with discoidal complexes containing various phospholipids (phosphatidylcholines with saturated and unsaturated fatty acid chains of different lengths and the ether analog of 1-palmitoyl-2-oleoylphosphatidylcholine), cholesterol, and human apolipoprotein A-I, prepared by the sodium cholate dialysis method, and fractionated by Bio-Gel A-5m gel-filtration chromatography. The complex preparations were analyzed in terms of their average composition, spectral properties of the apolipoprotein, and the dynamic behavior of the lipid domains. Nondenaturing gradient gel electrophoresis was used to analyze the size classes of particles present in the complex preparations. Starting with reaction mixtures containing around 100:1, phospholipid/apolipoprotein A-I molar ratios, complexes were isolated with molar ratios from 40:1 to 100:1. In most complexes apolipoprotein A-I had high levels of alpha-helical structure (65-77% alpha-helix), and tryptophan residues in a nonpolar environment. The lipid domains of complexes exhibited the dynamic behavior expected of the main phospholipid components. In the average size range from 90 to 100 A diameters, discrete particle classes with 80, 87, 102, 108, or 112 A Stokes diameters were observed for all the complexes containing different phospholipids. These discrete, recurring particle sizes are attributed to distinct apolipoprotein A-I conformations and variable lipid content.

  4. Radial-immunodiffusion assay of human apolipoprotein A-I with use of two monoclonal antibodies combined.

    PubMed

    Marcovina, S; Di Cola, G; Catapano, A L

    1986-12-01

    We produced and characterized several monoclonal antibodies directed toward human plasma apolipoprotein A-I. Two of them, A-I-12 and A-I-57, individually precipitated purified or native high-density lipoprotein in agarose gel by double immunodiffusion. Because radial immunodiffusion performed with a single monoclonal antibody gave faint and diffuse rings of precipitation, we developed and optimized working conditions for using these two monoclonal antibodies combined to determine apolipoprotein A-I in human plasma. This combination gave easy-to-measure, clear, sharp rings, and linear and parallel standard curves for HDL3 (the primary standard) and a reference serum (the secondary standard). Moreover, no pretreatment of samples with dissociating agents or detergents is necessary. The assay was complete after overnight incubation, as compared with two to three days when polyclonal antisera were used. Apolipoprotein A-I concentrations as measured in 128 normolipidemic subjects and in 72 patients with various lipid disorders by the radial immunodiffusion technique with monoclonal antibodies (x) compared well (r = 0.882; y = 1.029x-0.036) with those measured by radial immunodiffusion with polyclonal antisera (y).

  5. Nucleotide sequence and the encoded amino acids of human apolipoprotein A-I mRNA.

    PubMed Central

    Law, S W; Brewer, H B

    1984-01-01

    The cDNA clones encoding the precursor form of human liver apolipoprotein A-I (apoA-I), preproapoA-I, have been isolated from a cDNA library. A 17-base synthetic oligonucleotide based on residues 108-113 of apoA-I and a 26-base primer-extended, dideoxynucleotide-terminated cDNA were used as hybridization probes to select for recombinant plasmids bearing the apoA-I sequence. The complete nucleic acid sequence of human liver preproapoA-I has been determined by analysis of the cloned cDNA. The sequence is composed of 801 nucleotides encoding 267 amino acid residues. PreproapoA-I contains an 18-amino-acid prepeptide and a 6-amino-acid propeptide connected to the amino terminus of the 243-amino acid mature apoA-I. Southern blotting analysis of chromosomal DNA obtained from peripheral blood indicated the apoA-I gene is contained in a 2.1-kilobase-pair Pst I fragment and there is no gross difference in structural organization between the normal apoA-I gene and the Tangier disease apoA-I gene. Images PMID:6198645

  6. Human Apolipoprotein A-I Natural Variants: Molecular Mechanisms Underlying Amyloidogenic Propensity

    PubMed Central

    Ramella, Nahuel A.; Schinella, Guillermo R.; Ferreira, Sergio T.; Prieto, Eduardo D.; Vela, María E.; Ríos, José Luis

    2012-01-01

    Human apolipoprotein A-I (apoA-I)-derived amyloidosis can present with either wild-type (Wt) protein deposits in atherosclerotic plaques or as a hereditary form in which apoA-I variants deposit causing multiple organ failure. More than 15 single amino acid replacement amyloidogenic apoA-I variants have been described, but the molecular mechanisms involved in amyloid-associated pathology remain largely unknown. Here, we have investigated by fluorescence and biochemical approaches the stabilities and propensities to aggregate of two disease-associated apoA-I variants, apoA-IGly26Arg, associated with polyneuropathy and kidney dysfunction, and apoA-ILys107-0, implicated in amyloidosis in severe atherosclerosis. Results showed that both variants share common structural properties including decreased stability compared to Wt apoA-I and a more flexible structure that gives rise to formation of partially folded states. Interestingly, however, distinct features appear to determine their pathogenic mechanisms. ApoA-ILys107-0 has an increased propensity to aggregate at physiological pH and in a pro-inflammatory microenvironment than Wt apoA-I, whereas apoA-IGly26Arg elicited macrophage activation, thus stimulating local chronic inflammation. Our results strongly suggest that some natural mutations in apoA-I variants elicit protein tendency to aggregate, but in addition the specific interaction of different variants with macrophages may contribute to cellular stress and toxicity in hereditary amyloidosis. PMID:22952757

  7. The Conformation of Lipid-Free Human Apolipoprotein A-I in Solution

    PubMed Central

    Pollard, Ricquita D.; Fulp, Brian; Samuel, Michael P.; Sorci-Thomas, Mary G.; Thomas, Michael J.

    2014-01-01

    Apolipoprotein AI (apoA-I) is the principal acceptor of lipids from ATP-binding cassette transporter A1, a process that yields nascent high density lipoproteins. Analysis of lipidated apoA-I conformation yields a belt or twisted belt in which two strands of apoA-I lie antiparallel to one another. In contrast, biophysical studies have suggested that a part of lipid-free apoA-I was arranged in a 4-helix bundle. To understand how lipid-free apoA-I opens from a bundle to a belt while accepting lipid it was necessary to have a more refined model for the conformation of lipid-free apoA-I. This study reports the conformation of lipid-free human apoA-I using lysine-to-lysine chemical cross-linking in conjunction with disulfide cross-linking achieved using selective cysteine mutations. After proteolysis cross-linked peptides were verified by sequencing using tandem mass spectrometry. The resulting structure is compact with roughly 4 helical regions, amino acids 44 through 186, bundled together. C- and N-terminal ends, amino acids 1-43 and 187-243, respectively, are folded such that they lie close to one another. An unusual feature of the molecule is the high degree of connectivity of lysine40 with 6 other lysines, lysines that are close, e.g., lysine59, to distant lysines, e.g., lysine239, that are at the opposite end of the primary sequence. These results are compared and contrasted with other reported conformations for lipid-free human apoA-I and an NMR study of mouse apoA-I. PMID:24308268

  8. Interaction of human apolipoprotein A-I with model membranes exhibiting lipid domains.

    PubMed

    Arnulphi, Cristina; Sánchez, Susana A; Tricerri, M Alejandra; Gratton, Enrico; Jonas, Ana

    2005-07-01

    Several mechanisms for cell cholesterol efflux have been proposed, including membrane microsolubilization, suggesting that the existence of specific domains could enhance the transfer of lipids to apolipoproteins. In this work isothermal titration calorimetry, circular dichroism spectroscopy, and two-photon microscopy are used to study the interaction of lipid-free apolipoprotein A-I (apoA-I) with small unilamellar vesicles (SUVs) of 1-palmitoyl, 2-oleoyl phosphatidylcholine (POPC) and sphingomyelin (SM), with and without cholesterol. Below 30 degrees C the calorimetric results show that apoA-I interaction with POPC/SM SUVs produces an exothermic reaction, characterized as nonclassical hydrophobic binding. The heat capacity change (DeltaCp degrees ) is small and positive, whereas it was larger and negative for pure POPC bilayers, in the absence of SM. Inclusion of cholesterol in the membranes induces changes in the observed thermodynamic pattern of binding and counteracts the formation of alpha-helices in the protein. Above 30 degrees C the reactions are endothermic. Giant unilamellar vesicles (GUVs) of identical composition to the SUVs, and two-photon fluorescence microscopy techniques, were utilized to further characterize the interaction. Fluorescence imaging of the GUVs indicates coexistence of lipid domains under 30 degrees C. Binding experiments and Laurdan generalized-polarization measurements suggest that there is no preferential binding of the labeled apoA-I to any particular domain. Changes in the content of alpha-helix, binding, and fluidity data are discussed in the framework of the thermodynamic parameters.

  9. Effects of red grape juice consumption on high density lipoprotein-cholesterol, apolipoprotein AI, apolipoprotein B and homocysteine in healthy human volunteers.

    PubMed

    Khadem-Ansari, Mohammad H; Rasmi, Yousef; Ramezani, Fatemeh

    2010-01-01

    It has suggested that grape juice consumption has lipid- lowering effect and it is associated with a decreased risk of heart disease. We aimed to evaluate the effects of red grape juice (RGj) consumption on high density lipoprotein-cholesterol (HDL-C), apolipoprotein AI (apoAI), apolipoprotein B (apoB) and homocysteine (Hcy) levels in healthy human volunteers. Twenty six healthy and nonsmoking males, aged between 25-60 years, who were under no medication asked to consume 150 ml of RGj twice per day for one month. Serum HDL-C, apoAI, apoB and plasma Hcy levels were measured before and after one month RGj consumption. HDL-C levels after RGj consumption were significantly higher than the corresponding levels before the RGj consumption (41.44 ± 4.50 and 44.37 ± 4.30 mg/dl; P<0.0001). Also, apoB was significantly increased after RGj consumption (149.0 ± 22.35 and 157.19 ± 18.60 mg/dl; P<0.002). But apoAI levels were not changed significantly before and after of RGj consumption (154.27 ± 21.55 and 155.35 ± 21.07 mg/dl; P>0.05). Hcy levels were decreased after RGj consumption (7.70 ± 2.80 and 6.20 ± 2.30 µmol/l; P<0.001). The present study demonstrates that RGj consumption can significantly increase serum HDL-C levels and decrease Hcy levels. These findings may have important implications for the prevention of atherosclerosis in healthy individuals.

  10. Apolipoprotein A-I structural organization in high density lipoproteins isolated from human plasma

    PubMed Central

    Huang, Rong; Gangani D. Silva, R. A.; Jerome, W. Gray; Kontush, Anatol; Chapman, M. John; Curtiss, Linda K.; Hodges, Timothy J.; Davidson, W. Sean

    2010-01-01

    High density lipoproteins (HDL) mediate cholesterol transport and protection from cardiovascular disease. Although synthetic HDLs have been studied for 30 years, the structure of human plasma-derived HDL, and its major protein apolipoprotein (apo)A-I, is unknown. We separated normal human HDL into 5 density subfractions and then further isolated those containing predominantly apoA-I (LpA-I). Using cross-linking chemistry and mass spectrometry, we found that apoA-I adopts a structural framework in these particles that closely mirrors that in synthetic HDL. We adapted established structural models for synthetic HDL to generate the first detailed models of authentic human plasma HDL in which apoA-I adopts a symmetrical cage-like structure. The models suggest that HDL particle size is modulated via a twisting motion of the resident apoA-I molecules. This understanding offers insights into how apoA-I structure modulates HDL function and its interactions with other apolipoproteins. PMID:21399642

  11. Effect of TNF{alpha} on activities of different promoters of human apolipoprotein A-I gene

    SciTech Connect

    Orlov, Sergey V.; Mogilenko, Denis A.; Shavva, Vladimir S.; Dizhe, Ella B.; Ignatovich, Irina A.; Perevozchikov, Andrej P.

    2010-07-23

    Research highlights: {yields} TNF{alpha} stimulates the distal alternative promoter of human apoA-I gene. {yields} TNF{alpha} acts by weakening of promoter competition within apoA-I gene (promoter switching). {yields} MEK1/2 and nuclear receptors PPAR{alpha} and LXRs take part in apoA-I promoter switching. -- Abstract: Human apolipoprotein A-I (ApoA-I) is a major structural and functional protein component of high-density lipoproteins. The expression of the apolipoprotein A-I gene (apoA-I) in hepatocytes is repressed by pro-inflammatory cytokines such as IL-1{beta} and TNF{alpha}. Recently, two novel additional (alternative) promoters for human apoA-I gene have been identified. Nothing is known about the role of alternative promoters in TNF{alpha}-mediated downregulation of apoA-I gene. In this article we report for the first time about the different effects of TNF{alpha} on two alternative promoters of human apoA-I gene. Stimulation of HepG2 cells by TNF{alpha} leads to activation of the distal alternative apoA-I promoter and downregulation of the proximal alternative and the canonical apoA-I promoters. This effect is mediated by weakening of the promoter competition within human apoA-I 5'-regulatory region (apoA-I promoter switching) in the cells treated by TNF{alpha}. The MEK1/2-ERK1/2 cascade and nuclear receptors PPAR{alpha} and LXRs are important for TNF{alpha}-mediated apoA-I promoter switching.

  12. A facile method for isolation of recombinant human apolipoprotein A-I from E. coli.

    PubMed

    Ikon, Nikita; Shearer, Jennifer; Liu, Jianfang; Tran, Jesse J; Feng, ShiBo; Kamei, Ayako; Beckstead, Jennifer A; Kiss, Robert S; Weers, Paul M; Ren, Gang; Ryan, Robert O

    2017-03-20

    Apolipoprotein (apo) A-I is the major protein component of high-density lipoprotein (HDL) and plays key roles in the Reverse Cholesterol Transport pathway. In the past decade, reconstituted HDL (rHDL) has been employed as a therapeutic agent for treatment of atherosclerosis. The ability of rHDL to promote cholesterol efflux from peripheral cells has been documented to reduce the size of atherosclerotic plaque lesions. However, development of apoA-I rHDL-based therapeutics for human use requires a cost effective process to generate an apoA-I product that meets "Good Manufacturing Practice" standards. Methods available for production and isolation of unmodified recombinant human apoA-I at scale are cumbersome, laborious and complex. To overcome this obstacle, a streamlined two-step procedure has been devised for isolation of recombinant untagged human apoA-I from E. coli that takes advantage of its ability to re-fold to a native conformation following denaturation. Heat treatment of a sonicated E. coli supernatant fraction induced precipitation of a large proportion of host cell proteins (HCP), yielding apoA-I as the major soluble protein. Reversed-phase HPLC of this material permitted recovery of apoA-I largely free of HCP and endotoxin. Purified apoA-I possessed α-helix secondary structure, formed rHDL upon incubation with phospholipid and efficiently promoted cholesterol efflux from cholesterol loaded J774 macrophages.

  13. Amyloidogenic Propensity of a Natural Variant of Human Apolipoprotein A-I: Stability and Interaction with Ligands

    PubMed Central

    Rosú, Silvana A.; Rimoldi, Omar J.; Prieto, Eduardo D.; Curto, Lucrecia M.; Delfino, José M.

    2015-01-01

    A number of naturally occurring mutations of human apolipoprotein A-I (apoA-I) have been associated with hereditary amyloidoses. The molecular mechanisms involved in amyloid-associated pathology remain largely unknown. Here we examined the effects of the Arg173Pro point mutation in apoA-I on the structure, stability, and aggregation propensity, as well as on the ability to bind to putative ligands. Our results indicate that the mutation induces a drastic loss of stability, and a lower efficiency to bind to phospholipid vesicles at physiological pH, which could determine the observed higher tendency to aggregate as pro-amyloidogenic complexes. Incubation under acidic conditions does not seem to induce significant desestabilization or aggregation tendency, neither does it contribute to the binding of the mutant to sodium dodecyl sulfate. While the binding to this detergent is higher for the mutant as compared to wt apoA-I, the interaction of the Arg173Pro variant with heparin depends on pH, being lower at pH 5.0 and higher than wt under physiological pH conditions. We suggest that binding to ligands as heparin or other glycosaminoglycans could be key events tuning the fine details of the interaction of apoA-I variants with the micro-environment, and probably eliciting the toxicity of these variants in hereditary amyloidoses. PMID:25950566

  14. Definition of human apolipoprotein A-I epitopes recognized by autoantibodies present in patients with cardiovascular diseases.

    PubMed

    Teixeira, Priscila Camillo; Ducret, Axel; Ferber, Philippe; Gaertner, Hubert; Hartley, Oliver; Pagano, Sabrina; Butterfield, Michelle; Langen, Hanno; Vuilleumier, Nicolas; Cutler, Paul

    2014-10-10

    Autoantibodies to apolipoprotein A-I (anti-apoA-I IgG) have been shown to be both markers and mediators of cardiovascular disease, promoting atherogenesis and unstable atherosclerotic plaque. Previous studies have shown that high levels of anti-apoA-I IgGs are independently associated with major adverse cardiovascular events in patients with myocardial infarction. Autoantibody responses to apoA-I can be polyclonal and it is likely that more than one epitope may exist. To identify the specific immunoreactive peptides in apoA-I, we have developed a set of methodologies and procedures to isolate, purify, and identify novel apoA-I endogenous epitopes. First, we generated high purity apoA-I from human plasma, using thiophilic interaction chromatography followed by enzymatic digestion specifically at lysine or arginine residues. Immunoreactivity to the different peptides generated was tested by ELISA using serum obtained from patients with acute myocardial infarction and high titers of autoantibodies to native apoA-I. The immunoreactive peptides were further sequenced by mass spectrometry. Our approach successfully identified two novel immunoreactive peptides, recognized by autoantibodies from patients suffering from myocardial infarction, who contain a high titer of anti-apoA-I IgG. The discovery of these epitopes may open innovative prognostic and therapeutic opportunities potentially suitable to improve current cardiovascular risk stratification.

  15. Comparative models for human apolipoprotein A-I bound to lipid in discoidal high-density lipoprotein particles.

    PubMed

    Klon, Anthony E; Segrest, Jere P; Harvey, Stephen C

    2002-09-10

    We have constructed a series of models for apolipoprotein A-I (apo A-I) bound to discoidal high-density lipoprotein (HDL) particles, based upon the molecular belt model [Segrest, J. P., et al. (1999) J. Biol. Chem. 274, 31755-31758] and helical hairpin models [Rogers, D. P., et al. (1998) Biochemistry 37, 11714-11725], and compared these with picket fence models [Phillips, J. C., et al. (1997) Biophys. J. 73, 2337-2346]. Molecular belt models for discoidal HDL particles with differing diameters are presented, illustrating that the belt model can explain the discrete changes in HDL particle size observed experimentally. Hairpin models are discussed for the binding of apo A-I to discoidal HDL particles with diameters identical to those for the molecular belt model. Two models are presented for the binding of three monomers of apo A-I to a 150 A diameter discoidal HDL particle. In one model, two monomers of apo A-I bind to the exterior of the HDL particle in an antiparallel belt, with a third monomer of apo A-I bound to the disk in a hairpin conformation. In the second model, all three monomers of apo A-I are bound to the discoidal HDL particle in a hairpin conformation. Previously published experimental data for each model are reviewed, with FRET favoring either the belt or hairpin models over the picket fence models for HDL particles with diameters of 105 A. Naturally occurring mutations appear to favor the belt model for the 105 A particles, while the 150 A HDL particles favor the presence of at least one hairpin.

  16. D-4F, an apolipoprotein A-I mimetic, inhibits TGF-β1 induced epithelial-mesenchymal transition in human alveolar epithelial cell.

    PubMed

    You, Jia; Wang, Jintao; Xie, Linshen; Zhu, Chengwen; Xiong, Jingyuan

    2016-10-01

    Emerging evidences support that transforming growth factor β1 (TGF-β1) induced epithelial-mesenchymal transition (EMT) participates in the pathogenesis of pulmonary fibrosis and asthmatic airway remodeling. Recent studies demonstrated that apolipoprotein A-I (Apo A-I) is the only known substance that can resolve established pulmonary fibrotic nodules, and Apo A-I mimetic D-4F (a synthetic polypeptide consisting of 18 amino acids) plays an inhibitory role in murine asthmatic model. However, cellular mechanisms for such therapeutic effects of Apo A-I and D-4F remain to be elucidated. This study evaluated the effects of D-4F on TGF-β1 induced EMT in human type II alveolar epithelial cell line A549. A549 cells treated with 10ng/ml of TGF-β1 manifested distinct EMT, including fibroblastic morphological changes, down-regulation of epithelial marker E-cadherin and up-regulation of mesenchymal marker vimentin. These EMT related changes were all inhibited by D-4F in a concentration dependent manner. Transcriptional investigation demonstrated clearly that D-4F dose-dependently compensated for the reduced E-cadherin mRNA level and the increased vimentin mRNA level in TGF-β1 treated A549 cells. Translational analysis revealed that D-4F significantly reversed the TGF-β1 induced changes of E-cadherin and vimentin levels. These results suggested that D-4F inhibits TGF-β1 induced EMT in human alveolar epithelial cell. Given the functional similarities between D-4F and Apo A-I, it is speculated that D-4F and Apo A-I are able to exert possible anti-fibrotic and anti-asthmatic effects via inhibiting alveolar EMT, and D-4F may possess beneficial clinical potential for patients suffering from pulmonary fibrosis and asthma.

  17. Docosahexaenoic acid suppresses apolipoprotein A-I gene expression through hepatocyte nuclear factor-3beta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: Dietary fish-oil supplementation has been shown in human kinetic studies to lower the production rate of apolipoprotein (apo) A-I, the major protein component of HDL. The underlying mechanism responsible for this effect is not fully understood. OBJECTIVE: We investigated the effect and...

  18. Conformation and Lipid Binding of a C-Terminal (198-243) Peptide of Human Apolipoprotein A-I (apoA-I)†

    PubMed Central

    Zhu, Hongli L.; Atkinson, David

    2008-01-01

    Human apolipoprotein A-I (apoA-I) is the principle apolipoprotein of high-density lipoproteins that are critically involved in reverse cholesterol transport. The intrinsically flexibility of apoA-I has hindered studies of the structural and functional details of the protein. Our strategy is to study peptide models representing different regions of apoA-I. Our previous report on [1-44]apoA-I demonstrated that this N-terminal region is unstructured and folds into ~ 60% α-helix with a moderate lipid binding affinity. We now present details of the conformation and lipid interaction of a C-terminal 46 residue peptide, [198-243]apoA-I, encompassing putative helix repeats 10, 9 and the second half of repeat 8 from the C-terminus of apoA-I. Far ultraviolet circular dichroism spectra show that [198-243] apoA-I is also unfolded in aqueous solution. However, self-association induces ~ 50% α-helix in the peptide. The self-associated peptide exists mainly as a tetramer, as determined by native electrophoresis, cross-linking with glutaraldehyde and unfolding data from circular dichroism (CD) and differential scanning calorimetry (DSC). In the presence of a number of lipid mimicking detergents, above their CMC, ~ 60% α-helix was induced in the peptide. In contrast, SDS, an anionic lipid mimicking detergent, induced helical folding in the peptide at a concentration of ~ 0.003% (~ 100 μM), ~ 70 fold below its typical CMC (0.17–0.23% or 6–8 mM). Both monomeric and tetrameric peptide can solublize dimyristoyl phosphatidyl choline (DMPC) liposomes and fold into ~ 60% α-helix. Fractionation by density gradient ultracentrifugation and visualization by negative staining electromicroscopy, demonstrated that the peptide binds to DMPC with high affinity to form at least two sizes of relatively homogenous discoidal HDL-like particles depending on the initial lipid:peptide ratio. The characteristics (lipid:peptide w/w, diameter and density) of both complexes are similar to those of

  19. Hereditary apolipoprotein AI-associated renal amyloidosis: A diagnostic challenge.

    PubMed

    Samillán-Sosa, Kelly Del Rocío; Sención-Martínez, Gloria; Lopes-Martín, Vanessa; Martínez-González, Miguel Angel; Solé, Manel; Arostegui, Jose Luis; Mesa, Jose; García-Díaz, Juan de Dios; Rodríguez-Puyol, Diego; Martínez-Miguel, Patricia

    2015-01-01

    Hereditary renal amyloidosis is an autosomal dominant condition with considerable overlap with other amyloidosis types. Differential diagnosis is complicated, but is relevant for prognosis and treatment. We describe a patient with nephrotic syndrome and progressive renal failure, who had a mother with renal amiloidosis. Renal biopsy revealed amyloid deposits in glomerular space, with absence of light chains and protein AA. We suspected amyloidosis with fibrinogen A alpha chain deposits, which is the most frequent cause of hereditary amyloidosis in Europe, with a glomerular preferential affectation. However, the genetic study showed a novel mutation in apolipoprotein AI. On reviewing the biopsy of the patient's mother similar glomerular deposits were found, but there were significant deposits in the renal medulla as well, which is typical in APO AI amyloidosis. The diagnosis was confirmed by immunohistochemistry. Apo AI amyloidosis is characterized by slowly progressive renal disease and end-stage renal disease occurs aproximately 3 to 15 years from initial diagnosis. Renal transplantation offers an acceptable graft survival and in these patients with hepatorenal involvement simultaneous liver and kidney transplantation could be considered.

  20. Apolipoproteins A-I, A-II and E in cholestatic liver disease.

    PubMed

    Florén, C H; Gustafson, A

    1985-04-01

    Apolipoproteins A-I, A-II and E were determined in the plasma of nine patients (five females, four males) with cholestatic liver disease (eight patients with primary biliary cirrhosis and one patient with sclerosing cholangitis). Plasma concentrations were measured by electroimmunoassay in the fasting state, postprandially after ingestion of either 100 g fat as whipping cream or a light mixed meal with or without addition of wheat fibre. Concentrations of apolipoproteins A-I and A-II were low in patients with cholestatic liver disease and A-I levels correlated inversely with the severity of liver disease as measured by bilirubin levels (r = -0.66). No changes in plasma apolipoprotein A-I, A-II or E concentrations occurred postprandially. There was an inverse correlation between plasma concentrations of apolipoproteins A-I and E (p less than 0.05, r = -0.68). A close relation existed between the ratio of apolipoprotein E to apolipoprotein A-I and plasma bile salt concentration (r = 0.80, p less than 0.01) and serum bilirubin (r = 0.76, p less than 0.01). This implies that in cholestatic liver disease apolipoprotein E and A-I levels reflect the degree of cholestasis.

  1. The effects of ginger on fasting blood sugar, hemoglobin a1c, apolipoprotein B, apolipoprotein a-I and malondialdehyde in type 2 diabetic patients.

    PubMed

    Khandouzi, Nafiseh; Shidfar, Farzad; Rajab, Asadollah; Rahideh, Tayebeh; Hosseini, Payam; Mir Taheri, Mohsen

    2015-01-01

    Diabetes mellitus is the most common endocrine disorder, causes many complications such as micro- and macro-vascular diseases. Anti-diabetic, hypolipidemic and anti-oxidative properties of ginger have been noticed in several researches. The present study was conducted to investigate the effects of ginger on fasting blood sugar, Hemoglobin A1c, apolipoprotein B, apolipoprotein A-I, and malondialdehyde in type 2 diabetic patients. In a randomized, double-blind, placebo-controlled, clinical trial, a total of 41 type 2 diabetic patients randomly were assigned to ginger or placebo groups (22 in ginger group and 19 in control group), received 2 g/day of ginger powder supplement or lactose as placebo for 12 weeks. The serum concentrations of fasting blood sugar, Hemoglobin A1c, apolipoprotein B, apolipoprotein A-I and malondialdehyde were analyzed before and after the intervention. Ginger supplementation significantly reduced the levels of fasting blood sugar, hemoglobin A1c, apolipoprotein B, apolipoprotein B/apolipoprotein A-I and malondialdehyde in ginger group in comparison to baseline, as well as control group, while it increased the level of apolipoprotein A-I (p<0.05). It seems that oral administration of ginger powder supplement can improves fasting blood sugar, hemoglobin A1c, apolipoprotein B, apolipoprotein A-I, apolipoprotein B/apolipoprotein A-I and malondialdehyde in type 2 diabetic patients. So it may have a role in alleviating the risk of some chronic complications of diabetes.

  2. Apolipoprotein A-I Q[-2]X causing isolated apolipoprotein A-I deficiency in a family with analphalipoproteinemia.

    PubMed Central

    Ng, D S; Leiter, L A; Vezina, C; Connelly, P W; Hegele, R A

    1994-01-01

    We report a Canadian kindred with a novel mutation in the apolipoprotein (apo) A-I gene causing analphalipoproteinemia. The 34-yr-old proband, product of a consanguineous marriage, had bilateral retinopathy, bilateral cataracts, spinocerebellar ataxia, and tendon xanthomata. High density lipoprotein cholesterol (HDL-C) was < 0.1 mM and apoA-I was undetectable. Genomic DNA sequencing of the proband's apoA-I gene identified a nonsense mutation at codon [-2], which we designate as Q[-2]X. This mutation causes a loss of endonuclease digestion sites for both BbvI and Fnu4HI. Genotyping identified four additional homozygotes, four heterozygotes, and two unaffected subjects among the first-degree relatives. Q[-2]X homozygosity causes a selective failure to produce any portion of mature apoA-I, resulting in very low plasma level of HDL. Heterozygosity results in approximately half-normal apoA-I and HDL. Gradient gel electrophoresis and differential electroimmunodiffusion assay revealed that the HDL particles of the homozygotes had peak Stokes diameter of 7.9 nm and contained apoA-II without apoA-I (Lp-AII). Heterozygotes had an additional fraction of HDL3-like particles. Two of the proband's affected sisters had documented premature coronary heart disease. This kindred, the third reported apoA-I gene mutation causing isolated complete apoA-I deficiency, appears to be at significantly increased risk for atherosclerosis. Images PMID:8282791

  3. Molecules that Mimic Apolipoprotein A-I: Potential Agents for Treating Atherosclerosis

    PubMed Central

    Leman, Luke J.; Maryanoff, Bruce E.; Ghadiri, M. Reza

    2013-01-01

    Certain amphipathic α-helical peptides can functionally mimic many of the properties of full-length apolipoproteins, thereby offering an approach to modulate high-density lipoprotein (HDL) for combating atherosclerosis. In this Perspective, we summarize the key findings and advances over the past 25 years in the development of peptides that mimic apolipoproteins, especially apolipoprotein A-I (apoA-I). This assemblage of information provides a reasonably clear picture of the state of the art in the apolipoprotein mimetic field, an appreciation of the potential for such agents in pharmacotherapy, and a sense of the opportunities for optimizing the functional properties of HDL. PMID:24168751

  4. Immunolocalization of cubilin, megalin, apolipoprotein J, and apolipoprotein A-I in the uterus and oviduct.

    PubMed

    Argraves, W Scott; Morales, Carlos R

    2004-12-01

    Spermatozoa maturation and capacitation occurring in the male and female reproductive tracts, respectively, involves the remodeling of the spermatozoa plasma membrane. Apolipoprotein J (apoJ) and apolipoprotein A-I (apoA-I) have been implicated in the process of lipid exchange from the spermatozoa plasma membrane to epithelial cells lining the male reproductive tract. Evidence suggests that this process is mediated by the cooperative action of the endocytic lipoprotein receptors megalin and cubilin, which are expressed at the apical surface of absorptive epithelia in various tissues, including the efferent ducts and epididymis. Here, we investigated the possibility that these receptors and their lipid-binding ligands, apoJ and apoA-I, might function similarly in the female reproductive tract. We show that megalin and cubilin are expressed in the uterine epithelium at all stages of the estrous cycle, maximally during estrous and metestrous stages. In the oviduct, there is pronounced expression of both megalin and cubilin in the nonciliated cells of the proximal oviduct and epithelial cells of the distal oviduct, particularly during estrous and metestrous stages. In both uterine and oviduct epithelial cells, megalin and cubilin were located on the apical regions of the cells, consistent with a distribution at the cell surface and in endosomes. ApoJ and apoA-I were both detected in apical regions of uterine and oviduct epithelial cells. Secretory cells of the uterine glands were found to express apoJ and apoA-I suggesting that the glands are a site of synthesis for both proteins. In summary, our findings indicate that megalin and cubilin function within the female reproductive tract, possibly mediating uterine and oviduct epithelial cell endocytosis of apoJ/apoA-I-lipid complexes and thus playing a role in lipid efflux from the sperm plasma membrane, a major initiator of capacitation.

  5. Renal apolipoprotein A-I amyloidosis: a rare and usually ignored cause of hereditary tubulointerstitial nephritis.

    PubMed

    Gregorini, Gina; Izzi, Claudia; Obici, Laura; Tardanico, Regina; Röcken, Christoph; Viola, Battista Fabio; Capistrano, Mariano; Donadei, Simona; Biasi, Luciano; Scalvini, Tiziano; Merlini, Giampaolo; Scolari, Francesco

    2005-12-01

    Apolipoprotein A-I amyloidosis is a rare, late-onset, autosomal dominant condition characterized by systemic deposition of amyloid in tissues, the major clinical problems being related to renal, hepatic, and cardiac involvement. Described is the clinical and histologic picture of renal involvement as a result of apolipoprotein A-I amyloidosis in five families of Italian ancestry. In all of the affected family members, the disease was caused by the Leu75Pro heterozygous mutation in exon 4 of apolipoprotein A-I gene, as demonstrated by direct sequencing and RFLP analysis. Immunohistochemistry confirmed that amyloid deposits were specifically stained with an anti-apolipoprotein A-I antibody. The clinical phenotype was mainly characterized by a variable combination of kidney and liver disturbance. The occurrence of renal involvement seemed to be almost universal, although its severity varied greatly ranging from subclinical organ damage to overt, slowly progressive renal dysfunction. The renal presentation was consistent with a tubulointerstitial disease, as suggested by the findings of defective urine-concentrating capacity, moderate polyuria, negative urinalysis, and mild tubular proteinuria. Histology confirmed tubulointerstitial nephritis. Surprising, amyloid was restricted to nonglomerular regions and limited to the renal medulla. This location of apolipoprotein A-I amyloid differs sharply from other systemic amyloidoses that are mainly characterized by glomerular and vascular deposits. The tubulointerstitial nephritis as a result of hereditary apolipoprotein A-I amyloidosis is a rare disease and a challenging diagnosis to recognize. Patients who present with familial tubulointerstitial nephritis associated with liver disease require a high index of suspicion for apolipoprotein A-I amyloidosis.

  6. Expression and recovery of biologically active recombinant Apolipoprotein AI(Milano) from transgenic safflower (Carthamus tinctorius) seeds.

    PubMed

    Nykiforuk, Cory L; Shen, Yin; Murray, Elizabeth W; Boothe, Joseph G; Busseuil, David; Rhéaume, Eric; Tardif, Jean-Claude; Reid, Alexandra; Moloney, Maurice M

    2011-02-01

    Apolipoprotein AI Milano (ApoAI(Milano) ) was expressed as a fusion protein in transgenic safflower seeds. High levels of expression corresponding to 7 g of ApoAI(Milano) per kilogram of seed have been identified in a line selected for commercialization. The ApoAI(Milano) fusion protein was extracted from seed using an oilbody-based process and matured in vitro prior to final purification. This yielded a Des-1,2-ApoAI(Milano) product which was confirmed by biochemical characterization including immunoreactivity against ApoAI antibodies, isoelectric point, N-terminal sequencing and electrospray mass spectrometry. Purified Des-1,2-ApoAI(Milano) readily associated with dimyristoylphosphatidylcholine in clearance assays comparable to Human ApoAI. Its biological activity was assessed by cholesterol efflux assays using Des-1,2-ApoAI(Milano) :1-palmitoyl-2-oleoyl phosphatidylcholine complexes in vitro and in vivo. This study has established that high levels of biologically functional ApoAI(Milano) can be produced using a plant-based expression system.

  7. Apolipoprotein AI and Transthyretin as Components of Amyloid Fibrils in a Kindred with apoAI Leu178His Amyloidosis

    PubMed Central

    de Sousa, Mónica Mendes; Vital, Claude; Ostler, Dominique; Fernandes, Rui; Pouget-Abadie, Jean; Carles, Dominique; Saraiva, Maria João

    2000-01-01

    We found a new C-terminal amyloidogenic variant of apolipoprotein AI (apoAI), Leu178His in a French kindred, associated with cardiac and larynx amyloidosis and skin lesions with onset during the fourth decade. This single-point mutation in exon 4 of the apoAI gene was detected by DNA sequencing of polymerase chain reaction amplified material and restriction fragment length polymorphism analysis in two siblings. Blood, larynx, and skin biopsies were available from one sibling. Anti-apoAI immunoblotting of isoelectric focusing of plasma showed a +1 alteration in the charge of the protein. Extraction of fibrils from the skin biopsy revealed both full-length and N-terminal fragments of apoAI and transthyretin (TTR). ApoAI and TTR co-localized in amyloid deposits as demonstrated by immunohistochemistry. The present report, together with the first recently described C-terminal amyloidogenic variant of apoAI, Arg173Pro, shows that amyloidogenicity of apoAI is not a feature exclusive to N-terminal variants. The most striking characteristic of amyloid fibrils in Leu178His is that wild-type TTR is co-localized with apoAI in the fibrils. We have previously determined that a fraction of plasma TTR circulates in plasma bound to high-density lipoprotein and that this interaction occurs through binding to apoAI. Therefore we hypothesize that nonmutated TTR might influence deposition of apoAI as amyloid. PMID:10854214

  8. Apolipoprotein AI and transthyretin as components of amyloid fibrils in a kindred with apoAI Leu178His amyloidosis.

    PubMed

    de Sousa, M M; Vital, C; Ostler, D; Fernandes, R; Pouget-Abadie, J; Carles, D; Saraiva, M J

    2000-06-01

    We found a new C-terminal amyloidogenic variant of apolipoprotein AI (apoAI), Leu178His in a French kindred, associated with cardiac and larynx amyloidosis and skin lesions with onset during the fourth decade. This single-point mutation in exon 4 of the apoAI gene was detected by DNA sequencing of polymerase chain reaction amplified material and restriction fragment length polymorphism analysis in two siblings. Blood, larynx, and skin biopsies were available from one sibling. Anti-apoAI immunoblotting of isoelectric focusing of plasma showed a +1 alteration in the charge of the protein. Extraction of fibrils from the skin biopsy revealed both full-length and N-terminal fragments of apoAI and transthyretin (TTR). ApoAI and TTR co-localized in amyloid deposits as demonstrated by immunohistochemistry. The present report, together with the first recently described C-terminal amyloidogenic variant of apoAI, Arg173Pro, shows that amyloidogenicity of apoAI is not a feature exclusive to N-terminal variants. The most striking characteristic of amyloid fibrils in Leu178His is that wild-type TTR is co-localized with apoAI in the fibrils. We have previously determined that a fraction of plasma TTR circulates in plasma bound to high-density lipoprotein and that this interaction occurs through binding to apoAI. Therefore we hypothesize that nonmutated TTR might influence deposition of apoAI as amyloid.

  9. Bioinformatic Analysis of Plasma Apolipoproteins A-I and A-II Revealed Unique Features of A-I/A-II HDL Particles in Human Plasma

    PubMed Central

    Kido, Toshimi; Kurata, Hideaki; Kondo, Kazuo; Itakura, Hiroshige; Okazaki, Mitsuyo; Urata, Takeyoshi; Yokoyama, Shinji

    2016-01-01

    Plasma concentration of apoA-I, apoA-II and apoA-II-unassociated apoA-I was analyzed in 314 Japanese subjects (177 males and 137 females), including one (male) homozygote and 37 (20 males and 17 females) heterozygotes of genetic CETP deficiency. ApoA-I unassociated with apoA-II markedly and linearly increased with HDL-cholesterol, while apoA-II increased only very slightly and the ratio of apoA-II-associated apoA-I to apoA-II stayed constant at 2 in molar ratio throughout the increase of HDL-cholesterol, among the wild type and heterozygous CETP deficiency. Thus, overall HDL concentration almost exclusively depends on HDL with apoA-I without apoA-II (LpAI) while concentration of HDL containing apoA-I and apoA-II (LpAI:AII) is constant having a fixed molar ratio of 2 : 1 regardless of total HDL and apoA-I concentration. Distribution of apoA-I between LpAI and LpAI:AII is consistent with a model of statistical partitioning regardless of sex and CETP genotype. The analysis also indicated that LpA-I accommodates on average 4 apoA-I molecules and has a clearance rate indistinguishable from LpAI:AII. Independent evidence indicated LpAI:A-II has a diameter 20% smaller than LpAI, consistent with a model having two apoA-I and one apoA-II. The functional contribution of these particles is to be investigated. PMID:27526664

  10. Novel therapies to increase apolipoprotein AI and HDL for the treatment of atherosclerosis.

    PubMed

    Wong, Norman Cw

    2007-09-01

    Apolipoprotein AI (apoAI) is the major protein component of HDL, and thus has an important role in the treatment of atherosclerosis. This review summarizes the various approaches being examined for raising levels of apoAI/HDL, including increasing the synthesis of apoAI and altering the metabolism of HDL. In addition, the currently available drugs used to increase apoAI/HDL are discussed, with a focus on the potential sites of action of these drugs on HDL metabolism. The outcome of further investigational studies into this field should provide effective therapies to increase apoAI/HDL levels and thus be of use in the treatment of cardiovascular disease.

  11. Characterization of high density lipoprotein particles in familial apolipoprotein A-I deficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our aim was to characterize HDL subspecies and fat-soluble vitamin levels in a kindred with familial apolipoprotein A-I (apoA-I) deficiency. Sequencing of the APOA1 gene revealed a nonsense mutation at codon 22, Q[22]X, with two documented homozygotes, eight heterozygotes, and two normal subjects in...

  12. Apolipoprotein A-I mimetic peptides inhibit expression and activity of hypoxia-inducible factor-1α in human ovarian cancer cell lines and a mouse ovarian cancer model.

    PubMed

    Gao, Feng; Chattopadhyay, Arnab; Navab, Mohamad; Grijalva, Victor; Su, Feng; Fogelman, Alan M; Reddy, Srinivasa T; Farias-Eisner, Robin

    2012-08-01

    Our previous results demonstrated that the apolipoprotein A-I (apoA-I) mimetic peptides L-4F and L-5F inhibit vascular endothelial growth factor production and tumor angiogenesis. The present study was designed to test whether apoA-I mimetic peptides inhibit the expression and activity of hypoxia-inducible factor-1α (HIF-1α), which plays a critical role in the production of angiogenic factors and angiogenesis. Immunohistochemistry staining was used to examine the expression of HIF-1α in tumor tissues. Immunoblotting, real-time polymerase chain reaction, immunofluorescence, and luciferase activity assays were used to determine the expression and activity of HIF-1α in human ovarian cancer cell lines. Immunohistochemistry staining demonstrated that L-4F treatment dramatically decreased HIF-1α expression in mouse ovarian tumor tissues. L-4F inhibited the expression and activity of HIF-1α induced by low oxygen concentration, cobalt chloride (CoCl(2), a hypoxia-mimic compound), lysophosphatidic acid, and insulin in two human ovarian cancer cell lines, OV2008 and CAOV-3. L-4F had no effect on the insulin-induced phosphorylation of Akt, but inhibited the activation of extracellular signal-regulated kinase and p70s6 kinase, leading to the inhibition of HIF-1α synthesis. Pretreatment with L-4F dramatically accelerated the proteasome-dependent protein degradation of HIF-1α in both insulin- and CoCl(2)-treated cells. The inhibitory effect of L-4F on HIF-1α expression is in part mediated by the reactive oxygen species-scavenging effect of L-4F. ApoA-I mimetic peptides inhibit the expression and activity of HIF-1α in both in vivo and in vitro models, suggesting the inhibition of HIF-1α may be a critical mechanism responsible for the suppression of tumor progression by apoA-I mimetic peptides.

  13. Insulin-Mediated Downregulation of Apolipoprotein A-I Gene in Human Hepatoma Cell Line HepG2: The Role of Interaction Between FOXO1 and LXRβ Transcription Factors.

    PubMed

    Shavva, Vladimir S; Bogomolova, Alexandra M; Nikitin, Artemy A; Dizhe, Ella B; Tanyanskiy, Dmitry A; Efremov, Alexander M; Oleinikova, Galina N; Perevozchikov, Andrej P; Orlov, Sergey V

    2017-02-01

    Apolipoprotein A-I (ApoA-I) is a key component of high density lipoproteins which possess anti-atherosclerotic and anti-inflammatory properties. Insulin is a crucial mediator of the glucose and lipid metabolism that has been implicated in atherosclerotic and inflammatory processes. Important mediators of insulin signaling such as Liver X Receptors (LXRs) and Forkhead Box A2 (FOXA2) are known to regulate apoA-I expression in liver. Forkhead Box O1 (FOXO1) is a well-known target of insulin signaling and a key mediator of oxidative stress response. Low doses of insulin were shown to activate apoA-I expression in human hepatoma HepG2 cells. However, the detailed mechanisms for these processes are still unknown. We studied the possible involvement of FOXO1, FOXA2, LXRα, and LXRβ transcription factors in the insulin-mediated regulation of apoA-I expression. Treatment of HepG2 cells with high doses of insulin (48 h, 100 nM) suppresses apoA-I gene expression. siRNAs against FOXO1, FOXA2, LXRβ, or LXRα abrogated this effect. FOXO1 forms a complex with LXRβ and insulin treatment impairs FOXO1/LXRβ complex binding to hepatic enhancer and triggers its nuclear export. Insulin as well as LXR ligand TO901317 enhance the interaction between FOXA2, LXRα, and hepatic enhancer. These data suggest that high doses of insulin downregulate apoA-I gene expression in HepG2 cells through redistribution of FOXO1/LXRβ complex, FOXA2, and LXRα on hepatic enhancer of apoA-I gene. J. Cell. Biochem. 118: 382-396, 2017. © 2016 Wiley Periodicals, Inc.

  14. Inhibition of apolipoprotein A-I gene expression by obesity-associated endocannabinoids.

    PubMed

    Haas, Michael J; Mazza, Angela D; Wong, Norman C W; Mooradian, Arshag D

    2012-04-01

    Obesity is associated with increased serum endocannabinoid (EC) levels and decreased high-density lipoprotein cholesterol (HDLc). Apolipoprotein A-I (apo A-I), the primary protein component of HDL is expressed primarily in the liver and small intestine. To determine whether ECs regulate apo A-I gene expression directly, the effect of the obesity-associated ECs anandamide and 2-arachidonylglycerol on apo A-I gene expression was examined in the hepatocyte cell line HepG2 and the intestinal cell line Caco-2. Apo A-I protein secretion was suppressed nearly 50% by anandamide and 2-arachidonoylglycerol in a dose-dependent manner in both cell lines. Anandamide treatment suppressed both apo A-I mRNA and apo A-I gene promoter activity in both cell lines. Studies using apo A-I promoter deletion constructs indicated that repression of apo A-I promoter activity by anandamide requires a previously identified nuclear receptor binding site designated as site A. Furthermore, anandamide-treatment inhibited protein-DNA complex formation with the site A probe. Exogenous over expression of cannabinoid receptor 1 (CBR1) in HepG2 cells suppressed apo A-I promoter activity, while in Caco-2 cells, exogenous expression of both CBR1 and CBR2 could repress apo A-I promoter activity. The suppressive effect of anandamide on apo A-I promoter activity in Hep G2 cells could be inhibited by CBR1 antagonist AM251 but not by AM630, a selective and potent CBR2 inhibitor. These results indicate that ECs directly suppress apo A-I gene expression in both hepatocytes and intestinal cells, contributing to the decrease in serum HDLc in obese individuals.

  15. Conformational analysis of apolipoprotein A-I and E-3 based on primary sequence and circular dichroism.

    PubMed Central

    Nolte, R T; Atkinson, D

    1992-01-01

    The primary and secondary structure of human plasma apolipoprotein A-I and apolipoprotein E-3 have been analyzed to further our understanding of the secondary and tertiary conformation of these proteins and the structure and function of plasma lipoprotein particles. The methods used to analyze the primary sequence of these proteins used computer programs: (a) to identify repeated patterns within these proteins on the basis of conservative substitutions and similarities within the physicochemical properties of each residue; (b) for local averaging, hydrophobic moment, and Fourier analysis of the physicochemical properties; and (c) for secondary structure prediction of each protein carried out using homology, statistical, and information theory based methods. Circular dichroism was used to study purified lipid-protein complexes of each protein and quantitate the secondary structure in a lipid environment. The data from these analyses were integrated into a single secondary structure prediction to derive a model of each protein. The sequence homology within apolipoproteins A-I, E-3, and A-IV is used to derive a consensus sequence for two 11 amino acid repeating sequences in this family of proteins. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 8 PMID:1477274

  16. The Effect of Aerobic Exercise on Total Cholesterol, High-Density Lipoprotein, Apolipoprotein B, Apolipoprotein A-I, and Percent Body Fat in Adolescent Females.

    ERIC Educational Resources Information Center

    Lungo, Diane; And Others

    The effect of aerobic exercise on total cholesterol (TC), high-density lipoprotein (HDL), apolipoprotein B (Apo B), apolioprotein A-I (Apo A-I), and percent body fat in adolescent females was studied. The control subjects (n=86) were volunteers who had completed a physical education class at least six months prior to the commencement of the study,…

  17. Reaction of discoidal complexes of apolipoprotein A-I and various phosphatidylcholines with lecithin cholesterol acyltransferase. Interfacial effects.

    PubMed

    Jonas, A; Zorich, N L; Kézdy, K E; Trick, W E

    1987-03-25

    Complexes of phospholipids-apolipoprotein A-I-cholesterol, containing various bulk phosphatidylcholines or a matrix of the ether analog of 1-palmitoyl 2-oleoyl phosphatidylcholine including test phosphatidylcholines were used as substrates for human lecithin-cholesterol acyltransferase. The enzymatic reaction rates for both series of complexes were determined as a function of temperature, particle concentration, neutral salt concentration, and the type of anion present in solution. The kinetic results support the hypothesis that phospholipids, in discoidal complexes, modulate the reaction rates by molecular effects at the active site, but also by interfacial effects on the interaction of the enzyme with the particles. The relevant interfacial parameters are the lipid packing at the interface and the structure of apolipoprotein A-I.

  18. Apolipoprotein A-I and its mimetics for the treatment of atherosclerosis

    PubMed Central

    Smith, Jonathan D

    2011-01-01

    Although statin treatment leads consistently to a reduction in major adverse coronary events and death in clinical trials, approximately 60 to 70% residual risk of these outcomes still remains. One frontier of investigational drug research is treatment to increase HDL, the ‘good cholesterol’ that is associated with a reduced risk of coronary artery disease. HDL and its major protein apolipoprotein A-I (apoAI) are protective against atherosclerosis through several mechanisms, including the ability to mediate reverse cholesterol transport. This review focuses on the preclinical and clinical findings for two types of therapies for the treatment of atherosclerosis: apoAI-containing compounds and apoAI mimetic peptides. Both of these therapies have excellent potential to be useful clinically to promote atherosclerosis regression and stabilize existing plaques, but significant hurdles must be overcome in order to develop these approaches into safe and effective therapies. PMID:20730693

  19. Regulation of the promoter of rat apolipoprotein A-I gene in cultured cells

    SciTech Connect

    Chao, Y.; Pan, T.; Wu, T.; Hao, Q.; Yamin, T.; Kroon, P.A.

    1987-05-01

    In order to study the regulation of the promoter of apolipoprotein (apo) A-I gene, they joined the 5' end of rat apo A-I gene (1.9 Kb) to the coding region of bacterial chloramphenicol acetyltransferase (CAT) gene. The chimeric gene produced high levels of CAT activity in both mouse L cells and Hep G2 cells in transient expression assays. Ethanol increased the levels of rat apo A-I promoter activity in both cells. However, dexamethasone increased rat apo A-I promoter activity only in Hep G2 cells. Similar results were obtained in stable expression cell lines. Nucleotide deletion experiments showed DNA sequences between -149 and -469 base pairs upstream from the rat apo A-I transcription site are required for the high level of expression and that the regulatory sequences are located further upstream. These data demonstrated that the 5' end of rat apo A-I gene contains sequences which are responsible for the regulation of apo A-I expression by ethanol and dexamethasone and that the expression and regulation of rat apo A-I promoter are cell specific.

  20. Apolipoprotein A-I mutant proteins having cysteine substitutions and polynucleotides encoding same

    DOEpatents

    Oda, Michael N.; Forte, Trudy M.

    2007-05-29

    Functional Apolipoprotein A-I mutant proteins, having one or more cysteine substitutions and polynucleotides encoding same, can be used to modulate paraoxonase's arylesterase activity. These ApoA-I mutant proteins can be used as therapeutic agents to combat cardiovascular disease, atherosclerosis, acute phase response and other inflammatory related diseases. The invention also includes modifications and optimizations of the ApoA-I nucleotide sequence for purposes of increasing protein expression and optimization.

  1. Effects of dietary maritime pine (Pinus pinaster)-seed oil on high-density lipoprotein levels and in vitro cholesterol efflux in mice expressing human apolipoprotein A-I.

    PubMed

    Asset, G; Leroy, A; Bauge, E; Wolff, R L; Fruchart, J C; Dallongeville, J

    2000-09-01

    Maritime pine (Pinus pinaster)-seed oil contains two Delta5 unsaturated polymethylene interrupted fatty acids (all cis-5,9, 12-18:3 and all cis-5,11,14-20:3 acids) one of which resembles eicosapentaenoic acid. The goal of the present study was to test whether maritime pine-seed oil consumption affects HDL and apolipoprotein (Apo) A-I levels as well as the ability of serum to promote efflux of cholesterol from cultured cells. To this end, wild type (WT) non-transgenic mice and transgenic mice expressing human ApoA-I (HuA-ITg) were fed on isoenergetic diet containing either 200 g maritime pine-seed oil/kg or 200 g lard/kg for 2 weeks. WT and HuA-ITg mice fed maritime pine-seed oil had lower cholesterol, HDL-cholesterol, LDL-cholesterol and HuA-ITg mice had lower human ApoA-I than those fed lard. The differences in cholesterol (P < 0.0001) and HDL-cholesterol (P < 0.003) levels between mice fed on the two diets were more pronounced in the HuA-ITg than in the WT mice. The ability of HuA-ITg serum to promote cholesterol efflux in cultured cells was greater (P < 0.008) than that of WT animals. However, the maritime pine-seed oil diet was associated with lower (P < 0.005) in vitro cholesterol efflux ability than the lard diet in both mice genotypes. This suggests a negative effect of the maritime pine-seed oil on reverse cholesterol transport. Cholesterol efflux was correlated with serum free or esterified cholesterol and phospholipid levels. The slope of the regression line was smaller in the HuA-ITg than in the WT mice indicating that overexpression of human ApoA-I reduces the negative impact of maritime pine-seed oil on cholesterol efflux. In conclusion, maritime pine-seed oil diet lowers HDL-cholesterol and diminishes in vitro cholesterol efflux. This potentially detrimental effect is attenuated by overexpression of human ApoA-I in mice.

  2. Iowa Mutant Apolipoprotein A-I (ApoA-IIowa) Fibrils Target Lysosomes

    PubMed Central

    Kameyama, Hirokazu; Nakajima, Hiroyuki; Nishitsuji, Kazuchika; Mikawa, Shiho; Uchimura, Kenji; Kobayashi, Norihiro; Okuhira, Keiichiro; Saito, Hiroyuki; Sakashita, Naomi

    2016-01-01

    The single amino acid mutation G26R in human apolipoprotein A-I (apoA-IIowa) is the first mutation that was associated with familial AApoA1 amyloidosis. The N-terminal fragments (amino acid residues 1–83) of apoA-I containing this mutation deposit as amyloid fibrils in patients’ tissues and organs, but the mechanisms of cellular degradation and cytotoxicity have not yet been clarified. In this study, we demonstrated degradation of apoA-IIowa fibrils via the autophagy-lysosomal pathway in human embryonic kidney 293 cells. ApoA-IIowa fibrils induced an increase in lysosomal pH and the cytosolic release of the toxic lysosomal protease cathepsin B. The mitochondrial dysfunction caused by apoA-IIowa fibrils depended on cathepsin B and was ameliorated by increasing the degradation of apoA-IIowa fibrils. Thus, although apoA-IIowa fibril transport to lysosomes and fibril degradation in lysosomes may have occurred, the presence of an excess number of apoA-IIowa fibrils, more than the lysosomes could degrade, may be detrimental to cells. Our results thus provide evidence that the target of apoA-IIowa fibrils is lysosomes, and we thereby gained a novel insight into the mechanism of AApoA1 amyloidosis. PMID:27464946

  3. Apolipoprotein A-I metabolism in cynomolgus monkey. Identification and characterization of beta-migrating pools

    SciTech Connect

    Melchior, G.W.; Castle, C.K.

    1989-07-01

    Fresh plasma from control (C) and hypercholesterolemic (HC) cynomolgus monkeys was analyzed by agarose electrophoresis-immunoblotting with antibody to cynomolgus monkey apolipoprotein (apo) A-I. Two bands were evident on the autoradiogram: an alpha-migrating band (high density lipoprotein) and a beta-migrating band that comigrated exactly with cynomolgus monkey low density lipoprotein (LDL). The presence of beta-migrating apo A-I in the plasma of these monkeys was confirmed by Geon-Pevikon preparative electrophoresis, crossed immunoelectrophoresis, and isotope dilution studies in which radiolabeled apo A-I was found to equilibrate also with alpha- and beta-migrating pools of apo A-I in the plasma. Subfractionation of C and HC plasma by agarose column chromatography (Bio-Gel A-0.5M and A-15M) followed by agarose electrophoresis-immunoblotting indicated that the beta-migrating apo A-I in C was relatively homogeneous and eluted with proteins of Mr approximately 50 kD (apo A-I(50 kD)), whereas two beta-migrating fractions were identified in HC, one that eluted with the 50-kD proteins, and the other that eluted in the LDL Mr range (apo A-I(LDL)). The apo A-I(LDL) was precipitated by antibody to cynomolgus monkey apo B. The apo A-I(50 kD) accounted for 5 +/- 1% (mean +/- SD) of the plasma apo A-I in C plasma, and 15 +/- 7% in HC plasma. No apo A-I(LDL) was detected in C plasma, but that fraction accounted for 9 +/- 7% of the apo A-I in HC plasma. These data establish the presence of multiple pools of apo A-I in the cynomolgus monkey, which must be taken into consideration in any comprehensive model of apo A-I metabolism in this species.

  4. A model of lipid-free Apolipoprotein A-I revealed by iterative molecular dynamics simulation

    SciTech Connect

    Zhang, Xing; Lei, Dongsheng; Zhang, Lei; Rames, Matthew; Zhang, Shengli

    2015-03-20

    Apolipoprotein A-I (apo A-I), the major protein component of high-density lipoprotein, has been proven inversely correlated to cardiovascular risk in past decades. The lipid-free state of apo A-I is the initial stage which binds to lipids forming high-density lipoprotein. Molecular models of lipid-free apo A-I have been reported by methods like X-ray crystallography and chemical cross-linking/mass spectrometry (CCL/MS). Through structural analysis we found that those current models had limited consistency with other experimental results, such as those from hydrogen exchange with mass spectrometry. Through molecular dynamics simulations, we also found those models could not reach a stable equilibrium state. Therefore, by integrating various experimental results, we proposed a new structural model for lipidfree apo A-I, which contains a bundled four-helix N-terminal domain (1–192) that forms a variable hydrophobic groove and a mobile short hairpin C-terminal domain (193–243). This model exhibits an equilibrium state through molecular dynamics simulation and is consistent with most of the experimental results known from CCL/MS on lysine pairs, fluorescence resonance energy transfer and hydrogen exchange. This solution-state lipid-free apo A-I model may elucidate the possible conformational transitions of apo A-I binding with lipids in high-density lipoprotein formation.

  5. A model of lipid-free Apolipoprotein A-I revealed by iterative molecular dynamics simulation

    DOE PAGES

    Zhang, Xing; Lei, Dongsheng; Zhang, Lei; ...

    2015-03-20

    Apolipoprotein A-I (apo A-I), the major protein component of high-density lipoprotein, has been proven inversely correlated to cardiovascular risk in past decades. The lipid-free state of apo A-I is the initial stage which binds to lipids forming high-density lipoprotein. Molecular models of lipid-free apo A-I have been reported by methods like X-ray crystallography and chemical cross-linking/mass spectrometry (CCL/MS). Through structural analysis we found that those current models had limited consistency with other experimental results, such as those from hydrogen exchange with mass spectrometry. Through molecular dynamics simulations, we also found those models could not reach a stable equilibrium state. Therefore,more » by integrating various experimental results, we proposed a new structural model for lipidfree apo A-I, which contains a bundled four-helix N-terminal domain (1–192) that forms a variable hydrophobic groove and a mobile short hairpin C-terminal domain (193–243). This model exhibits an equilibrium state through molecular dynamics simulation and is consistent with most of the experimental results known from CCL/MS on lysine pairs, fluorescence resonance energy transfer and hydrogen exchange. This solution-state lipid-free apo A-I model may elucidate the possible conformational transitions of apo A-I binding with lipids in high-density lipoprotein formation.« less

  6. Defective removal of cellular cholesterol and phospholipids by apolipoprotein A-I in Tangier Disease.

    PubMed Central

    Francis, G A; Knopp, R H; Oram, J F

    1995-01-01

    Tangier disease is a rare genetic disorder characterized by extremely low plasma levels of HDL and apo A-I, deposition of cholesteryl esters in tissues, and a high prevalence of cardiovascular disease. We examined the possibility that HDL apolipoprotein-mediated removal of cellular lipids may be defective in Tangier disease. With fibroblasts from normal subjects, purified apo A-I cleared cells of cholesteryl esters, depleted cellular free cholesterol pools available for esterification, and stimulated efflux of radiolabeled cholesterol, phosphatidylcholine, and sphingomyelin. With fibroblasts from two unrelated Tangier patients, however, apo A-I had little or no effect on any of these lipid transport processes. Intact HDL also was unable to clear cholesteryl esters from Tangier cells even though it promoted radiolabeled cholesterol efflux to levels 50-70% normal. Passive desorption of radiolabeled cholesterol or phospholipids into medium containing albumin or trypsinized HDL was normal for Tangier cells. Binding studies showed that the interaction of apo A-I with high-affinity binding sites on Tangier fibroblasts was abnormal. These results indicate that apo A-I has an impaired ability to remove cholesterol and phospholipid from Tangier fibroblasts, possibly because of a defective interaction of apo A-I with cell-surface binding sites. Failure of apo A-I to acquire cellular lipids may account for the rapid catabolism of nascent HDL particles and the low plasma HDL levels in Tangier disease. Images PMID:7615839

  7. Contribution of polymorphisms in the apolipoprotein AI-CIII-AIV cluster to hyperlipidaemia in patients with gout

    PubMed Central

    Cardona, F; Tinahones, F; Collantes, E; Escudero, A; Garcia-Fuentes, E; Soriguer, F

    2005-01-01

    Background: Studies have shown that hyperuricaemia is independently related to the insulin resistance syndrome and that polymorphisms of the apolipoprotein AI-CIII-AIV cluster are also related to insulin resistance. Objective: To study the prevalence of polymorphisms of the apolipoprotein AI-CIII-AIV cluster in persons with gout and to determine whether these polymorphisms contribute to the pathophysiology of gout or to altered lipid concentrations. Methods: Plasma cholesterol, triglycerides, uric acid, VLDL, LDL, IDL, and HDL triglycerides, cholesterol, and the renal excretion of uric acid were measured in 68 patients with gout with gout and 165 healthy subjects. Polymorphisms were studied by amplification and RFLP in all subjects, using XmnI and MspI in the apolipoprotein AI gene and SstI in the apolipoprotein CIII gene. Results: The A allele at position –75 bp in the apolipoprotein AI gene was more common in patients with gout than in controls (p = 0.01). Levels of cholesterol, triglycerides, uric acid, basal glycaemia, and HDL cholesterol were higher in the patients (p<0.001). In the patients there was also an interaction between mutations at the two polymorphic loci studied in the apolipoprotein AI gene (p = 0.04). An absence of the mutation at position –75 bp of the apolipoprotein AI gene resulted in increased plasma triglyceride levels. Conclusions: Gouty patients have an altered allelic distribution in the apolipoprotein AI-CIII-AIV cluster, which could lead to changes in levels of lipoproteins. This is not caused by a single mutation but rather by a combination of different mutations. PMID:15115711

  8. Concentration and pattern changes of porcine serum apolipoprotein A-I in four different infectious diseases.

    PubMed

    Marco-Ramell, Anna; Hummel, Karin; Razzazi-Fazeli, Ebrahim; Bassols, Anna; Miller, Ingrid

    2015-02-01

    Apolipoprotein A-I (Apo A-I) is a major protein in lipid/lipoprotein metabolism and decreased serum levels have been observed in many species in response to inflammatory and infectious challenges. Little is known about the porcine homologue, therefore in this work we have characterized it through biochemical and proteomic techniques. In 2DE, porcine serum Apo A-I is found as three spots, the two more acidic ones corresponding to the mature protein, the more basic spot to the protein precursor. Despite high sequence coverage in LC-MS/MS, we did not find a sequence or PTM difference between the two mature protein species. Besides this biochemical characterization, we measured overall levels and relative species abundance of serum Apo A-I in four different viral and bacterial porcine infectious diseases. Lower overall amounts of Apo A-I were observed in Salmonella typhimurium and Escherichia coli infections. In the 2DE protein pattern, an increase of the protein precursor together with a lower level of mature protein species were detected in the porcine circovirus type 2-systemic disease and S. typhimurium infection. These results reveal that both the porcine serum Apo A-I concentration and the species pattern are influenced by the nature of the infectious disease.

  9. Proteolysis of Apolipoprotein A-I by Secretory Phospholipase A2

    PubMed Central

    Cavigiolio, Giorgio; Jayaraman, Shobini

    2014-01-01

    In the acute phase of the inflammatory response, secretory phospholipase A2 (sPLA2) reaches its maximum levels in plasma, where it is mostly associated with high density lipoproteins (HDL). Overexpression of human sPLA2 in transgenic mice reduces both HDL cholesterol and apolipoprotein A-I (apoA-I) plasma levels through increased HDL catabolism by an unknown mechanism. To identify unknown PLA2-mediated activities on the molecular components of HDL, we characterized the protein and lipid products of the PLA2 reaction with HDL. Consistent with previous studies, hydrolysis of HDL phospholipids by PLA2 reduced the particle size without changing its protein composition. However, when HDL was destabilized in the presence of PLA2 by the action of cholesteryl ester transfer protein or by guanidine hydrochloride treatment, a fraction of apoA-I, but no other proteins, dissociated from the particle and was rapidly cleaved. Incubation of PLA2 with lipid-free apoA-I produced similar protein fragments in the range of 6–15 kDa, suggesting specific and direct reaction of PLA2 with apoA-I. Mass spectrometry analysis of isolated proteolytic fragments indicated at least two major cleavage sites at the C-terminal and the central domain of apoA-I. ApoA-I proteolysis by PLA2 was Ca2+-independent, implicating a different mechanism from the Ca2+-dependent PLA2-mediated phospholipid hydrolysis. Inhibition of proteolysis by benzamidine suggests that the proteolytic and lipolytic activities of PLA2 proceed through different mechanisms. Our study identifies a previously unknown proteolytic activity of PLA2 that is specific to apoA-I and may contribute to the enhanced catabolism of apoA-I in inflammation and atherosclerosis. PMID:24523407

  10. Induction of the apolipoprotein AI gene by fasting: a relationship with ketosis but not with ketone bodies.

    PubMed

    Haas, M J; Reinacher, D; Pun, K; Wong, N C; Mooradian, A D

    2000-12-01

    Apolipoprotein AI (apoAI) expression is inversely related to the incidence of atherosclerosis. ApoAI expression is also influenced by the nutritional state and diabetes. We used both cell culture and animal models to examine the effect of fasting and ketoacidosis on apoAI gene expression. Two days of food deprivation in rats increased hepatic and intestinal apoAI mRNA by 2.6- and 2.3-fold, respectively (P < .05). The absolute concentration of plasma apoAI did not change. However, the plasma apoAI concentration relative to the plasma concentration of serum proteins was increased 23% (P < .05). In fasting rats, there was a significant positive correlation between the serum beta-hydroxybutyrate concentration and hepatic or intestinal apoAI mRNA level. Despite this correlation, changes in apoAI mRNA are probably not mediated by ketone bodies, since neither hepatic nor intestinal apoAI mRNA levels were altered in rats maintained on a ketogenic diet for 10 days or treated with isobutyramide, an orally active ketone analog. In addition, the activity of the rat apoAI promoter was not altered in Hep G2 cells treated with isobutyramide or fatty acids or exposed to hypoglycemic conditions, while dexamethasone increased promoter activity 1.9-fold (P < .05). These data indicate that metabolic changes other than ketone bodies, such as an increase in plasma glucocorticoids, may account for starvation-induced expression of apoAI.

  11. Effect of an isoenergetic traditional Mediterranean diet on apolipoprotein A-I kinetic in men with metabolic syndrome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of the Mediterranean diet (MedDiet) on high-density lipoprotein (HDL) kinetics has not been studied to date. The objective of this study was therefore to investigate the effect of the MedDiet in the absence of changes in body weight on apolipoprotein (apo) A-I kinetic in men with metaboli...

  12. Endotoxin contamination of apolipoprotein A-I: effect on macrophage proliferation--a cautionary tale.

    PubMed

    Jin, Xueting; Xu, Qing; Champion, Keith; Kruth, Howard S

    2015-05-01

    This technical report addresses the problem of endotoxin contamination of apolipoprotein reagents. Using a bromodeoxyuridine incorporation cell proliferation assay, we observed that human plasma ApoA-I as low as 1 μg/ml resulted in a >90% inhibition in macrophage proliferation. However, not all ApoA-I from different sources showed this effect. We considered the possibility that endotoxin contamination of the apolipoproteins contributed to the differential inhibition of macrophage cell proliferation. Endotoxin alone very potently inhibited macrophage proliferation (0.1 ng/ml inhibited macrophage proliferation>90%). Measurement of endotoxin levels in the apolipoprotein products, including an analysis of free versus total endotoxin, the latter which included endotoxin that was masked due to binding to protein, suggested that free endotoxin mediated inhibition of macrophage proliferation. Despite the use of an advanced endotoxin removal procedure and agents commonly used to inhibit endotoxin action, the potency of endotoxin precluded successful elimination of endotoxin effect. Our findings show that endotoxin contamination can significantly influence apparent apolipoprotein-mediated cell effects (or effects of any other biological products), especially when these products are tested on highly endotoxin-sensitive cells, such as macrophages.

  13. Membrane effects of N-terminal fragment of apolipoprotein A-I: a fluorescent probe study.

    PubMed

    Trusova, Valeriya; Gorbenko, Galyna; Girych, Mykhailo; Adachi, Emi; Mizuguchi, Chiharu; Sood, Rohit; Kinnunen, Paavo; Saito, Hiroyuki

    2015-03-01

    The binding of monomeric and aggregated variants of 1-83 N-terminal fragment of apolipoprotein A-I with substitution mutations G26R, G26R/W@8, G26R/W@50 and G26R/W@72 to the model lipid membranes composed of phosphatidylcholine and its mixture with cholesterol has been investigated using fluorescent probes pyrene and Laurdan. Examination of pyrene spectral behavior did not reveal any marked influence of apoA-I mutants on the hydrocarbon region of lipid bilayer. In contrast, probing the membrane effects by Laurdan revealed decrease in the probe generalized polarization in the presence of aggregated proteins. suggesting that oligomeric and fibrillar apoA-I species induce increase in hydration degree and reduction of lipid packing density in the membrane interfacial region. These findings may shed light on molecular details of amyloid cytotoxicity.

  14. Heterogeneous expression of apolipoprotein-E by human macrophages

    PubMed Central

    Tedla, Nicodemus; Glaros, Elias N; Brunk, Ulf T; Jessup, Wendy; Garner, Brett

    2004-01-01

    Apolipoprotein-E (apoE) is expressed at high levels by macrophages. In addition to its role in lipid transport, macrophage-derived apoE plays an important role in immunoregulation. Previous studies have identified macrophage subpopulations that differ substantially in their ability to synthesize specific cytokines and enzymes, however, potential heterogeneous macrophage apoE expression has not been studied. Here we examined apoE expression in human THP-1 macrophages and monocyte-derived macrophages (MDM). Using immunocytochemistry and flow cytometry methods we reveal a striking heterogeneity in macrophage apoE expression in both cell types. In phorbol-ester-differentiated THP-1 macrophages, 5% of the cells over-expressed apoE at levels more than 50-fold higher than the rest of the population. ApoE over-expressing THP-1 macrophages contained condensed/fragmented nuclei and increased levels of activated caspase-3 indicating induction of apoptosis. In MDM, 3–5% of the cells also highly over-expressed apoE, up to 50-fold higher than the rest of the population; however, this was not associated with obvious nuclear alterations. The apoE over-expressing MDM were larger, more granular, and more autofluorescent than the majority of cells and they contained numerous vesicle-like structures that appeared to be coated by apoE. Flow cytometry experiments indicated that the apoE over-expressing subpopulation of MDM were positive for CD14, CD11b/Mac-1 and CD68. These observations suggest that specific macrophage subpopulations may be important for apoE-mediated immunoregulation and clearly indicate that subpopulation heterogeneity should be taken into account when investigating macrophage apoE expression. PMID:15500620

  15. RVX-208, a stimulator of apolipoprotein AI gene expression for the treatment of cardiovascular diseases.

    PubMed

    McNeill, Eileen

    2010-03-01

    RVX-208 (RVX-000222) is a first-in-class, orally active, small-molecule stimulator of apolipoprotein (APO)AI gene expression, which is being developed by Resverlogix Corp for the potential treatment of cardiovascular diseases, in particular atherosclerosis and coronary artery disease. In vitro, RVX-208 stimulated APOAI transcription and was associated with dose-dependent increases in apoAI mRNA and protein. Toxicity studies in animals and phase I/II clinical trials have indicated that RVX-208 is safe and well tolerated in multiple dosing regimens. Plasma exposure to RVX-208 was dose-dependent following single or multiple oral doses and the drug was readily absorbed. In healthy volunteers and patients with low HDL-cholesterol levels, RVX-208 increased total HDL as well as the alpha- and pre-beta HDL fractions that are important substrates in the reverse cholesterol transport pathway. The results of further phase II trials are eagerly awaited to determine whether RVX-208 can deliver plaque regression via improvements in the plasma HDL profile of patients. In addition, a phase I trial indicated that RVX-208 may have potential for the removal of beta-amyloid plaques in Alzheimer's disease and this will be further assessed in an ongoing phase I/II clinical trial.

  16. Expression and purification of recombinant apolipoprotein A-I Zaragoza (L144R) and formation of reconstituted HDL particles.

    PubMed

    Fiddyment, Sarah; Barceló-Batllori, Sílvia; Pocoví, Miguel; García-Otín, Angel-Luis

    2011-11-01

    Apolipoprotein A-I Zaragoza (L144R) (apo A-I Z), has been associated with severe hypoalphalipoproteinemia and an enhanced effect of high density lipoprotein (HDL) reverse cholesterol transport. In order to perform further studies with this protein we have optimized an expression and purification method of recombinant wild-type apo A-I and apo A-I Z and produced mimetic HDL particles with each protein. An pET-45 expression system was used to produce N-terminal His-tagged apo A-I, wild-type or mutant, in Escherichia coli BL21 (DE3) which was subsequently purified by affinity chromatography in non-denaturing conditions. HDL particles were generated via a modified sodium cholate method. Expression and purification of both proteins was verified by SDS-PAGE, MALDI-TOF MS and immunochemical procedures. Yield was 30mg of purified protein (94% purity) per liter of culture. The reconstituted HDL particles checked via non-denaturing PAGE showed high homogeneity in their size when reconstituted both with wild-type apo A-I and apo A-I Z. An optimized system for the expression and purification of wild-type apo A-I and apo A-I Z with high yield and purity grade has been achieved, in addition to their use in reconstituted HDL particles, as a basis for further studies.

  17. Effect of body mass index on apolipoprotein A-I kinetics in middle-aged men and postmenopausal women.

    PubMed

    Welty, Francine K; Lichtenstein, Alice H; Lamon-Fava, Stefania; Schaefer, Ernst J; Marsh, Julian B

    2007-07-01

    The effect of body mass index (BMI) and obesity on apolipoprotein (apo) A-I levels and kinetics was examined by gender. Apo A-I kinetics were determined with a primed, constant infusion of deuterated leucine in the fed state in 19 men and 13 postmenopausal women. Compared with nonobese men, nonobese women had a higher level of high-density lipoprotein cholesterol (HDL-C) and apo A-I due to a 48% higher apo A-I production rate (PR) (P = .05). Obesity had no significant effects on apo A-I kinetics in women. In contrast, compared with nonobese men, obese men had a 9% lower apo A-I level due to a 64% higher fractional catabolic rate (FCR) partially offset by a 47% higher PR. Obese women had a 52% higher HDL-C than obese men (50 vs 33 mg/dL, respectively; P = .012), a finding related to the faster apo A-I FCR in obese men. BMI was directly correlated with apo A-I FCR (r = 0.84, P < .001) and PR (r = 0.79, P < .001) in men but not in women. Sixty-two percent of the variability in PR and 71% of the variability in FCR were due to BMI in men and only 3% and 23%, respectively, in women. In conclusion, BMI has a significant effect on apo A-I PR and FCR in men but not in women.

  18. Interactions between lipid-free apolipoprotein-AI and a lipopeptide incorporating the RGDS cell adhesion motif

    NASA Astrophysics Data System (ADS)

    Castelletto, V.; Hamley, I. W.; Reza, M.; Ruokolainen, J.

    2014-11-01

    The interaction of a designed bioactive lipopeptide C16-GGGRGDS, comprising a hexadecyl lipid chain attached to a functional heptapeptide, with the lipid-free apoliprotein, Apo-AI, is examined. This apolipoprotein is a major component of high density lipoprotein and it is involved in lipid metabolism and may serve as a biomarker for cardiovascular disease and Alzheimers' disease. We find via isothermal titration calorimetry that binding between the lipopeptide and Apo-AI occurs up to a saturation condition, just above equimolar for a 10.7 μM concentration of Apo-AI. A similar value is obtained from circular dichroism spectroscopy, which probes the reduction in α-helical secondary structure of Apo-AI upon addition of C16-GGGRGDS. Electron microscopy images show a persistence of fibrillar structures due to self-assembly of C16-GGGRGDS in mixtures with Apo-AI above the saturation binding condition. A small fraction of spheroidal or possibly ``nanodisc'' structures was observed. Small-angle X-ray scattering (SAXS) data for Apo-AI can be fitted using a published crystal structure of the Apo-AI dimer. The SAXS data for the lipopeptide/Apo-AI mixtures above the saturation binding conditions can be fitted to the contribution from fibrillar structures coexisting with flat discs corresponding to Apo-AI/lipopeptide aggregates.

  19. Macrophage metalloproteinases degrade high-density-lipoprotein-associated apolipoprotein A-I at both the N- and C-termini.

    PubMed Central

    Eberini, Ivano; Calabresi, Laura; Wait, Robin; Tedeschi, Gabriella; Pirillo, Angela; Puglisi, Lina; Sirtori, Cesare R; Gianazza, Elisabetta

    2002-01-01

    Atheromatous plaques contain various cell types, including macrophages, endothelial cells and smooth-muscle cells. To investigate the possible interactions between secreted matrix metalloproteinases and high-density lipoprotein (HDL) components, we tested the above cell types by culturing them for 24 h. HDL(3) (HDL subfractions with average sizes of between 8.44 nm for HDL(3A) and 7.62 nm for HDL(3C)) were then incubated in their cell-free conditioned media. Proteolytic degradation of apolipoprotein A-I was observed with macrophages, but not with endothelial-cell- or muscle-cell-conditioned supernatant. Absence of calcium or addition of EDTA to incubation media prevented all proteolytic processes. The identified apolipoprotein A-I fragments had sizes of 26, 22, 14 and 9 kDa. Two-dimensional electrophoresis and MS resolved the 26 and the 22 kDa components and identified peptides resulting from both N- and C-terminal cleavage of apolipoprotein A-I. The higher abundance of C- than N-terminally cleaved peptides agrees with data in the literature for a fully structured alpha-helix around Tyr(18) compared with an unstructured region around Gly(185) and Gly(186). The flexibility in the latter region of apolipoprotein A-I may explain its susceptibility to proteolysis. In our experimental set-up, HDL(3C) was more extensively degraded than the other HDL(3) subclasses (HDL(3A) and HDL(3B)). Proteolytic fragments produced by metalloproteinase action were shown by gel filtration and electrophoresis to be neither associated with lipids nor self-associated. PMID:11879189

  20. The Concentration of Apolipoprotein A-I Decreases during Experimentally Induced Acute-Phase Processes in Pigs

    PubMed Central

    Carpintero, R.; Piñeiro, M.; Andrés, M.; Iturralde, M.; Alava, M. A.; Heegaard, P. M. H.; Jobert, J. L.; Madec, F.; Lampreave, F.

    2005-01-01

    In this work, apolipoprotein A-I (ApoA-I) was purified from pig sera. The responses of this protein after sterile inflammation and in animals infected with Actinobacillus pleuropneumoniae or Streptococcus suis were investigated. Decreases in the concentrations of ApoA-I, two to five times lower than the initial values, were observed at 2 to 4 days. It is concluded that ApoA-I is a negative acute-phase protein in pigs. PMID:15845530

  1. Tubulointerstitial nephritis is a dominant feature of hereditary apolipoprotein A-I amyloidosis.

    PubMed

    Gregorini, Gina; Izzi, Claudia; Ravani, Pietro; Obici, Laura; Dallera, Nadia; Del Barba, Andrea; Negrinelli, Alessandro; Tardanico, Regina; Nardi, Matilde; Biasi, Luciano; Scalvini, Tiziano; Merlini, Giampaolo; Scolari, Francesco

    2015-06-01

    Apolipoprotein A-I is the main protein of high-density lipoprotein particles, and is encoded by the APOA1 gene. Several APOA1 mutations have been found, either affecting the lecithin:cholesterol acyltransferase activity, determining familial HDL deficiency, or resulting in amyloid formation with prevalent deposits in the kidney and liver. Evaluation of familial tubulointerstitial nephritis in patients with the Leu75Pro APOA-I amyloidosis mutation resulted in the identification of 253 carriers belonging to 50 families from Brescia, Italy. A total of 219 mutation carriers underwent clinical, laboratory, and instrumental tests. Of these, 62% had renal, hepatic, and testicular disease; 38% were asymptomatic. The disease showed an age-dependent penetrance. Tubulointerstitial nephritis was diagnosed in 49% of the carriers, 13% of whom progressed to kidney failure requiring dialysis. Hepatic involvement with elevation of cholestasis indices was diagnosed in 30% of the carriers, 38% of whom developed portal hypertension. Impaired spermatogenesis and hypogonadism was found in 68% of male carriers. The cholesterol levels were lower than normal in 80% of the mutation carriers. Thus, tubulointerstitial nephritis was highly prevalent in this large series of patients with Leu75Pro apoA-I amyloidosis. Persistent elevation of alkaline phosphatase, reduced HDL cholesterol plasma levels, and hypogonadism in men are key diagnostic features of this form of amyloidosis.

  2. Matrix metalloproteinase 8 degrades apolipoprotein A-I and reduces its cholesterol efflux capacity.

    PubMed

    Salminen, Aino; Åström, Pirjo; Metso, Jari; Soliymani, Rabah; Salo, Tuula; Jauhiainen, Matti; Pussinen, Pirkko J; Sorsa, Timo

    2015-04-01

    Various cell types in atherosclerotic lesions express matrix metalloproteinase (MMP)-8. We investigated whether MMP-8 affects the structure and antiatherogenic function of apolipoprotein (apo) A-I, the main protein component of HDL particles. Furthermore, we studied serum lipid profiles and cholesterol efflux capacity in MMP-8-deficient mouse model. Incubation of apoA-I (28 kDa) with activated MMP-8 yielded 22 kDa and 25 kDa apoA-I fragments. Mass spectrometric analyses revealed that apoA-I was cleaved at its carboxyl-terminal part. Treatment of apoA-I and HDL with MMP-8 resulted in significant reduction (up to 84%, P < 0.001) in their ability to facilitate cholesterol efflux from cholesterol-loaded THP-1 macrophages. The cleavage of apoA-I by MMP-8 and the reduction in its cholesterol efflux capacity was inhibited by doxycycline. MMP-8-deficient mice had significantly lower serum triglyceride (TG) levels (P = 0.003) and larger HDL particles compared with wild-type (WT) mice. However, no differences were observed in the apoA-I levels or serum cholesterol efflux capacities between the mouse groups. Proteolytic modification of apoA-I by MMP-8 may impair the first steps of reverse cholesterol transport, leading to increased accumulation of cholesterol in the vessel walls. Eventually, inhibition of MMPs by doxycycline may reduce the risk for atherosclerotic vascular diseases.

  3. Apolipoprotein A-I Helsinki promotes intracellular acyl-CoA cholesterol acyltransferase (ACAT) protein accumulation.

    PubMed

    Toledo, Juan D; Garda, Horacio A; Cabaleiro, Laura V; Cuellar, Angela; Pellon-Maison, Magali; Gonzalez-Baro, Maria R; Gonzalez, Marina C

    2013-05-01

    Reverse cholesterol transport is a process of high antiatherogenic relevance in which apolipoprotein AI (apoA-I) plays an important role. The interaction of apoA-I with peripheral cells produces through mechanisms that are still poorly understood the mobilization of intracellular cholesterol depots toward plasma membrane. In macrophages, these mechanisms seem to be related to the modulation of the activity of acyl-CoA cholesterol acyltransferase (ACAT), the enzyme responsible for the intracellular cholesterol ester biosynthesis that is stored in lipid droplets. The activation of ACAT and the accumulation of lipid droplets play a key role in the transformation of macrophages into foam cells, leading to the formation of atheroma or atherosclerotic plaque. ApoA-I Helsinki (or ∆K107) is a natural apoA-I variant with a lysine deletion in the central protein region, carriers of which have increased atherosclerosis risk. We herein show that treatment of cultured RAW macrophages or CHOK1 cells with ∆K107, but not with wild-type apoA-I or a variant containing a similar deletion at the C-terminal region (∆K226), lead to a marked increase (more than 10 times) in the intracellular ACAT1 protein level as detected by western blot analysis. However, we could only detect a slight increase in cholesteryl ester produced by ∆K107 mainly when Chol loading was supplied by low-density lipoprotein (LDL). Although a similar choline-phospholipid efflux is evoked by these apoA-I variants, the change in phosphatidylcholine/sphyngomyelin distribution produced by wild-type apoA-I is not observed with either ∆K107 or ∆K226.

  4. Apolipoprotein A-I Is a Potential Mediator of Remote Ischemic Preconditioning

    PubMed Central

    Hibert, Pierre; Prunier-Mirebeau, Delphine; Beseme, Olivia; Chwastyniak, Maggy; Tamareille, Sophie; Lamon, Delphine; Furber, Alain; Pinet, Florence; Prunier, Fabrice

    2013-01-01

    Background Remote ischemic preconditioning (RIPC) has emerged as an attractive strategy in clinical settings. Despite convincing evidence of the critical role played by circulating humoral mediators, their actual identities remain unknown. In this study, we aimed to identify RIPC-induced humoral mediators using a proteomic approach. Methods and Results Rats were exposed to 10-min limb ischemia followed by 5- (RIPC 5′) or 10-min (RIPC 10′) reperfusion prior to blood sampling. The control group only underwent blood sampling. Plasma samples were analyzed using surface-enhanced laser desorption and ionization - time of flight - mass spectrometry (SELDI-TOF-MS). Three protein peaks were selected for their significant increase in RIPC 10′. They were identified and confirmed as apolipoprotein A-I (ApoA-I). Additional rats were exposed to myocardial ischemia-reperfusion (I/R) and assigned to one of the following groups RIPC+myocardial infarction (MI) (10-min limb ischemia followed by 10-min reperfusion initiated 20 minutes prior to myocardial I/R), ApoA-I+MI (10 mg/kg ApoA-I injection 10 minutes before myocardial I/R), and MI (no further intervention). In comparison with untreated MI rats, RIPC reduced infarct size (52.2±3.7% in RIPC+MI vs. 64.9±2.6% in MI; p<0.05). Similarly, ApoA-I injection decreased infarct size (50.9±3.8%; p<0.05 vs. MI). Conclusions RIPC was associated with a plasmatic increase in ApoA-I. Furthermore, ApoA-I injection before myocardial I/R recapitulated the cardioprotection offered by RIPC in rats. This data suggests that ApoA-I may be a protective blood-borne factor involved in the RIPC mechanism. PMID:24155931

  5. Apolipoprotein A-I inhibits the production of interleukin-1beta and tumor necrosis factor-alpha by blocking contact-mediated activation of monocytes by T lymphocytes.

    PubMed

    Hyka, N; Dayer, J M; Modoux, C; Kohno, T; Edwards, C K; Roux-Lombard, P; Burger, D

    2001-04-15

    Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), essential components in the pathogenesis of immunoinflammatory diseases, are strongly induced in monocytes by direct contact with stimulated T lymphocytes. This study demonstrates that adult human serum (HS) but not fetal calf or cord blood serum displays inhibitory activity toward the contact-mediated activation of monocytes by stimulated T cells, decreasing the production of both TNF-alpha and IL-1beta. Fractionation of HS and N-terminal microsequencing as well as electroelution of material subjected to preparative electrophoresis revealed that apolipoprotein A-I (apo A-I), a "negative" acute-phase protein, was the inhibitory factor. Functional assays and flow cytometry analyses show that high-density lipoprotein (HDL)-associated apo A-I inhibits contact-mediated activation of monocytes by binding to stimulated T cells, thus inhibiting TNF-alpha and IL-1beta production at both protein and messenger RNA levels. Furthermore, apo A-I inhibits monocyte inflammatory functions in peripheral blood mononuclear cells activated by either specific antigens or lectins without affecting cell proliferation. These results demonstrate a new anti-inflammatory activity of HDL-associated apo A-I that might have modulating functions in nonseptic conditions. Therefore, because HDL has been shown to bind and neutralize lipopolysaccharide, HDL appears to play an important part in modulating both acute and chronic inflammation. The novel anti-inflammatory function of apo A-I reported here might lead to new therapeutic approaches in inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, and atherosclerosis.

  6. High 99mTc-DPD myocardial uptake in a patient with apolipoprotein AI-related amyloidotic cardiomyopathy.

    PubMed

    Quarta, Candida Cristina; Obici, Laura; Guidalotti, Pier Luigi; Pieroni, Maurizio; Longhi, Simone; Perlini, Stefano; Verga, Laura; Merlini, Giampaolo; Rapezzi, Claudio

    2013-03-01

    Amyloidotic cardiomyopathy is still a widely underdiagnosed condition that usually requires endomyocardial biopsy (EMB) for a definite diagnosis. 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) has proven highly sensitive for detecting amyloidotic cardiomyopathy due to transthyretin-related amyloid deposition. Herein we report the first description of the (99mTc-DPD scintigraphy profile in a patient with suspected amyloidotic cardiomyopathy and a final EMB- and genetically-proven diagnosis of familial apolipoprotein AI amyloidosis due to Leu174Ser variant.

  7. Monoclonal antibodies to human apolipoproteins: application to the study of high density lipoprotein subpopulations.

    PubMed

    Bustos, P; Ulloa, N; Calvo, C; Muller, D; Durán, D; Martínez, J; Salazar, L; Quiroga, A

    2000-09-01

    We produced, selected and cloned hybridomas that secrete monoclonal antibodies against human apolipoprotein (apo) A-I. All of the antibodies corresponded to the IgG(1) subclass and were named 1C11, 2B4, 2C10, 7C5, 8A4 and 8A5. The antibodies were characterized by their reactivity with whole lipoproteins, apolipoproteins, synthetic peptides and fragments generated by cleavage of the apo A-I. Three of the monoclonal antibodies studied (2B4, 2C10 and 7C5) were similarly inhibited by an amino-terminal peptide (amino acid sequence 1-20) of apo A-I, whereas antibodies 1C11, 8A4 and 8A5 had no reaction. Other results show that monoclonal antibody 1C11 recognizes an epitope located between amino acids 135-148. We evaluated the monoclonal antibody 8A4 against different HDL subpopulations by competitive displacement analysis and it showed a similar reactivity with the HDL particles: LpA-I and LpA-I:A-II. This antibody was used to standardize a sandwich ELISA to quantitate LpA-I in plasma. We conclude that these monoclonal antibodies are relevant for the study of apo A-I epitope expression and for quantitating apo A-I containing lipoparticles.

  8. Apolipoprotein A-I configuration and cell cholesterol efflux activity of discoidal lipoproteins depend on the reconstitution process.

    PubMed

    Cuellar, Luz Ángela; Prieto, Eduardo Daniel; Cabaleiro, Laura Virginia; Garda, Horacio Alberto

    2014-01-01

    Discoidal high-density lipoproteins (D-HDL) are critical intermediates in reverse cholesterol transport. Most of the present knowledge of D-HDL is based on studies with reconstituted lipoprotein complexes of apolipoprotein A-I (apoA-I) obtained by cholate dialysis (CD). D-HDL can also be generated by the direct microsolubilization (DM) of phospholipid vesicles at the gel/fluid phase transition temperature, a process mechanistically similar to the "in vivo" apoAI lipidation via ABCA1. We compared the apoA-I configuration in D-HDL reconstituted with dimyristoylphosphatidylcholine by both procedures using fluorescence resonance energy transfer measurements with apoA-I tryptophan mutants and fluorescently labeled cysteine mutants. Results indicate that apoA-I configuration in D-HDL depends on the reconstitution process and are consistent with a "double belt" molecular arrangement with different helix registry. As reported by others, a configuration with juxtaposition of helices 5 of each apoAI monomer (5/5 registry) predominates in D-HDL obtained by CD. However, a configuration with helix 5 of one monomer juxtaposed with helix 2 of the other (5/2 registry) would predominate in D-HDL generated by DM. Moreover, we also show that the kinetics of cholesterol efflux from macrophage cultures depends on the reconstitution process, suggesting that apoAI configuration is important for this HDL function.

  9. Plasma lipid transport in the hedgehog: partial characterization of structure and function of apolipoprotein A-I.

    PubMed

    Sparrow, D A; Laplaud, P M; Saboureau, M; Zhou, G; Dolphin, P J; Gotto, A M; Sparrow, J T

    1995-03-01

    Apart from exhibiting the presence of lipoprotein [a] in its plasma, another interest of the European hedgehog in lipoprotein research lies in the quantitative prominence of a complex spectrum of high density lipoproteins (HDL) and very high density lipoproteins (VHDL) as cholesterol transporters in plasma (Laplaud, P. M. et al. 1989. Biochim. Biophys. Acta. 1005: 143-156). We, therefore, initiated studies in the field of reverse cholesterol transport in the hedgehog. As a first step, we characterized apolipoprotein A-I (apoA-I), the main protein component of hedgehog HDL and VHDL. Proteolytic cleavage of apoA-I (M(r) approx. 27 kDa) using two different enzymes resulted in two sets of peptides that were subsequently purified by high performance liquid chromatography, and that allowed us determination of the complete protein sequence. Hedgehog apoA-I thus consists of 241 amino acid residues and exhibits an overall 58% homology to its human counterpart, i.e., the lowest value observed to date among mammalian species. However, it retained the general organization common to all known apoA-Is, i.e., a series of amphipathic helical segments punctuated by proline residues. Circular dichroism experiments indicated a helical content of approx. 45%, increasing to approx. 58% in the presence of lecithin unilamellar liposomes. Apart from other differences, amino acid composition analysis shows that hedgehog apoA-I contains four isoleucine residues, while this amino acid is totally absent from the corresponding protein in higher mammals. Polyclonal antibodies raised against hedgehog apoA-I failed to detect any cross-reactivity between the animal and human proteins, although comparative prediction of the respective antigenic structures using the Hopp-Woods algorithm indicated that several potentially antigenic sites may occur in similar regions of the protein. Finally, hedgehog apoA-I was shown to be able to activate lecithin:cholesterol acyl transferase, although it was 4 to 5

  10. Concentration of apolipoprotein B is comparable with the apolipoprotein B/apolipoprotein A-I ratio and better than routine clinical lipid measurements in predicting coronary heart disease mortality: findings from a multi-ethnic US population

    PubMed Central

    Sierra-Johnson, Justo; Fisher, Rachel M.; Romero-Corral, Abel; Somers, Virend K.; Lopez-Jimenez, Francisco; Öhrvik, John; Walldius, Göran; Hellenius, Mai-Lis; Hamsten, Anders

    2009-01-01

    Aims Prospective studies indicate that apolipoprotein measurements predict coronary heart disease (CHD) risk; however, evidence is conflicting, especially in the US. Our aim was to assess whether measurements of apolipoprotein B (apoB) and apolipoprotein A-I (apoA-I) can improve the ability to predict CHD death beyond what is possible based on traditional cardiovascular (CV) risk factors and clinical routine lipid measurements. Methods and results We analysed prospectively associations of apolipoprotein measurements, traditional CV risk factors, and clinical routine lipid measurements with CHD mortality in a multi-ethnic representative subset of 7594 US adults (mean age 45 years; 3881 men and 3713 women, median follow-up 124 person-months) from the Third National Health and Nutrition Examination Survey mortality study. Multiple Cox-proportional hazards regression was applied. There were 673 CV deaths of which 432 were from CHD. Concentrations of apoB [hazard ratio (HR) 1.98, 95% confidence interval (CI) 1.09–3.61], apoA-I (HR 0.48, 95% CI 0.27–0.85) and total cholesterol (TC) (HR 1.17, 95% CI 1.02–1.34) were significantly related to CHD death, whereas high density lipoprotein cholesterol (HDL-C) (HR 0.68, 95% CI 0.45–1.05) was borderline significant. Both the apoB/apoA-I ratio (HR 2.14, 95% CI 1.11–4.10) and the TC/HDL-C ratio (HR 1.10, 95% CI 1.04–1.16) were related to CHD death. Only apoB (HR 2.01, 95% CI 1.05–3.86) and the apoB/apoA-I ratio (HR 2.09, 95% CI 1.04–4.19) remained significantly associated with CHD death after adjusting for CV risk factors. Conclusion In the US population, apolipoprotein measurements significantly predict CHD death, independently of conventional lipids and other CV risk factors (smoking, dyslipidaemia, hypertension, obesity, diabetes and C-reactive protein). Furthermore, the predictive ability of apoB alone to detect CHD death was better than any of the routine clinical lipid measurements. Inclusion of apolipoprotein

  11. Characterization of High Density Lipoprotein Particles in Familial Apolipoprotein A-I Deficiency With Premature Coronary Atherosclerosis, Corneal Arcus and Opacification, and Tubo-Eruptive and Planar Xanthomas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe two male siblings with homozygous familial apolipoprotein (apo) A-I deficiency, markedly decreased high density lipoprotein (HDL) cholesterol levels, undetectable plasma apoA-1, tubo-eruptive and planar xanthomas, and mild corneal arcus and opacification. Sequencing of the apoA-I gene re...

  12. Safety and Tolerability of CSL112, a Reconstituted, Infusible, Plasma-Derived Apolipoprotein A-I, After Acute Myocardial Infarction

    PubMed Central

    Korjian, Serge; Tricoci, Pierluigi; Daaboul, Yazan; Yee, Megan; Jain, Purva; Alexander, John H.; Steg, P. Gabriel; Lincoff, A. Michael; Kastelein, John J.P.; Mehran, Roxana; D’Andrea, Denise M.; Deckelbaum, Lawrence I.; Merkely, Bela; Zarebinski, Maciej; Ophuis, Ton Oude; Harrington, Robert A.

    2016-01-01

    Background: Human or recombinant apolipoprotein A-I (apoA-I) has been shown to increase high-density lipoprotein–mediated cholesterol efflux capacity and to regress atherosclerotic disease in animal and clinical studies. CSL112 is an infusible, plasma-derived apoA-I that has been studied in normal subjects or those with stable coronary artery disease. This study aimed to characterize the safety, tolerability, pharmacokinetics, and pharmacodynamics of CSL112 in patients with a recent acute myocardial infarction. Methods: The AEGIS-I trial (Apo-I Event Reducing in Ischemic Syndromes I) was a multicenter, randomized, double-blind, placebo-controlled, dose-ranging phase 2b trial. Patients with myocardial infarction were stratified by renal function and randomized 1:1:1 to CSL112 (2 g apoA-I per dose) and high-dose CSL112 (6 g apoA-I per dose), or placebo for 4 consecutive weekly infusions. Coprimary safety end points were occurrence of either a hepatic safety event (an increase in alanine transaminase >3 times the upper limit of normal or an increase in total bilirubin >2 times the upper limit of normal) or a renal safety event (an increase in serum creatinine >1.5 times the baseline value or a new requirement for renal replacement therapy). Results: A total of 1258 patients were randomized, and 91.2% received all 4 infusions. The difference in incidence rates for an increase in alanine transaminase or total bilirubin between both CSL112 arms and placebo was within the protocol-defined noninferiority margin of 4%. Similarly, the difference in incidence rates for an increase in serum creatinine or a new requirement for renal replacement therapy was within the protocol-defined noninferiority margin of 5%. CSL112 was associated with increases in apoA-I and ex vivo cholesterol efflux similar to that achieved in patients with stable coronary artery disease. In regard to the secondary efficacy end point, the risk for the composite of major adverse cardiovascular events

  13. Association of serum lipids and coronary artery disease with polymorphisms in the apolipoprotein AI-CIII-AIV gene cluster

    PubMed Central

    Rai, Himanshu; Sinha, Nakul; Finn, James; Agrawal, Suraksha; Mastana, Sarabjit

    2016-01-01

    Abstract Genetic variants are considered as one of the main determinants of the concentration of serum lipids and coronary artery disease (CAD). Polymorphisms in the Apolipoprotein (Apo) AI-CIII-AIV gene cluster has been known to affect the concentrations of various lipid sub-fractions and the risk of CAD. The present study assessed associations between polymorphisms of the Apo AI-CIII-AIV gene cluster, [ApoA-I,-75G > A, (rs1799837); ApoC-III 3238C > G, (SstI), (rs5128) and ApoA-IV, Thr347Ser(347A > T), (rs675)] with serum lipids and their contributions to CAD in North Indian population. We recruited age, sex matched, 200 CAD patients and 200 healthy controls and tested them for fasting levels of serum lipids. We genotyped selected polymorphisms using polymerase chain reaction-restriction fragment length polymorphism. There were no statistically significant association of selected polymorphisms (or their combinations) with CAD even after employing additive, dominant and recessive models. However there was significant association of selected polymorphisms with various lipid traits amongst the control cohort (p < 0.05). Mean levels of high density lipoprotein cholesterol and triglycerides were found to be significantly higher among controls carrying at least one mutant allele at ApoA1-75G > A (p = 0.019) and ApoCIII SstI (p < 0.001) polymorphism respectively. Our study observed that the selected polymorphisms in the ApoAI-CIII-AIV gene cluster although significantly affect various lipid traits but this affect does not seem to translate into association with CAD, at least among North Indian population. PMID:28261635

  14. Associations of apolipoprotein B/apolipoprotein A-I ratio with pre-diabetes and diabetes risks: a cross-sectional study in Chinese adults

    PubMed Central

    Zheng, Shuang; Han, Tingting; Xu, Hua; Zhou, Huan; Ren, Xingxing; Wu, Peihong; Zheng, Jun; Wang, Lihua; Zhang, Ming; Jiang, Yihong; Chen, Yawen; Qiu, Huiying; Liu, Wei; Hu, Yaomin

    2017-01-01

    Background Apolipoprotein B/apolipoprotein A-I (ApoB/ApoA-I) ratio is a useful predictor of cardiovascular risk. However, the association between the ApoB/ApoA-I ratio and the risk of type 2 diabetes mellitus (T2DM) is still obscure. Aims To investigate the associations between the ApoB/ApoA-I ratio and the risk of T2DM and pre-diabetes in a Chinese population, and to assess the role of gender in these associations. Methods A stratified random sampling design was used in this cross-sectional study which included 264 men and 465 women with normal glucose tolerance (NGT), pre-diabetes or T2DM. Serum ApoB, ApoA-I and other lipid and glycaemic traits were measured. Pearson's partial correlation and multivariable logistic analysis were used to evaluate the associations between ApoB/ApoA-I ratio and the risk of T2DM and pre-diabetes. Results The ApoB/ApoA-I ratios were significantly increased across the spectrum of NGT, pre-diabetes and T2DM. Women showed higher levels of ApoB/ApoA-I ratio and ApoB than men in the pre-diabetic and T2DM groups, but not in the NGT group. The ApoB/ApoA-I ratio was closely related with triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and other glycaemic traits. Moreover, in women, the risk of diabetes and pre-diabetes in the top and middle tertiles of the ApoB/ApoA-I ratio were 3.65-fold (95% CI 1.69 to 6.10) and 2.19-fold (95% CI 1.38 to 2.84) higher than in the bottom tertile, respectively, after adjusting for potential confounding factors. However, the associations disappeared in men after adjusting for other factors. Conclusions The ApoB/ApoA-I ratio showed positive associations with the risk of diabetes and pre-diabetes in Chinese women. PMID:28110289

  15. Human Frontal Lobes and AI Planning Systems

    NASA Technical Reports Server (NTRS)

    Levinson, Richard; Lum, Henry Jr. (Technical Monitor)

    1994-01-01

    Human frontal lobes are essential for maintaining a self-regulating balance between predictive and reactive behavior. This paper describes a system that integrates prediction and reaction based on neuropsychological theories of frontal lobe function. In addition to enhancing our understanding of deliberate action in humans' the model is being used to develop and evaluate the same properties in machines. First, the paper presents some background neuropsychology in order to set a general context. The role of frontal lobes is then presented by summarizing three theories which formed the basis for this work. The components of an artificial frontal lobe are then discussed from both neuropsychological and AI perspectives. The paper concludes by discussing issues and methods for evaluating systems that integrate planning and reaction.

  16. Macrophage apolipoprotein A-I expression protects against atherosclerosis in ApoE-deficient mice and up-regulates ABC transporters.

    PubMed

    Su, Yan Ru; Ishiguro, Hiroyuki; Major, Amy S; Dove, Dwayne E; Zhang, Wenwu; Hasty, Alyssa H; Babaev, Vladimir R; Linton, MacRae F; Fazio, Sergio

    2003-10-01

    The antiatherogenic effect of high-density lipoprotein (HDL) and its major protein component apolipoprotein A-I (apoA-I) has been largely attributed to their key roles in reverse cholesterol transport (RCT) and cellular cholesterol efflux. Substantial evidence shows that overexpression of human apoA-I reduces atherosclerosis in animal models. However, it is uncertain whether this protection is due to an increase in plasma HDL level or to a local effect in the artery wall. To test the hypothesis that expression of human apoA-I in macrophages can promote RCT in the artery wall, we used a retroviral construct expressing human apoA-I cDNA (MFG-HAI) to transduce ApoE(-/-) bone marrow cells and then transplanted these cells into ApoE(-/-) mice with preexisting atherosclerosis. ApoE(-/-) mice reconstituted with MFG-HAI marrow had a significant reduction (30%) in atherosclerotic lesions in the proximal aorta compared to control mice that received marrow expressing MFG parental virus. Peritoneal macrophages isolated from MFG-HAI mice showed a four- to fivefold increase in mRNA expression levels of both ATP-binding cassette (ABC) A1 and ABCG1 compared to controls. Our data demonstrate that gene transfer-mediated expression of human apoA-I in macrophages can compensate in part for apoE deficiency and delay the progression of atherosclerotic lesions by stimulating ABC-dependent cholesterol efflux and RCT.

  17. Elevated high density lipoprotein cholesterol levels correlate with decreased apolipoprotein A-I and A-II fractional catabolic rate in women.

    PubMed Central

    Brinton, E A; Eisenberg, S; Breslow, J L

    1989-01-01

    High levels of HDL-cholesterol (HDL-C) protect against coronary heart disease susceptibility, but the metabolic mechanisms underlying elevated HDL-C levels are poorly understood. We now report the turnover of isologous radioiodinated HDL apolipoproteins, apo A-I and apo A-II, in 15 female subjects on a metabolic diet with HDL-C levels ranging from 51 to 122 mg/dl. The metabolic parameters, fractional catabolic rate (FCR) and absolute synthetic rate (SR), were determined for apo A-I and apo A-II in all subjects. There was an inverse correlation between plasma HDL-C and the FCR of apo A-I and apo A-II (r = -0.75, P less than 0.001, and r = -0.54, P = 0.036, respectively), but no correlation with the SR of either apo A-I or apo A-II (r = 0.09, and r = -0.16, respectively, both P = NS). Apo A-I levels correlated inversely with apo A-I FCR (r = -0.64, P = 0.01) but not with apo A-I SR (r = 0.30, P = NS). In contrast, plasma levels of apo A-II did not correlate with apo A-II FCR (r = -0.38, P = 0.16), but did correlate with apo A-II SR (r = 0.65, P = 0.009). Further analysis showed that apo A-I and apo A-II FCR were inversely correlated with the HDL-C/apo A-I + A-II ratio (r = -0.69 and -0.61, P = 0.005 and 0.015, respectively). These data suggest that: (a) low HDL apolipoprotein FCR is the predominant metabolic mechanism of elevated HDL-C levels; (b) apo A-I FCR is the primary factor in controlling plasma apo A-I levels, but apo A-II SR is the primary factor controlling plasma apo A-II levels; (c) low HDL apolipoprotein FCR is associated with a lipid-rich HDL fraction. These findings elucidate aspects of HDL metabolism which contribute to high HDL-C levels and which may constitute mechanisms for protection against coronary heart disease. PMID:2500457

  18. High-density cholesterol and apolipoprotein AI as modifiers of plasma fibrin clot properties in apparently healthy individuals.

    PubMed

    Ząbczyk, Michał; Hońdo, Łukasz; Krzek, Marzena; Undas, Anetta

    2013-01-01

    Low high-density lipoprotein cholesterol (HDL-C) increases cardiovascular risk, whereas its high levels protect against atherosclerosis via multiple beneficial effects. Dense and poorly lysable fibrin clot formation is observed in cardiovascular disease. We sought to investigate whether HDL-C and its major component apolipoprotein A (Apo A)-I affect fibrin clot properties. In 136 apparently healthy individuals (99 men, 37 women, aged 49-69 years) we determined plasma fibrin clot permeability (Ks coefficient) and lysis time (t50%) together with Apo A-I and lipoprotein (a) [Lp(a)] levels. The median HDL-C level was 1.33  mmol/l (range from 0.77 to 2.19  mmol/l). HDL-C was positively associated with Apo A-I (r = 0.62, P < 0.00001). HDL-C and Apo A-I were positively correlated with Ks (r = 0.52, P < 0.00001 and r = 0.44, P < 0.00001, respectively) and inversely with t50% (r = -0.44, P < 0.00001 and r = -0.35, P = 0.00003, respectively). No such associations were seen for other lipid variables. Ks and t50% were associated with Lp(a) (r = -0.42, P < 0.00001 and r = 0.42, P < 0.00001, respectively) and fibrinogen (r = -0.31, P = 0.00024 and r = 0.39, P < 0.00001, respectively). Individuals with HDL-C at least 1.4 mmol/l (n = 54) had 19% higher Ks (P = 0.00016) and 17% shorter t50% (P = 0.0012) than the remainder. After adjustment for age, fibrinogen, and Lp(a), HDL-C was the independent predictor of Ks (β = 0.7, P < 0.00001) and t50% (β = -0.62, P < 0.00001). This study shows that elevated HDL-C levels are associated with improved fibrin clot permeability and lysis, indicating a novel antithrombotic mechanism underlying the postulated beneficial effects of therapy targeted at HDL-C.

  19. A mass spectrometric determination of the conformation of dimeric apolipoprotein A-I in discoidal high density lipoproteins.

    PubMed

    Silva, R A Gangani D; Hilliard, George M; Li, Ling; Segrest, Jere P; Davidson, W Sean

    2005-06-21

    Discoidal forms of high density lipoproteins (HDL) are critical intermediates between lipid-poor apolipoprotein A-I (apo A-I), the major protein constituent of HDL, and the mature spherical forms that comprise the bulk of circulating particles. Thus, many studies have focused on understanding apoA-I structure in discs reconstituted in vitro. Recent theoretical and experimental work supports a "belt" model for apoA-I in which repeating amphipathic helical domains run parallel to the plane of the lipid disc. However, disc-associated apoA-I can adopt several tertiary arrangements that are consistent with a belt orientation. To distinguish among these, we cross-linked near-neighbor Lys groups in homogeneous 96 A discs containing exactly two molecules of apoA-I. After delipidation and tryptic digestion, mass spectrometry was used to identify 9 intermolecular and 11 intramolecular cross-links. The cross-linking pattern strongly suggests a "double-belt" molecular arrangement for apoA-I in which two apoA-I molecules wrap around the lipid bilayer disc forming two stacked rings in an antiparallel orientation with helix 5 of each apoA-I in juxtaposition (LL5/5 orientation). The data also suggests the presence of an additional double-belt orientation with a shifted helical registry (LL5/2 orientation). Furthermore, a 78 A particle with two molecules of apoA-I fit a similar double-belt motif with evidence for conformational changes in the N-terminus and the region near helix 5. A comparison of this work to a previous study is suggestive that a third molecule of apoA-I can form a hairpin in larger particles containing three molecules of apoA-I.

  20. The effect of chromium picolinate on serum cholesterol and apolipoprotein fractions in human subjects.

    PubMed Central

    Press, R. I.; Geller, J.; Evans, G. W.

    1990-01-01

    Chromium has been implicated as a cofactor in the maintenance of normal lipid and carbohydrate metabolism. A deficiency of chromium results from diets low in biologically available chromium. Picolinic acid, a metabolite of tryptophan, forms stable complexes with transitional metal ions, which results in an improved bioavailability of the metal ion chromium. To determine whether or not chromium picolinate is effective in humans, 28 volunteer subjects were given either chromium tripicolinate (3.8 micromol [200 micrograms] chromium) or a placebo daily for 42 days in a double-blind crossover study. A 14-day period off capsules was used between treatments. Levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, and apolipoprotein B, the principal protein of the LDL fraction, decreased significantly while the subjects were ingesting chromium picolinate. The concentration of apolipoprotein A-I, the principal protein of the high-density lipoprotein (HDL) fraction, increased substantially during treatment with chromium picolinate. The HDL-cholesterol level was elevated slightly but not significantly during ingestion of chromium picolinate. Only apolipoprotein B, of the variables measured, was altered significantly during supplementation with the placebo. These observations show that chromium picolinate is efficacious in lowering blood lipids in humans. PMID:2408233

  1. High-density Lipoproteins and Apolipoprotein A-I: Potential New Players in the Prevention and Treatment of Lung Disease

    PubMed Central

    Gordon, Elizabeth M.; Figueroa, Debbie M.; Barochia, Amisha V.; Yao, Xianglan; Levine, Stewart J.

    2016-01-01

    Apolipoprotein A-I (apoA-I) and high-density lipoproteins (HDL) mediate reverse cholesterol transport out of cells. Furthermore, HDL has additional protective functions, which include anti-oxidative, anti-inflammatory, anti-apoptotic, and vasoprotective effects. In contrast, HDL can become dysfunctional with a reduction in both cholesterol efflux and anti-inflammatory properties in the setting of disease or the acute phase response. These paradigms are increasingly being recognized to be active in the pulmonary system, where apoA-I and HDL have protective effects in normal lung health, as well as in a variety of disease states, including acute lung injury (ALI), asthma, chronic obstructive pulmonary disease, lung cancer, pulmonary arterial hypertension, pulmonary fibrosis, and viral pneumonia. Similar to observations in cardiovascular disease, however, HDL may become dysfunctional and contribute to disease pathogenesis in respiratory disorders. Furthermore, synthetic apoA-I mimetic peptides have been shown to have protective effects in animal models of ALI, asthma, pulmonary hypertension, and influenza pneumonia. These findings provide evidence to support the concept that apoA-I mimetic peptides might be developed into a new treatment that can either prevent or attenuate the manifestations of lung diseases, such as asthma. Thus, the lung is positioned to take a page from the cardiovascular disease playbook and utilize the protective properties of HDL and apoA-I as a novel therapeutic approach. PMID:27708582

  2. Seasonal variation in plasma lipids, lipoproteins, apolipoprotein A-I and vitellogenin in the freshwater turtle, Chrysemys picta.

    PubMed

    Duggan, A; Paolucci, M; Tercyak, A; Gigliotti, M; Small, D; Callard, I

    2001-09-01

    An analysis of plasma lipids and lipoprotein fractions was performed over the course of the annual ovarian cycle of the female turtle, Chrysemys picta. Determinations of total plasma triglycerides, cholesterol, vitellogenin and apolipoprotein A-I (apoA-I) were made. The lipid and protein composition of the lipoprotein fractions [very low density lipoprotein (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL) and very high density lipoprotein (VHDL)] were also observed over the same period. Plasma triglyceride and vitellogenin levels were significantly increased in the spring preovulatory period and fall recrudescent phase. Total plasma cholesterol levels were significantly elevated only at the onset of the fall recrudescent phase and apoA-I levels were highest during the postoviposition/ovarian arrest phase. The triglyceride content of VLDL was highest in preovulatory animals and there were apparent seasonal changes in the expression of apoA-I and apoE of HDL/VHDL. We conclude that the coordinate regulation of lipids and protein contributes to seasonal ovarian growth and clearance of lipids from plasma, both of which are most likely under hormonal control.

  3. Effect of lipid-bound apolipoprotein A-I cysteine mutant on ATF3 in RAW264.7 cells

    PubMed Central

    Wang, Yunlong; Wang, Yanhui; Jia, Shaoyou; Dong, Qingzhe; Chen, Yuanbin

    2017-01-01

    Activating transcription factor 3 (ATF3) is a TLR-induced repressor that plays an important role in the inhibition of specific inflammatory signals. We previously constructed recombinant high density lipoproteins (rHDL) (including rHDLWT, rHDLM, rHDL228 and rHDL74) and found that rHDL74 had a strong anti-inflammatory ability. In the present study, we investigate the roles of recombinant apolipoprotein A-I (ApoA-I) (rHDLWT) and its cysteine mutant HDLs (rHDLM, rHDL228 and rHDL74) on ATF3 function in RAW264.7 cells stimulated by lipopolysaccharide. Our results showed that compared with the LPS group, rHDL74 can decrease the level of TNF-α and IL-6, whereas rHDL228 increases their expression levels. RT-PCR and Western blotting results showed that compared with the LPS group, rHDL74, rHDLWT and rHDLM can markedly increase the expression level of ATF3, whereas the level of ATF3 decreases in the rHDL228 group. In summary, the different anti-inflammatory mechanisms of the ApoA-I cysteine mutants might be associated with the regulation of ATF3 level. PMID:28093456

  4. Interaction of thioflavin T with amyloid fibrils of apolipoprotein A-I N-terminal fragment: resonance energy transfer study.

    PubMed

    Girych, Mykhailo; Gorbenko, Galyna; Trusova, Valeriya; Adachi, Emi; Mizuguchi, Chiharu; Nagao, Kohjiro; Kawashima, Hiroyuki; Akaji, Kenichi; Lund-Katz, Sissel; Phillips, Michael C; Saito, Hiroyuki

    2014-01-01

    Apolipoprotein A-I is amenable to a number of specific mutations associated with hereditary systemic amyloidoses. Amyloidogenic properties of apoA-I are determined mainly by its N-terminal fragment. In the present study Förster resonance energy transfer between tryptophan as a donor and Thioflavin T as an acceptor was employed to obtain structural information on the amyloid fibrils formed by apoA-I variant 1-83/G26R/W@8. Analysis of the dye-fibril binding data provided evidence for the presence of two types of ThT binding sites with similar stoichiometries (bound dye to monomeric protein molar ratio ∼10), but different association constants (∼6 and 0.1μM(-1)) and ThT quantum yields in fibril-associated state (0.08 and 0.05, respectively). A β-strand-loop-β-strand structural model of 1-83/G26R/W@8 apoA-I fibrils has been proposed, with potential ThT binding sites located in the solvent-exposed grooves of the N-terminal β-sheet layer. Reasoning from the expanded FRET analysis allowing for heterogeneity of ThT binding centers and fibril polymorphism, the most probable locations of high- and low-affinity ThT binding sites were attributed to the grooves T16_Y18 and D20_L22, respectively.

  5. Simvastatin, an HMG-CoA reductase inhibitor, induces the synthesis and secretion of apolipoprotein AI in HepG2 cells and primary hamster hepatocytes.

    PubMed

    Bonn, Victoria; Cheung, Raphael C; Chen, Biao; Taghibiglou, Changiz; Van Iderstine, Stephen C; Adeli, Khosrow

    2002-07-01

    Clinical studies have recently suggested that statin treatment may beneficially elevate plasma concentrations of high density lipoprotein (HDL)-cholesterol in patients with hyperlipidemia. Here, we have investigated the effect of a potent inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase on the synthesis and secretion of apolipoprotein AI (apoAI) in two model systems, HepG2 cells and primary hamster hepatocytes. Cultured cells were incubated with different doses of simvastatin (0.1-10 microM) for a period of 18 h. A dose-dependent increase in synthesis and secretion of apoAI was observed in both cell types. There was a significant increase in the synthesis of apoAI in HepG2 cells (44.3+/-12.1%), and hamster hepatocytes (212+/-2%) after treatment with 10 microM of the statin. The increase in apoAI synthesis appeared to result in a higher level of apoAI secreted into the culture media in both cell types (49.2+/-7.8% in HepG2, 197+/-0.2% in hamster hepatocytes). ApoAI mRNA levels were also significantly increased in both cell types in response to statin treatment. Control experiments with transferrin confirmed specificity of the effect on apoAI secretion. Analysis of a density fraction containing HDL particles in culture media revealed an increase in HDL-associated apoAI of 94.3+/-2.1% in HepG2 cells and 27.0+/-0.03% in hamster hepatocytes following 10 microM simvastatin-treatment. Comparative studies of simvastatin and lovastatin indicated a differential ability to induce apoAI synthesis and secretion, with simvastatin having a more significant effect. Thus, acute statin treatment of cultured hepatocytes (transformed as well as primary) resulted in a significant upregulation of apoAI mRNA and apoAI synthesis, causing oversecretion of apoAI and HDL extracellularly. The stimulatory effect on apoAI synthesis and secretion may thus explain the clinical observation of an elevated plasma HDL-cholesterol level in hyperlipidemic patients treated with

  6. Decreased apolipoprotein A-I level indicates poor prognosis in extranodal natural killer/T-cell lymphoma, nasal type

    PubMed Central

    Quan, Qi; Chen, Qi; Chen, Ping; Jiang, Li; Li, Tingwei; Qiu, Huijuan; Zhang, Bei

    2016-01-01

    Background Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL) is an invasive lymphoid malignancy with unfavorable survival, for which a prognostic model has not yet been validated. We hypothesized that serum apolipoprotein A-I (ApoA-I) may serve as a novel prognostic marker for ENKTL. Patients and methods A total of 236 newly diagnosed cases of ENKTL were analyzed retrospectively. Results The optimal cutoff value for the serum ApoA-I level was determined to be 0.95 g/L. A total of 154 and 82 cases were assigned to the high and low ApoA-I groups, respectively. Patients in the low ApoA-I group tended to present with poorer clinical features, a lower complete remission rate (P=0.001), and poor median progression-free survival (P<0.001) and overall survival (P<0.001). Multivariate analysis using Cox model showed that the serum ApoA-I level was an independent prognostic marker of overall survival (P<0.001) and progression-free survival (P<0.001) for ENKTL patients. For cases in the low-risk group, as assessed by International Prognostic Index, Prognosis Index for peripheral T-cell lymphoma, unspecified, and Korean Prognostic Index, the serum ApoA-I level was able to differentiate cases with poor outcomes from cases with good outcomes. Conclusion Our results showed that the baseline serum ApoA-I level was helpful for predicting ENKTL prognosis. PMID:27051293

  7. Genome-wide screen for modulation of hepatic apolipoprotein A-I (ApoA-I) secretion.

    PubMed

    Miles, Rebecca R; Perry, William; Haas, Joseph V; Mosior, Marian K; N'Cho, Mathias; Wang, Jian W J; Yu, Peng; Calley, John; Yue, Yong; Carter, Quincy; Han, Bomie; Foxworthy, Patricia; Kowala, Mark C; Ryan, Timothy P; Solenberg, Patricia J; Michael, Laura F

    2013-03-01

    Control of plasma cholesterol levels is a major therapeutic strategy for management of coronary artery disease (CAD). Although reducing LDL cholesterol (LDL-c) levels decreases morbidity and mortality, this therapeutic intervention only translates into a 25-40% reduction in cardiovascular events. Epidemiological studies have shown that a high LDL-c level is not the only risk factor for CAD; low HDL cholesterol (HDL-c) is an independent risk factor for CAD. Apolipoprotein A-I (ApoA-I) is the major protein component of HDL-c that mediates reverse cholesterol transport from tissues to the liver for excretion. Therefore, increasing ApoA-I levels is an attractive strategy for HDL-c elevation. Using genome-wide siRNA screening, targets that regulate hepatocyte ApoA-I secretion were identified through transfection of 21,789 siRNAs into hepatocytes whereby cell supernatants were assayed for ApoA-I. Approximately 800 genes were identified and triaged using a convergence of information, including genetic associations with HDL-c levels, tissue-specific gene expression, druggability assessments, and pathway analysis. Fifty-nine genes were selected for reconfirmation; 40 genes were confirmed. Here we describe the siRNA screening strategy, assay implementation and validation, data triaging, and example genes of interest. The genes of interest include known and novel genes encoding secreted enzymes, proteases, G-protein-coupled receptors, metabolic enzymes, ion transporters, and proteins of unknown function. Repression of farnesyltransferase (FNTA) by siRNA and the enzyme inhibitor manumycin A caused elevation of ApoA-I secretion from hepatocytes and from transgenic mice expressing hApoA-I and cholesterol ester transfer protein transgenes. In total, this work underscores the power of functional genetic assessment to identify new therapeutic targets.

  8. Cholesterol Independent Suppression of Lymphocyte Activation, Autoimmunity and Glomerulonephritis by Apolipoprotein A-I in Normocholesterolemic Lupus-Prone Mice

    PubMed Central

    Black, Leland L.; Srivastava, Roshni; Schoeb, Trenton R.; Moore, Ray D.; Barnes, Stephen; Kabarowski, Janusz H.

    2015-01-01

    Apolipoprotein A-I (ApoA-I), the major lipid-binding protein of high-density lipoprotein (HDL), can prevent autoimmunity and suppress inflammation in hypercholesterolemic mice by attenuating lymphocyte cholesterol accumulation and removing tissue oxidized lipids. However, whether ApoA-I mediates immune suppressive or anti-inflammatory effects in normocholesterolemic conditions and the mechanisms involved remain unresolved. We transferred bone marrow from SLE-prone Sle123 mice into normal, ApoA-I knockout (ApoA-I−/−) and ApoA-I transgenic (ApoA-Itg) mice. Increased ApoA-I in ApoA-Itg mice suppressed CD4+ T and B cell activation without changing lymphocyte cholesterol levels or reducing major ApoA-I-binding oxidized fatty acids. Unexpectedly, oxidized fatty acid peroxisome proliferator-activated receptor gamma (PPARγ) ligands 13-hydroxyoctadecadienoic acid (HODE) and 9-HODE were increased in lymphocytes of autoimmune ApoA-Itg mice. ApoA-I reduced Th1 cells independently of changes in CD4+FoxP3+ regulatory T cells or CD11c+ dendritic cell activation and migration. Follicular helper T cells, germinal center B cells and autoantibodies were also lower in ApoA-Itg mice. Transgenic ApoA-I also improved SLE-mediated glomerulonephritis. However, ApoA-I deficiency did not have opposite effects on autoimmunity or glomerulonephritis, possibly due to compensatory increases of ApoE on HDL. We conclude that although compensatory mechanisms prevent pro-inflammatory effects of ApoA-I deficiency in normocholesterolemic mice, increasing ApoA-I can attenuate lymphocyte activation and autoimmunity in SLE independently of cholesterol transport, possibly through oxidized fatty acid PPARγ ligands, and can reduce renal inflammation in glomerulonephritis. PMID:26466956

  9. Effect of apolipoprotein a-I complex with tetrahydrocortisone on protein biosynthesis and glucose absorption by rat hepatocytes.

    PubMed

    Sumenkova, D V; Knyazev, R A; Guschya, R S; Polyakov, L M; Panin, L E

    2009-08-01

    We studied the effect of apolipoprotein A-I-tetrahydrocortisone complex on (14)C glucose absorption and lactate accumulation and on the rate of protein biosynthesis in isolated rat hepatocytes. The presence of apolipoprotein A-I-tetrahydrocortisone complex in the incubation medium increased absorption of labeled glucose by hepatocytes by 52%, while lactate content in the conditioning medium increased 4-fold. The rate of protein biosynthesis increased by 80% in comparison with control cells. It is hypothesized that the increase in protein biosynthesis rate in hepatocytes under the effect of apolipoprotein A-I-tetrahydrocortisone complex is due to stimulation of energy metabolism, specifically, of its glycolytic component.

  10. The 5A apolipoprotein A-I mimetic peptide displays anti-inflammatory and antioxidant properties in vivo and in vitro

    PubMed Central

    Tabet, Fatiha; Remaley, Alan T.; Segaliny, Aude I.; Millet, Jonathan; Yan, Ling; Nakhla, Shirley; Barter, Philip J.; Rye, Kerry-Anne; Lambert, Gilles

    2010-01-01

    Objectives The apolipoprotein (apo) A-I mimetic peptide 5A is highly specific for ABCA1-transporter mediated cholesterol efflux. We investigated whether the 5A peptide shares other beneficial features of apoA-I, such as protection against inflammation and oxidation. Methods New-Zealand White rabbits received an infusion of apoA-I, reconstituted HDL containing apoA-I ((A-I)rHDL) or the 5A peptide complexed with phospholipids (PLPC), prior to inserting a collar around the carotid artery. Human coronary artery endothelial cells (HCAECs) were incubated with (A-I)rHDL or 5A/PLPC prior to TNFa stimulation. Results ApoA-I, (A-I)rHDL and 5A/PLPC reduced the collar mediated increase in (i) endothelial expression of cell adhesion molecules VCAM-1 and ICAM-1, (ii) O2− production as well as the expression of the Nox4 catalytic subunits of the NADPH oxidase, and (iii) infiltration of circulating neutrophils into the carotid intima-media. In HCAECs, both 5A/PLPC and (A-I)rHDL inhibited TNFa induced ICAM-1 and VCAM-1 expression as well as the NF-κB signalling cascade and O2− production. The effects of the 5A/PLPC complex were no longer apparent in HCAECs knocked down for ABCA1. Conclusion Like apoA-I, the 5A peptide inhibits acute inflammation and oxidative stress in rabbit carotids and HCAECs. In vitro, the 5A peptide exerts these beneficial effects through interaction with ABCA1. PMID:19965776

  11. Folded functional lipid-poor apolipoprotein A-I obtained by heating of high-density lipoproteins: relevance to high-density lipoprotein biogenesis.

    PubMed

    Jayaraman, Shobini; Cavigiolio, Giorgio; Gursky, Olga

    2012-03-15

    HDL (high-density lipoproteins) remove cell cholesterol and protect from atherosclerosis. The major HDL protein is apoA-I (apolipoprotein A-I). Most plasma apoA-I circulates in lipoproteins, yet ~5% forms monomeric lipid-poor/free species. This metabolically active species is a primary cholesterol acceptor and is central to HDL biogenesis. Structural properties of lipid-poor apoA-I are unclear due to difficulties in isolating this transient species. We used thermal denaturation of human HDL to produce lipid-poor apoA-I. Analysis of the isolated lipid-poor fraction showed a protein/lipid weight ratio of 3:1, with apoA-I, PC (phosphatidylcholine) and CE (cholesterol ester) at approximate molar ratios of 1:8:1. Compared with lipid-free apoA-I, lipid-poor apoA-I showed slightly altered secondary structure and aromatic packing, reduced thermodynamic stability, lower self-associating propensity, increased adsorption to phospholipid surface and comparable ability to remodel phospholipids and form reconstituted HDL. Lipid-poor apoA-I can be formed by heating of either plasma or reconstituted HDL. We propose the first structural model of lipid-poor apoA-I which corroborates its distinct biophysical properties and postulates the lipid-induced ordering of the labile C-terminal region. In summary, HDL heating produces folded functional monomolecular lipid-poor apoA-I that is distinct from lipid-free apoA-I. Increased adsorption to phospholipid surface and reduced C-terminal disorder may help direct lipid-poor apoA-I towards HDL biogenesis.

  12. Anti-CD20 single chain variable antibody fragment-apolipoprotein A-I chimera containing nanodisks promote targeted bioactive agent delivery to CD20-positive lymphomas.

    PubMed

    Crosby, Natasha M; Ghosh, Mistuni; Su, Betty; Beckstead, Jennifer A; Kamei, Ayako; Simonsen, Jens B; Luo, Bing; Gordon, Leo I; Forte, Trudy M; Ryan, Robert O

    2015-08-01

    A fusion protein comprising an α-CD20 single chain variable fragment (scFv) antibody, a spacer peptide, and human apolipoprotein (apo) A-I was constructed and expressed in Escherichia coli. The lipid interaction properties intrinsic to apoA-I as well as the antigen recognition properties of the scFv were retained by the chimera. scFv•apoA-I was formulated into nanoscale reconstituted high-density lipoprotein particles (termed nanodisks; ND) and incubated with cultured cells. α-CD20 scFv•apoA-I ND bound to CD20-positive non-Hodgkins lymphoma (NHL) cells (Ramos and Granta) but not to CD20-negative T lymphocytes (i.e., Jurkat). Binding to NHL cells was partially inhibited by pre-incubation with rituximab, a monoclonal antibody directed against CD20. Confocal fluorescence microscopy analysis of Granta cells following incubation with α-CD20 scFv•apoA-I ND formulated with the intrinsically fluorescent hydrophobic polyphenol, curcumin, revealed α-CD20 scFv•apoA-I localizes to the cell surface, while curcumin off-loads and gains entry to the cell. Compared to control incubations, viability of cultured NHL cells was decreased upon incubation with α-CD20 scFv•apoA-I ND harboring curcumin. Thus, formulation of curcumin ND with α-CD20 scFv•apoA-I as the scaffold component confers cell targeting and enhanced bioactive agent delivery, providing a strategy to minimize toxicity associated with chemotherapeutic agents.

  13. International Federation of Clinical Chemistry standardization project for measurements of apolipoproteins A-I and B. IV. Comparability of apolipoprotein B values by use of International Reference Material.

    PubMed

    Marcovina, S M; Albers, J J; Kennedy, H; Mei, J V; Henderson, L O; Hannon, W H

    1994-04-01

    We performed temporal and thermal stability studies on SP3-07, a liquid-stabilized reference material for apolipoprotein (apo) B, selected during the previous phase of the International Federation of Clinical Chemistry project on standardization of apolipoprotein measurements. Results indicate that SP3-07 stored at -70 degrees C has the long-term stability required for a reference material. We assigned an accuracy-based apo B value of 1.22 g/L to SP3-07, using a nephelometric method that was calibrated with freshly isolated low-density lipoprotein for which the apo B mass value was determined by a standardized sodium dodecyl sulfate-Lowry procedure. Using a common protocol, the study participants transferred the assigned mass value from SP3-07 to the individual calibrators of the analytical systems and measured the apo B concentration of 20 fresh-frozen samples obtained from individual donors and covering a clinically relevant range of apo B values. The among-laboratory CV on these samples, analyzed by 25 analytical systems, ranged from 3.1% to 6.7%. These results demonstrate the lack of matrix effects of SP3-07 and its ability to provide accurate and comparable apo B values in a variety of immunochemical methods. On the basis of the outcome of these studies, the World Health Organization has endorsed SP3-07 as the International Reference Material for Apolipoprotein B.

  14. Composition, structure and substrate properties of reconstituted discoidal HDL with apolipoprotein A-I and cholesteryl ester

    NASA Astrophysics Data System (ADS)

    Dergunov, Alexander D.; Shabrova, Elena V.; Dobretsov, Gennady E.

    2010-03-01

    To investigate the influence of lipid unsaturation and neutral lipid on the maturation of high density lipoproteins, the discoidal complexes of apoA-I, phosphatidylcholine and cholesteryl ester (CE) were prepared. Saturated dipalmitoylphosphatidylcholine (DPPC) and unsaturated palmitoyllinoleoylphosphatidylcholine (PLPC), palmitoyloleoylphosphatidylcholine (POPC), and fluorescent probe cholesteryl 1-pyrenedecanoate (CPD) that forms in a diffusion- and concentration-dependent manner short-lived dimer of unexcited and excited molecules (excimer) were used. The apoA-I/DPPC/CPD complexes were heterogeneous by size, composition and probe location. CPD molecules incorporated more efficiently into larger complexes and accumulated in a central part of the discs. The apoA-I/POPC(PLPC)/CPD were also heterogeneous, however, probe molecules distributed preferentially into smaller complexes and accumulated at disc periphery. The kinetics of CPD transfer by recombinant cholesteryl ester transfer protein (CETP) to human plasma LDL is well described by two-exponential decay, the fast component with a shorter transfer time being more populated in PLPC compared to DPPC complexes. The presence of CE molecules in discoidal HDL results in particle heterogeneity. ApoA-I influences the CETP activity modulating the properties of apolipoprotein-phospholipid interface. This may include CE molecules accumulation in the boundary lipid in unsaturated phosphatidylcholine and cluster formation in the bulk bilayer in saturated phosphatidylcholine.

  15. Phylogenetic distribution of apolipoproteins A-I and E in vertebrates as determined by Western blot analysis.

    PubMed

    Duggan, A E; Callard, I P

    2001-08-01

    A putative apolipoprotein E (apoE) has been identified in the HDL and VHDL fractions of the turtle. This observation is of particular interest considering apoE has been reported absent in the domestic hen (Hermier et al., '95; Biochim Biophys Acta: 105-118, 1995) and thus presumed absent in nonmammalian vertebrates altogether. As a result, partial amino acid sequencing of this protein was performed and revealed that one fragment shared 41% sequence identity to human apoE. Western blot analysis using antisera to apoE demonstrated cross-reactivity to a 34-kDa protein (putative apoE) in turtle plasma. Further investigation using anti-apoE antibody in Western blot analysis detected immunoreactive apoE in the plasma of lamprey, spiny dogfish, skate, and alligator, but not in flounder, newt or python; its absence in several species of birds was confirmed. Using anti-apoA-I antibody, apoA-I was detected in all vertebrate groups except a representative teleost (flounder). Apo-A-I antibody cross-reacted weakly with some putative apoE proteins (chicken, spiny dogfish and skate) and the reverse was true for anti-apoE, which cross-reacted with putative apoA-I in birds, reptiles, and elasmobranchs, confirming the molecular similarity and phylogenetic relatedness of these two proteins.

  16. Serum Apolipoprotein A-I and Large High-Density Lipoprotein Particles Are Positively Correlated with FEV1 in Atopic Asthma

    PubMed Central

    Kaler, Maryann; Cuento, Rosemarie A.; Gordon, Elizabeth M.; Weir, Nargues A.; Sampson, Maureen; Fontana, Joseph R.; MacDonald, Sandra; Moss, Joel; Manganiello, Vincent; Remaley, Alan T.; Levine, Stewart J.

    2015-01-01

    Rationale: Although lipids, apolipoproteins, and lipoprotein particles are important modulators of inflammation, varying relationships exist between these parameters and asthma. Objectives: To determine whether serum lipids and apolipoproteins correlate with the severity of airflow obstruction in subjects with atopy and asthma. Methods: Serum samples were obtained from 154 atopic and nonatopic subjects without asthma, and 159 subjects with atopy and asthma. Serum lipid and lipoprotein levels were quantified using standard diagnostic assays and nuclear magnetic resonance (NMR) spectroscopy. Airflow obstruction was assessed by FEV1% predicted. Measurements and Main Results: Serum lipid levels correlated with FEV1 only in the subjects with atopy and asthma. Serum levels of high-density lipoprotein (HDL) cholesterol and apolipoprotein A-I (apoA-I) were positively correlated with FEV1 in subjects with atopy and asthma, whereas a negative correlation existed between FEV1 and serum levels of triglycerides, low-density lipoprotein (LDL) cholesterol, apolipoprotein B (apoB), and the apoB/apoA-I ratio. NMR spectroscopy identified a positive correlation between FEV1 and HDLNMR particle size, as well as the concentrations of large HDLNMR particles and total IDLNMR (intermediate-density lipoprotein) particles in subjects with atopy and asthma. In contrast, LDLNMR particle size and concentrations of LDLNMR and VLDLNMR (very-low-density lipoprotein) particles were negatively correlated with FEV1 in subjects with atopy and asthma. Conclusions: In subjects with atopy and asthma, serum levels of apoA-I and large HDLNMR particles are positively correlated with FEV1, whereas serum triglycerides, LDL cholesterol, and apoB are associated with more severe airflow obstruction. These results may facilitate future studies to assess whether apoA-I and large HDLNMR particles can reduce airflow obstruction and disease severity in asthma. PMID:25692941

  17. Single nucleotide polymorphisms of APOA1 gene and their relationship with serum apolipoprotein A-I concentrations in the native population of Assam

    PubMed Central

    Bora, Kaustubh; Pathak, Mauchumi Saikia; Borah, Probodh; Hussain, Md. Iftikar; Das, Dulmoni

    2015-01-01

    Background There is a growing interest in the role of allelic variants of the APOA1 gene in relation to a number of disorders. We described two common polymorphisms of the APOA1 gene, G-75A and C+83T and investigated their potential influence on the serum apolipoprotein A-I (apo A-I) levels in the native population of Assam — a region that is ethnically distinct and from where no information is hitherto available. Methods Blood samples were collected from 150 healthy volunteers. Apo A-I levels were estimated by immunoturbidometry. Genotyping was done by a PCR-RFLP method that involved DNA extraction from whole blood, followed by polymerase chain reaction and digestion of the PCR product by MspI restriction enzyme, and analysis of fragment sizes in 12% polyacrylamide gel. Results The GG variant at G-75A locus and CC variant at C+83T locus were the most prevalent. GG/CC was the most common combination. Homozygous TT genotype was not detected in any of the subjects. The rare allele frequencies for the G-75A and C+83T sites were found to be 0.22 and 0.06 respectively, which significantly differed from those reported in some other populations in neighbouring regions. Serum apo A-I concentrations did not vary significantly across the detected genotypes. These findings were consistent in both sexes. Conclusion We described the distribution of the G-75A and C+83T polymorphisms of the APOA1 gene in the population of Assam for the first time. These polymorphisms were not found to directly influence apo A-I concentrations in this population either individually or synergistically. PMID:26702398

  18. A human apolipoprotein E mimetic peptide reduces atherosclerosis in aged apolipoprotein E null mice

    PubMed Central

    Xu, Yanyong; Liu, Hongmei; Liu, Mengting; Li, Feifei; Liu, Liangchen; Du, Fen; Fan, Daping; Yu, Hong

    2016-01-01

    Apolipoprotein E (apoE) is well known as an antiatherogenic protein via regulating lipid metabolism and inflammation. We previously reported that a human apoE mimetic peptide, EpK, reduced atherosclerosis in apoE null (apoE-/-) mice through reducing inflammation without affecting plasma lipid levels. Here, we construct another human apoE mimetic peptide, named hEp, and investigate whether expression of hEp can reduce atherosclerotic lesion development in aged female apoE-/- mice with pre-existing lesions. We found that chemically synthesized hEp significantly decreased cholesterol accumulation induced by oxidized low density lipoprotein and the expression of inflammatory cytokines TNFα and IL-6 induced by lipopolysaccharide in macrophages. In an in vivo study, Lv-hEp-GFP lentiviruses were intravenously injected into 9 month-old apoE-/- mice. Mice were then fed a chow diet for 18 weeks. Results showed that in comparison to the Lv-GFP lentivirus injection (Lv-GFP) group, Lv-hEp-GFP lentivirus injection achieved hepatic hEp expression and secretion in apoE-/- mice. It was observed that hEp expression significantly reduced plasma VLDL and LDL cholesterol levels and decreased aortic atherosclerotic lesions. This was accompanied by an increase of LDL receptor expression and a reduction of TNFα and IL-6 mRNA levels in the liver. Moreover, expression of hEp increased plasma paraoxonase-1 activity and decreased plasma myeloperoxidase activity and serum amyloid A levels. Our study provides evidence that hEp may be developed as a promising therapeutic apoE mimetic peptide for atherosclerosis-related cardiovascular diseases through its induction of plasma VLDL/LDL cholesterol clearance as well as its anti-oxidative and anti-inflammatory activities. PMID:27648138

  19. The intrinsic factor-vitamin B12 receptor, cubilin, is a high-affinity apolipoprotein A-I receptor facilitating endocytosis of high-density lipoprotein.

    PubMed

    Kozyraki, R; Fyfe, J; Kristiansen, M; Gerdes, C; Jacobsen, C; Cui, S; Christensen, E I; Aminoff, M; de la Chapelle, A; Krahe, R; Verroust, P J; Moestrup, S K

    1999-06-01

    Cubilin is the intestinal receptor for the endocytosis of intrinsic factor-vitamin B12. However, several lines of evidence, including a high expression in kidney and yolk sac, indicate it may have additional functions. We isolated apolipoprotein A-I (apoA-I), the main protein of high-density lipoprotein (HDL), using cubilin affinity chromatography. Surface plasmon resonance analysis demonstrated a high-affinity binding of apoA-I and HDL to cubilin, and cubilin-expressing yolk sac cells showed efficient 125I-HDL endocytosis that could be inhibited by IgG antibodies against apoA-I and cubilin. The physiological relevance of the cubilin-apoA-I interaction was further emphasized by urinary apoA-I loss in some known cases of functional cubilin deficiency. Therefore, cubilin is a receptor in epithelial apoA-I/HDL metabolism.

  20. Concomitant Effects of Ramadan Fasting and Time-Of-Day on Apolipoprotein AI, B, Lp-a and Homocysteine Responses during Aerobic Exercise in Tunisian Soccer Players

    PubMed Central

    Hammouda, Omar; Chtourou, Hamdi; Aloui, Asma; Chahed, Henda; Kallel, Choumous; Miled, Abdelhedi; Chamari, Karim; Chaouachi, Anis; Souissi, Nizar

    2013-01-01

    Objective To examine the time-of-day and Ramadan fasting (RF) effects on serum apolipoprotein-AI (Apo-AI) and B (Apo-B), lipoprotein particles-a (Lp-a), high-sensitive C-reactive-protein (hs-CRP), and homocysteine (Hcy) during the Yo-Yo intermittent recovery test (YYIRT). Design Performance and biochemical measures were completed at two times-of-day (07:00 and 17:00 h), 1-week before RF (BR), the second week of RF (SWR), and the fourth week of RF (ER). Setting For each session, subjects performed the YYIRT, and blood samples were taken before and 3-min after the test for biochemical measures. Participants Fifteen soccer players. Main Outcome Measures Total distance during the YYIRT, core temperature, body composition, dietary intakes, lipid (HDL-C, LDL-C, Apo-AI, B and Lp-a) and inflammatory (hs-CRP and Hcy) profiles. Results Performances during the YYIRT were higher in the evening than the morning BR (P < 0.05), but this fluctuation was not observed during RF. Moreover, LDL-C, ApoB, and Lp-a were stable throughout the daytime BR. However, during RF, they decreased at 17:00 h (P < 0.05). Likewise, HDL-C and Apo-AI increased after the exercise and were higher at 17:00 h BR (P < 0.001). Moreover, these parameters increased during RF (P < 0.01). Furthermore, Hcy and hs-CRP increased during the exercise (P < 0.01) with higher evening levels BR. During ER, the diurnal pattern of Hcy was inversed (P < 0.001). Conclusions This study concluded that caloric restriction induced by RF seems to ameliorate lipid and inflammatory markers of cardiovascular health during intermittent exercise performed in the evening. PMID:24244572

  1. Human apolipoprotein E expression in Escherichia coli: structural and functional identity of the bacterially produced protein with plasma apolipoprotein E.

    PubMed Central

    Vogel, T; Weisgraber, K H; Zeevi, M I; Ben-Artzi, H; Levanon, A Z; Rall, S C; Innerarity, T L; Hui, D Y; Taylor, J M; Kanner, D

    1985-01-01

    Human apolipoprotein E (apoE) was produced in Escherichia coli by transforming cells with an expression vector containing a reconstructed apoE cDNA, a lambda PL promoter regulated by the thermolabile cI repressor, and a ribosomal binding site derived from the lambda cII or the E. coli beta-lactamase gene. Transformed cells induced at 42 degrees C for short periods of time (less than 20 min) produced apoE, which accumulated in the cells at levels of approximately equal to 1% of the total soluble cellular protein. Longer induction periods resulted in cell lysis and the proteolytic destruction of apoE. The bacterially produced apoE was purified by heparin-Sepharose affinity chromatography, Sephacryl S-300 gel filtration, and preparative Immobiline isoelectric focusing. The final yield was approximately equal to 20% of the initial apoE present in the cells. Except for an additional methionine at the amino terminus, the bacterially produced apoE was indistinguishable from authentic human plasma apoE as determined by NaDodSO4 and isoelectric focusing gel electrophoresis, amino acid composition of the total protein as well as its cyanogen bromide fragments, and partial amino acid sequence analysis (residues 1-17 and 109-164). Both the bacterially produced and authentic plasma apoE bound similarly to apolipoprotein B,E(low density lipoprotein) receptors of human fibroblasts and to hepatic apoE receptors. Intravenous injection resulted in similar rates of clearance for both the bacterially produced and authentic apoE from rabbit and rat plasma (approximately equal to 50% removed in 20 min). The ability to synthesize a bacterially produced human apolipoprotein with biological properties indistinguishable from those of the native protein will allow the production of large quantities of apoE for use in further investigations of the biological and physiological properties of this apolipoprotein. Images PMID:3909150

  2. Apolipoprotein E promotes lipid accumulation and differentiation in human adipocytes

    SciTech Connect

    Lasrich, Dorothee; Bartelt, Alexander; Grewal, Thomas; Heeren, Joerg

    2015-09-10

    Several studies in mice indicate a role for apolipoprotein E (APOE) in lipid accumulation and adipogenic differentiation in adipose tissue. However, little is yet known if APOE functions in a similar manner in human adipocytes. This prompted us to compare lipid loading and expression of adipocyte differentiation markers in APOE-deficient and control adipocytes using the differentiated human mesenchymal stem cell line hMSC-Tert as well as primary human and mouse adipocytes as model systems. Differentiated hMSC-Tert were stably transduced with or without siRNA targeting APOE while murine adipocytes were isolated from wild type and Apoe knockout mice. Human APOE knockdown hMSC-Tert adipocytes accumulated markedly less triglycerides compared to control cells. This correlated with strongly decreased gene expression levels of adipocyte markers such as adiponectin (ADIPOQ) and fatty acid binding protein 4 (FABP4) as well as the key transcription factor driving adipocyte differentiation, peroxisome proliferator activator receptor gamma (PPARG), in particular the PPARG2 isoform. Similarly, differentiation of murine Apoe-deficient adipocytes was characterized by reduced gene expression of Adipoq, Fabp4 and Pparg. Interestingly, incubation of APOE-deficient hMSC-Tert adipocytes with conditioned media from APOE3-overexpressing adipocytes or APOE-containing Very Low Density Lipoprotein (VLDL) partially restored triglyceride accumulation, but were unable to induce adipocyte differentiation, as judged by expression of adipocyte markers. Taken together, depletion of endogenous APOE in human adipocytes severely impairs lipid accumulation, which is associated with an inability to initiate differentiation. - Highlights: • Immortalized human mesenchymal stem cells were used to study adipocyte development. • Knockdown of endogenous APOE lead to impaired lipid accumulation and adipogenesis. • APOE supplementation partially restored lipid accumulation but not differentiation.

  3. Distinct Hepatic Receptors for Low Density Lipoprotein and Apolipoprotein E in Humans

    NASA Astrophysics Data System (ADS)

    Hoeg, Jeffrey M.; Demosky, Stephen J.; Gregg, Richard E.; Schaefer, Ernst J.; Brewer, H. Bryan

    1985-02-01

    Since the liver is a central organ for lipid and lipoprotein synthesis and catabolism, hepatic receptors for specific apolipoproteins on plasma lipoproteins would be expected to modulate lipid and lipoprotein metabolism. The role of hepatic receptors for low density lipoproteins and apolipoprotein E-containing lipoproteins was evaluated in patients with complementary disorders in lipoprotein metabolism: abetalipoproteinemia and homozygous familial hypercholesterolemia. In addition, hepatic membranes from a patient with familial hypercholesterolemia were studied and compared before and after portacaval shunt surgery. The results establish that the human liver has receptors for apolipoproteins B and E. Furthermore, in the human, hepatic receptors for low density lipoproteins and apolipoprotein E are genetically distinct and can undergo independent control.

  4. Cholesterol Efflux Capacity of Apolipoprotein A-I Varies with the Extent of Differentiation and Foam Cell Formation of THP-1 Cells

    PubMed Central

    Yano, Kouji; Sato, Megumi; Yoshimoto, Akira; Ichimura, Naoya; Kameda, Takahiro; Kubota, Tetsuo

    2016-01-01

    Apolipoprotein A-I (apoA-I), the main protein component of high-density lipoprotein (HDL), has many protective functions against atherosclerosis, one of them being cholesterol efflux capacity. Although cholesterol efflux capacity measurement is suggested to be a key biomarker for evaluating the risk of development of atherosclerosis, the assay has not been optimized till date. This study aims at investigating the effect of different states of cells on the cholesterol efflux capacity. We also studied the effect of apoA-I modification by homocysteine, a risk factor for atherosclerosis, on cholesterol efflux capacity in different states of cells. The cholesterol efflux capacity of apoA-I was greatly influenced by the extent of differentiation of THP-1 cells and attenuated by excessive foam cell formation. N-Homocysteinylated apoA-I indicated a lower cholesterol efflux capacity than normal apoA-I in the optimized condition, whereas no significant difference was observed in the cholesterol efflux capacity between apoA-I in the excessive cell differentiation or foam cell formation states. These results suggest that cholesterol efflux capacity of apoA-I varies depending on the state of cells. Therefore, the cholesterol efflux assay should be performed using protocols optimized according to the objective of the experiment. PMID:27957343

  5. An Evaluation of the Crystal Structure of C-terminal Truncated Apolipoprotein A-I in Solution Reveals Structural Dynamics Related to Lipid Binding*

    PubMed Central

    Melchior, John T.; Walker, Ryan G.; Morris, Jamie; Jones, Martin K.; Segrest, Jere P.; Lima, Diogo B.; Carvalho, Paulo C.; Gozzo, Fábio C.; Castleberry, Mark; Thompson, Thomas B.; Davidson, W. Sean

    2016-01-01

    Apolipoprotein (apo) A-I mediates many of the anti-atherogenic functions attributed to high density lipoprotein. Unfortunately, efforts toward a high resolution structure of full-length apoA-I have not been fruitful, although there have been successes with deletion mutants. Recently, a C-terminal truncation (apoA-IΔ185–243) was crystallized as a dimer. The structure showed two helical bundles connected by a long, curved pair of swapped helical domains. To compare this structure to that existing under solution conditions, we applied small angle x-ray scattering and isotope-assisted chemical cross-linking to apoA-IΔ185–243 in its dimeric and monomeric forms. For the dimer, we found evidence for the shared domains and aspects of the N-terminal bundles, but not the molecular curvature seen in the crystal. We also found that the N-terminal bundles equilibrate between open and closed states. Interestingly, this movement is one of the transitions proposed during lipid binding. The monomer was consistent with a model in which the long shared helix doubles back onto the helical bundle. Combined with the crystal structure, these data offer an important starting point to understand the molecular details of high density lipoprotein biogenesis. PMID:26755744

  6. Specific Regional Transcription of Apolipoprotein E in Human Brain Neurons

    PubMed Central

    Xu, Pu-Ting; Gilbert, John R.; Qiu, Hui-Ling; Ervin, John; Rothrock-Christian, Tracie R.; Hulette, Christine; Schmechel, Donald E.

    1999-01-01

    In central nervous system injury and disease, apolipoprotein E (APOE, gene; apoE, protein) might be involved in neuronal injury and death indirectly through extracellular effects and/or more directly through intracellular effects on neuronal metabolism. Although intracellular effects could clearly be mediated by neuronal uptake of extracellular apoE, recent experiments in injury models in normal rodents and in mice transgenic for the human APOE gene suggest the additional possibility of intraneuronal synthesis. To examine whether APOE might be synthesized by human neurons, we performed in situ hybridization on paraffin-embedded and frozen brain sections from three nondemented controls and five Alzheimer’s disease (AD) patients using digoxigenin-labeled antisense and sense cRNA probes to human APOE. Using the antisense APOE probes, we found the expected strong hybridization signal in glial cells as well as a generally fainter signal in selected neurons in cerebral cortex and hippocampus. In hippocampus, many APOE mRNA-containing neurons were observed in sectors CA1 to CA4 and the granule cell layer of the dentate gyrus. In these regions, APOE mRNA containing neurons could be observed adjacent to nonhybridizing neurons of the same cell class. APOE mRNA transcription in neurons is regionally specific. In cerebellar cortex, APOE mRNA was seen only in Bergmann glial cells and scattered astrocytes but not in Purkinje cells or granule cell neurons. ApoE immunocytochemical localization in semi-adjacent sections supported the selectivity of APOE transcription. These results demonstrate the expected result that APOE mRNA is transcribed and expressed in glial cells in human brain. The important new finding is that APOE mRNA is also transcribed and expressed in many neurons in frontal cortex and human hippocampus but not in neurons of cerebellar cortex from the same brains. This regionally specific human APOE gene expression suggests that synthesis of apoE might play a role

  7. Modified apolipoprotein (apo) A-I by artificial sweetener causes severe premature cellular senescence and atherosclerosis with impairment of functional and structural properties of apoA-I in lipid-free and lipid-bound state.

    PubMed

    Jang, Wookju; Jeoung, Nam Ho; Cho, Kyung-Hyun

    2011-05-01

    Long-term consumption of artificial sweeteners (AS) has been the recent focus of safety concerns. However, the potential risk of the AS in cardiovascular disease and lipoprotein metabolism has not been investigated sufficiently. We compared the influence of AS (aspartame, acesulfame K, and saccharin) and fructose in terms of functional and structural correlations of apolipoprotein (apo) A-I and high-density lipoproteins (HDL), which have atheroprotective effects. Long-term treatment of apoA-I with the sweetener at physiological concentration (3 mM for 168 h) resulted in loss of antioxidant and phospholipid binding activities with modification of secondary structure. The AS treated apoA-I exhibited proteolytic cleavage to produce 26 kDa-fragment. They showed pro-atherogenic properties in acetylated LDL phagocytosis of macrophages. Each sweetener alone or sweetener-treated apoA-I caused accelerated senescence in human dermal fibroblasts. These results suggest that long-term consumption of AS might accelerate atherosclerosis and senescence via impairment of function and structure of apoA-I and HDL.

  8. Heparin and Methionine Oxidation Promote the Formation of Apolipoprotein A-I Amyloid Comprising α-Helical and β-Sheet Structures.

    PubMed

    Townsend, David; Hughes, Eleri; Hussain, Rohanah; Siligardi, Giuliano; Baldock, Sarah; Madine, Jillian; Middleton, David A

    2017-03-13

    Peptides derived from apolipoprotein A-I (apoA-I), the main component of high-density lipoprotein (HDL), constitute the main component of amyloid deposits that colocalize with atherosclerotic plaques. Here we investigate the molecular details of full-length, lipid-deprived apoA-I after assembly into insoluble aggregates under physiologically relevant conditions known to induce aggregation in vitro. Unmodified apoA-I is shown to remain soluble at pH 7 for at least 3 days, retaining its native α-helical-rich structure. Upon acidification to pH 4, apoA-I rapidly assembles into insoluble nonfibrillar aggregates lacking the characteristic cross-β features of amyloid. In the presence of heparin, the rate and thioflavin T responsiveness of the aggregates formed at pH 4 increase and short amyloid-like fibrils are observed, which give rise to amyloid-characteristic X-ray reflections at 4.7 and 10 Å. Solid-state nuclear magnetic resonance (SSNMR) and synchrotron radiation circular dichroism spectroscopy of fibrils formed in the presence of heparin show they retain some α-helical characteristics together with new β-sheet structures. Interestingly, SSNMR indicates a similar molecular structure of aggregates formed in the absence of heparin at pH 6 after oxidation of the three methionine residues, although their morphology is rather different from that of the heparin-derived fibrils. We propose a model for apoA-I aggregation in which perturbations of a four-helix bundle-like structure, induced by interactions of heparin or methionine oxidation, cause the partially helical N-terminal residues to disengage from the remaining, intact helices, thereby allowing self-assembly via β-strand associations.

  9. ITRAQ-based quantitative proteomics reveals apolipoprotein A-I and transferrin as potential serum markers in CA19-9 negative pancreatic ductal adenocarcinoma

    PubMed Central

    Lin, Chao; Wu, Wen-Chuan; Zhao, Guo-Chao; Wang, Dan-Song; Lou, Wen-Hui; Jin, Da-Yong

    2016-01-01

    Abstract Currently the diagnosis of pancreatic ductal adenocarcinoma (PDAC) relies on CA19-9 and radiological means, whereas some patients do not have elevated levels of CA19-9 secondary to pancreatic cancer. The purpose of this study was to identify potential serum biomarkers for CA19-9 negative PDAC. A total of 114 serum samples were collected from 3 groups: CA19-9 negative PDAC patients (n = 34), CA19-9 positive PDAC patients (n = 44), and healthy volunteers (n = 36), whereas the first 12 samples from each group were used for isobaric tags for relative and absolute quantitation (iTRAQ) analysis. Thereafter, candidate biomarkers were selected for validation by enzyme-linked immunosorbent assay (ELISA) with the rest specimens. Using the iTRAQ approach, a total of 5 proteins were identified as significantly different between CA19-9 negative PDAC patients and healthy subjects according to our defined criteria. Apolipoprotein A-I (APOA-I) and transferrin (TF) were selected to validate the proteomic results by ELISA in a further 78 serum specimens. It revealed that TF significantly correlated with the degree of histological differentiation (P = 0.042), and univariate and multivariate analyses indicated that TF is an independent prognostic factor for survival (hazard ratio, 0.302; 95% confidence interval, 0.118–0.774; P = 0.013) of patients with PDAC after curative surgery. ITRAQ-based quantitative proteomics revealed that APOA-I and TF may be potential CA19-9 negative PDAC serum markers. PMID:27495108

  10. Stimulation of Hepatic Apolipoprotein A-I Production by Novel Thieno-Triazolodiazepines: Roles of the Classical Benzodiazepine Receptor, PAF Receptor, and Bromodomain Binding

    PubMed Central

    Kempen, Herman J; Bellus, Daniel; Fedorov, Oleg; Nicklisch, Silke; Filippakopoulos, Panagis; Picaud, Sarah; Knapp, Stefan

    2013-01-01

    Expression and secretion of apolipoprotein A-I (apoA-I) by cultured liver cells can be markedly stimulated by triazolodiazepines (TZDs). It has been shown previously that the thieno-TZD Ro 11-1464 increases plasma levels of apoA-I and in vivomacrophage reverse cholesterol transport in mice. However, these effects were only seen at high doses, at which the compound could act on central benzodiazepine (BZD) receptors or platelet activating factor (PAF) receptors, interfering with its potential utility. In this work, we describe 2 new thieno-TZDs MDCO-3770 and MDCO-3783, both derived from Ro 11-1464. These compounds display the same high efficacy on apoA-I production, metabolic stability, and lack of cytotoxicity in cultured hepatocytes as Ro 11-1464, but they do not bind to the central BZD receptor and PAF receptor. The quinazoline RVX-208 was less efficacious in stimulating apoA-I production and displayed signs of cytotoxicity. Certain TZDs stimulating apoA-I production are now known to be inhibitors of bromodomain (BRD) extra-terminal (BET) proteins BRDT, BRD2, BRD3, and BRD4, and this inhibition was inferred as a main molecular mechanism for their effect on apoA-I expression. We show here that the thieno-TZD (+)-JQ1, a potent BET inhibitor, strongly stimulated apoA-I production in Hep-G2 cells, but that its enantiomer (−)-JQ1, which has no BET inhibitor activity, also showed considerable effect on apoA-I production. MDCO-3770 and MDCO-3783 also inhibited BRD3 and BRD4 in vitro, with potency somewhat below that of (+)-JQ1. We conclude that the effect of thieno-TZDs on apoA-I expression is not due to inhibition of the BZD or PAF receptors and is not completely explained by transcriptional repression by BET proteins. PMID:25278768

  11. Stimulation of Hepatic Apolipoprotein A-I Production by Novel Thieno-Triazolodiazepines: Roles of the Classical Benzodiazepine Receptor, PAF Receptor, and Bromodomain Binding.

    PubMed

    Kempen, Herman J; Bellus, Daniel; Fedorov, Oleg; Nicklisch, Silke; Filippakopoulos, Panagis; Picaud, Sarah; Knapp, Stefan

    2013-01-01

    Expression and secretion of apolipoprotein A-I (apoA-I) by cultured liver cells can be markedly stimulated by triazolodiazepines (TZDs). It has been shown previously that the thieno-TZD Ro 11-1464 increases plasma levels of apoA-I and in vivomacrophage reverse cholesterol transport in mice. However, these effects were only seen at high doses, at which the compound could act on central benzodiazepine (BZD) receptors or platelet activating factor (PAF) receptors, interfering with its potential utility. In this work, we describe 2 new thieno-TZDs MDCO-3770 and MDCO-3783, both derived from Ro 11-1464. These compounds display the same high efficacy on apoA-I production, metabolic stability, and lack of cytotoxicity in cultured hepatocytes as Ro 11-1464, but they do not bind to the central BZD receptor and PAF receptor. The quinazoline RVX-208 was less efficacious in stimulating apoA-I production and displayed signs of cytotoxicity. Certain TZDs stimulating apoA-I production are now known to be inhibitors of bromodomain (BRD) extra-terminal (BET) proteins BRDT, BRD2, BRD3, and BRD4, and this inhibition was inferred as a main molecular mechanism for their effect on apoA-I expression. We show here that the thieno-TZD (+)-JQ1, a potent BET inhibitor, strongly stimulated apoA-I production in Hep-G2 cells, but that its enantiomer (-)-JQ1, which has no BET inhibitor activity, also showed considerable effect on apoA-I production. MDCO-3770 and MDCO-3783 also inhibited BRD3 and BRD4 in vitro, with potency somewhat below that of (+)-JQ1. We conclude that the effect of thieno-TZDs on apoA-I expression is not due to inhibition of the BZD or PAF receptors and is not completely explained by transcriptional repression by BET proteins.

  12. Kinetic and thermodynamic analyses of spontaneous exchange between high-density lipoprotein-bound and lipid-free apolipoprotein A-I.

    PubMed

    Handa, Daisuke; Kimura, Hitoshi; Oka, Tatsuya; Takechi, Yuki; Okuhira, Keiichiro; Phillips, Michael C; Saito, Hiroyuki

    2015-02-03

    It is thought that apolipoprotein A-I (apoA-I) spontaneously exchanges between high-density lipoprotein (HDL)-bound and lipid-free states, which is relevant to the occurrence of preβ-HDL particles in plasma. To improve our understanding of the mechanistic basis for this phenomenon, we performed kinetic and thermodynamic analyses for apoA-I exchange between discoidal HDL-bound and lipid-free forms using fluorescence-labeled apoA-I variants. Gel filtration experiments demonstrated that addition of excess lipid-free apoA-I to discoidal HDL particles promotes exchange of apoA-I between HDL-associated and lipid-free pools without alteration of the steady-state HDL particle size. Kinetic analysis of time-dependent changes in NBD fluorescence upon the transition of NBD-labeled apoA-I from HDL-bound to lipid-free state indicates that the exchange kinetics are independent of the collision frequency between HDL-bound and lipid-free apoA-I, in which the lipid binding ability of apoA-I affects the rate of association of lipid-free apoA-I with the HDL particles and not the rate of dissociation of HDL-bound apoA-I. Thus, C-terminal truncations or mutations that reduce the lipid binding affinity of apoA-I strongly impair the transition of lipid-free apoA-I to the HDL-bound state. Thermodynamic analysis of the exchange kinetics demonstrated that the apoA-I exchange process is enthalpically unfavorable but entropically favorable. These results explain the thermodynamic basis of the spontaneous exchange reaction of apoA-I associated with HDL particles. The altered exchangeability of dysfunctional apoA-I would affect HDL particle rearrangement, leading to perturbed HDL metabolism.

  13. The secondary structure of apolipoproteins in human HDL3 particles after chemical modification of their tyrosine, lysine, cysteine or arginine residues. A Fourier transform infrared spectroscopy study.

    PubMed

    Herzyk, E; Owen, J S; Chapman, D

    1988-09-02

    Fourier transform infrared spectra of apolipoprotein E-depleted human HDL3 have been obtained in H2O and 2H2O buffers. The absorption bands in the protein amide I and amide II regions (1700-1500 cm-1) were assigned to alpha-helical, disordered and beta-strand/beta-turn structures of apolipoproteins A-I and A-II (apoA-I and apoA-II), the apolipoprotein constituents of HDL3. Modification of HDL3 by tetranitromethane (TNM) treatment, acetylation, reduction plus alkylation and 1,2-cyclohexanedione treatment derivatised tyrosine, lysine, cysteine and arginine residues, respectively, and caused alteration of the secondary structure of the HDL3 apolipoproteins to different extents. Each of the chemical modifications caused changes in the frequency of bands associated with beta-strands/beta-turns, but only TNM treatment of HDL3, as judged by the second- and fourth-derivative spectra, resulted in a shift of the band assigned to the alpha-helical structure of the proteins. In agreement with other workers, only TNM treatment of HDL3 particles was found to inhibit their binding by high-affinity cell membrane receptors. It is proposed, therefore, that receptor recognition of HDL3 particles is dependent on conservation of the alpha-helix structures within apoA-I and apoA-II, and that beta-strand/beta-turn structures are not involved. This conclusion is consistent with the predominance of amphipathic alpha-helical structures in both apolipoproteins and with the relaxed specificity of the receptors which are thought to recognise both apoA-I and apoA-II.

  14. Apolipoprotein AI tertiary structures determine stability and phospholipid-binding activity of discoidal high-density lipoprotein particles of different sizes

    SciTech Connect

    Chen, Bin; Ren, Xuefeng; Neville, Tracey; Jerome, W. Gray; Hoyt, David W.; Sparks, Daniel L.; Ren, Gang; Wang, Jianjun

    2009-05-18

    Human high-density lipoprotein (HDL) plays a key role in the reverse cholesterol transport pathway that delivers excess cholesterol back to the liver for clearance. In vivo, HDL particles vary in size, shape and biological function. The discoidal HDL is a 140-240 kDa, disk-shaped intermediate of mature HDL. During mature spherical HDL formation, discoidal HDLs play a key role in loading cholesterol ester onto the HDL particles by activating the enzyme, lecithin:cholesterol acyltransferase (LCAT). One of the major problems for high-resolution structural studies of discoidal HDL is the difficulty in obtaining pure and, foremost, homogenous sample. We demonstrate here that the commonly used cholate dialysis method for discoidal HDL preparation usually contains 5-10% lipid-poor apoAI that significantly interferes with the high-resolution structural analysis of discoidal HDL using biophysical methods. Using an ultracentrifugation method, we quickly removed lipid-poor apoAI. We also purified discoidal reconstituted HDL (rHDL) into two pure discoidal HDL species of different sizes that are amendable for high-resolution structural studies. A small rHDL has a diameter of 7.6 nm, and a large rHDL has a diameter of 9.8 nm. We show that these two different sizes of discoidal HDL particles display different stability and phospholipid-binding activity. Interestingly, these property/functional differences are independent from the apoAI -helical secondary structure, but are determined by the tertiary structural difference of apoAI on different discoidal rHDL particles, as evidenced by two-dimensional NMR and negative stain electron microscopy data. Our result further provides the first high-resolution NMR data, demonstrating a promise of structural determination of discoidal HDL at atomic resolution using a combination of NMR and other biophysical techniques.

  15. A novel truncated form of apolipoprotein A-I transported by dense LDL is increased in diabetic patients1[S

    PubMed Central

    Cubedo, Judit; Padró, Teresa; García-Arguinzonis, Maisa; Vilahur, Gemma; Miñambres, Inka; Pou, Jose María; Ybarra, Juan; Badimon, Lina

    2015-01-01

    Diabetic (DM) patients have exacerbated atherosclerosis and high CVD burden. Changes in lipid metabolism, lipoprotein structure, and dysfunctional HDL are characteristics of diabetes. Our aim was to investigate whether serum ApoA-I, the main protein in HDL, was biochemically modified in DM patients. By using proteomic technologies, we have identified a 26 kDa ApoA-I form in serum. MS analysis revealed this 26 kDa form as a novel truncated variant lacking amino acids 1-38, ApoA-IΔ(1-38). DM patients show a 2-fold increase in ApoA-IΔ(1-38) over nondiabetic individuals. ApoA-IΔ(1-38) is found in LDL, but not in VLDL or HDL, with an increase in LDL3 and LDL4 subfractions. To identify candidate mechanisms of ApoA-I truncation, we investigated potentially involved enzymes by in silico data mining, and tested the most probable molecule in an established animal model of diabetes. We have found increased hepatic cathepsin D activity as one of the potential proteases involved in ApoA-I truncation. Cathepsin D-cleaved ApoA-I exhibited increased LDL binding affinity and decreased antioxidant activity against LDL oxidation. In conclusion, we show for the first time: a) presence of a novel truncated ApoA-I form, ApoA-IΔ(1-38), in human serum; b) ApoA-IΔ(1-38) is transported by LDL; c) ApoA-IΔ(1-38) is increased in dense LDL fractions of DM patients; and d) cathepsin D-ApoA-I truncation may lead to ApoA-IΔ(1-38) binding to LDLs, increasing their susceptibility to oxidation and contributing to the high cardiovascular risk of DM patients. PMID:26168996

  16. PEGylated helper-dependent adenoviral vector expressing human Apo A-I for gene therapy in LDLR-deficient mice.

    PubMed

    Leggiero, E; Astone, D; Cerullo, V; Lombardo, B; Mazzaccara, C; Labruna, G; Sacchetti, L; Salvatore, F; Croyle, M; Pastore, L

    2013-12-01

    Helper-dependent adenoviral (HD-Ad) vectors have great potential for gene therapy applications; however, their administration induces acute toxicity that impairs safe clinical applications. We previously observed that PEGylation of HD-Ad vectors strongly reduces the acute response in murine and primate models. To evaluate whether PEGylated HD-Ad vectors combine reduced toxicity with the correction of pathological phenotypes, we administered an HD-Ad vector expressing the human apolipoprotein A-I (hApoA-I) to low-density lipoprotein (LDL)-receptor-deficient mice (a model for familial hypercholesterolemia) fed a high-cholesterol diet. Mice were treated with high doses of HD-Ad-expressing apo A-I or its PEGylated version. Twelve weeks later, LDL levels were lower and high-density lipoprotein (HDL) levels higher in mice treated with either of the vectors than in untreated mice. After terminal killing, the areas of atherosclerotic plaques were much smaller in the vector-treated mice than in the control animals. Moreover, the increase in pro-inflammatory cytokines was lower and consequently the toxicity profile better in mice treated with PEGylated vector than in mice treated with the unmodified vector. This finding indicates that the reduction in toxicity resulting from PEGylation of HD-Ad vectors does not impair the correction of pathological phenotypes. It also supports the clinical potential of these vectors for the correction of genetic diseases.

  17. Human Cathelicidin Compensates for the Role of Apolipoproteins in Hepatitis C Virus Infectious Particle Formation

    PubMed Central

    Puig-Basagoiti, Francesc; Fukuhara, Takasuke; Tamura, Tomokazu; Ono, Chikako; Uemura, Kentaro; Kawachi, Yukako; Yamamoto, Satomi; Mori, Hiroyuki; Kurihara, Takeshi; Okamoto, Toru; Aizaki, Hideki

    2016-01-01

    ABSTRACT Exchangeable apolipoproteins (ApoA, -C, and -E) have been shown to redundantly participate in the formation of infectious hepatitis C virus (HCV) particles during the assembly process, although their precise role in the viral life cycle is not well understood. Recently, it was shown that the exogenous expression of only short sequences containing amphipathic α-helices from various apolipoproteins is sufficient to restore the formation of infectious HCV particles in ApoB and ApoE double-gene-knockout Huh7 (BE-KO) cells. In this study, through the expression of a small library of human secretory proteins containing amphipathic α-helix structures, we identified the human cathelicidin antimicrobial peptide (CAMP), the only known member of the cathelicidin family of antimicrobial peptides (AMPs) in humans and expressed mainly in bone marrow and leukocytes. We showed that CAMP is able to rescue HCV infectious particle formation in BE-KO cells. In addition, we revealed that the LL-37 domain in CAMP containing amphipathic α-helices is crucial for the compensation of infectivity in BE-KO cells, and the expression of CAMP in nonhepatic 293T cells expressing claudin 1 and microRNA miR-122 confers complete propagation of HCV. These results suggest the possibility of extrahepatic propagation of HCV in cells with low-level or no expression of apolipoproteins but expressing secretory proteins containing amphipathic α-helices such as CAMP. IMPORTANCE Various exchangeable apolipoproteins play a pivotal role in the formation of infectious HCV during the assembly of viral particles, and amphipathic α-helix motifs in the apolipoproteins have been shown to be a key factor. To the best of our knowledge, we have identified for the first time the human cathelicidin CAMP as a cellular protein that can compensate for the role of apolipoproteins in the life cycle of HCV. We have also identified the domain in CAMP that contains amphipathic α-helices crucial for compensation and

  18. Influence of domain stability on the properties of human apolipoprotein E3 and E4 and mouse apolipoprotein E.

    PubMed

    Nguyen, David; Dhanasekaran, Padmaja; Nickel, Margaret; Mizuguchi, Chiharu; Watanabe, Mayu; Saito, Hiroyuki; Phillips, Michael C; Lund-Katz, Sissel

    2014-06-24

    The human apolipoprotein (apo) E4 isoform, which differs from wild-type apoE3 by the single amino acid substitution C112R, is associated with elevated risk of cardiovascular and Alzheimer’s diseases, but the molecular basis for this variation between isoforms is not understood. Human apoE is a two-domain protein comprising an N-terminal helix bundle and a separately folded C-terminal region. Here, we examine the concept that the ability of the protein to bind to lipid surfaces is influenced by the stability (or readiness to unfold) of these domains. The lipid-free structures and abilities to bind to lipid and lipoprotein particles of a series of human and mouse apoE variants with varying domain stabilities and domain–domain interactions are compared. As assessed by urea denaturation, the two domains are more unstable in apoE4 than in apoE3. To distinguish the contributions of the destabilization of each domain to the greater lipid-binding ability of apoE4, the properties of the apoE4 R61T and E255A variants, which have the same helix bundle stabilities but altered C-terminal domain stabilities, are compared. In these cases, the effects on lipid-binding properties are relatively minor, indicating that the destabilization of the helix bundle domain is primarily responsible for the enhanced lipid-binding ability of apoE4. Unlike human apoE, mouse apoE behaves essentially as a single domain, and its lipid-binding characteristics are more similar to those of apoE4. Together, the results show that the overall stability of the entire apoE molecule exerts a major influence on its lipid- and lipoprotein-binding properties.

  19. Activation of lecithin cholesterol acyltransferase by human apolipoprotein E in discoidal complexes with lipids.

    PubMed

    Zorich, N; Jonas, A; Pownall, H J

    1985-07-25

    In a continued investigation of lecithin cholesterol acyltransferase reaction with micellar discoidal complexes of phosphatidylcholine, cholesterol, and various water soluble apolipoproteins, we prepared complexes containing human apo-E by the cholate dialysis method. These complexes were systematically compared to apo-A-I complexes synthesized under the same reaction conditions. Apo-E complexes (134 A in diameter) were slightly larger than apo-A-I complexes (110 A) but were very similar in terms of their protein and lipid content (2.4:0.10:1.0, egg phosphatidylcholine/cholesterol/apolipoprotein, w/w) and in the percentage of apolipoprotein in alpha-helical structure (72-74%). Concentration and temperature-dependence experiments on the velocity of the lecithin cholesterol acyltransferase reaction revealed differences in apparent Km values and small differences in apparent Vmax but very similar activation energies (18-20 kcal/mol). These observations suggest that differences in lecithin cholesterol acyltransferase activation by apo-A-I and apo-E are primarily a result of different affinities of the enzyme for the particles but that the rate-limiting step of the reaction is comparable for both complexes. Apo-E was found to be 18% as effective as apo-A-I in activating purified human lecithin cholesterol acyltransferase. Addition of free apo-A-I to apo-E complexes resulted in the exchange of bound for free apolipoprotein causing a slight increase in the reactivity with the enzyme when the incubation mixture was assayed. When the unbound apolipoproteins were removed by ultracentrifugation reisolated complexes containing both apo-E and apo-A-I demonstrated an even greater increase in reactivity with the enzyme.

  20. Lipoprotein lipase, LDL receptors and apo-lipoproteins in human fetal membranes at term.

    PubMed

    Huter, O; Wolf, H J; Schnetzer, A; Pfaller, K

    1997-11-01

    Ultrastructurally, all cells of human fetal membranes strongly exhibit a large amount of lipid deposits throughout pregnancy. Their origin and function is still unknown. The aim of this study was to investigate the localization of key components of lipid metabolism in this tissue. Using immunohistochemical techniques, the distribution of lipoprotein lipase (LPL), low density lipoprotein receptors (LDL receptors), and apo-lipoprotein B and E was investigated in 20 human fetal membranes at term. In addition, electron microscopy was used to study the intracellular localization of lipoprotein-sized particles. Amnionic epithelium and trophoblast cells reacted strongly for LPL. LDL receptors and apo-lipoproteins were present in amnionic epithelium and fibroblasts of the amnion. In none of the investigated cells were lipoprotein-sized particles identified. Similar results were obtained in all 20 cases. The findings indicate that lipoprotein from the amniotic fluid or from the maternal circulation may serve as substrate for lipids in human fetal membranes.

  1. Gene-centric Association Signals for Lipids and Apolipoproteins Identified via the HumanCVD BeadChip

    PubMed Central

    Talmud, Philippa J.; Drenos, Fotios; Shah, Sonia; Shah, Tina; Palmen, Jutta; Verzilli, Claudio; Gaunt, Tom R.; Pallas, Jacky; Lovering, Ruth; Li, Kawah; Casas, Juan Pablo; Sofat, Reecha; Kumari, Meena; Rodriguez, Santiago; Johnson, Toby; Newhouse, Stephen J.; Dominiczak, Anna; Samani, Nilesh J.; Caulfield, Mark; Sever, Peter; Stanton, Alice; Shields, Denis C.; Padmanabhan, Sandosh; Melander, Olle; Hastie, Claire; Delles, Christian; Ebrahim, Shah; Marmot, Michael G.; Smith, George Davey; Lawlor, Debbie A.; Munroe, Patricia B.; Day, Ian N.; Kivimaki, Mika; Whittaker, John; Humphries, Steve E.; Hingorani, Aroon D.

    2009-01-01

    Blood lipids are important cardiovascular disease (CVD) risk factors with both genetic and environmental determinants. The Whitehall II study (n = 5592) was genotyped with the gene-centric HumanCVD BeadChip (Illumina). We identified 195 SNPs in 16 genes/regions associated with 3 major lipid fractions and 2 apolipoprotein components at p < 10−5, with the associations being broadly concordant with prior genome-wide analysis. SNPs associated with LDL cholesterol and apolipoprotein B were located in LDLR, PCSK9, APOB, CELSR2, HMGCR, CETP, the TOMM40-APOE-C1-C2-C4 cluster, and the APOA5-A4-C3-A1 cluster; SNPs associated with HDL cholesterol and apolipoprotein AI were in CETP, LPL, LIPC, APOA5-A4-C3-A1, and ABCA1; and SNPs associated with triglycerides in GCKR, BAZ1B, MLXIPL, LPL, and APOA5-A4-C3-A1. For 48 SNPs in previously unreported loci that were significant at p < 10−4 in Whitehall II, in silico analysis including the British Women's Heart and Health Study, BRIGHT, ASCOT, and NORDIL studies (total n > 12,500) revealed previously unreported associations of SH2B3 (p < 2.2 × 10−6), BMPR2 (p < 2.3 × 10−7), BCL3/PVRL2 (flanking APOE; p < 4.4 × 10−8), and SMARCA4 (flanking LDLR; p < 2.5 × 10−7) with LDL cholesterol. Common alleles in these genes explained 6.1%–14.7% of the variance in the five lipid-related traits, and individuals at opposite tails of the additive allele score exhibited substantial differences in trait levels (e.g., >1 mmol/L in LDL cholesterol [∼1 SD of the trait distribution]). These data suggest that multiple common alleles of small effect can make important contributions to individual differences in blood lipids potentially relevant to the assessment of CVD risk. These genes provide further insights into lipid metabolism and the likely effects of modifying the encoded targets therapeutically. PMID:19913121

  2. Human liver apolipoprotein B-100 cDNA: complete nucleic acid and derived amino acid sequence.

    PubMed Central

    Law, S W; Grant, S M; Higuchi, K; Hospattankar, A; Lackner, K; Lee, N; Brewer, H B

    1986-01-01

    Human apolipoprotein B-100 (apoB-100), the ligand on low density lipoproteins that interacts with the low density lipoprotein receptor and initiates receptor-mediated endocytosis and low density lipoprotein catabolism, has been cloned, and the complete nucleic acid and derived amino acid sequences have been determined. ApoB-100 cDNAs were isolated from normal human liver cDNA libraries utilizing immunoscreening as well as filter hybridization with radiolabeled apoB-100 oligodeoxynucleotides. The apoB-100 mRNA is 14.1 kilobases long encoding a mature apoB-100 protein of 4536 amino acids with a calculated amino acid molecular weight of 512,723. ApoB-100 contains 20 potential glycosylation sites, and 12 of a total of 25 cysteine residues are located in the amino-terminal region of the apolipoprotein providing a potential globular structure of the amino terminus of the protein. ApoB-100 contains relatively few regions of amphipathic helices, but compared to other human apolipoproteins it is enriched in beta-structure. The delineation of the entire human apoB-100 sequence will now permit a detailed analysis of the conformation of the protein, the low density lipoprotein receptor binding domain(s), and the structural relationship between apoB-100 and apoB-48 and will provide the basis for the study of genetic defects in apoB-100 in patients with dyslipoproteinemias. PMID:3464946

  3. Several Human Liver Cell Expressed Apolipoproteins Complement HCV Virus Production with Varying Efficacy Conferring Differential Specific Infectivity to Released Viruses

    PubMed Central

    Doepke, Mandy; Vieyres, Gabrielle; Todt, Daniel; Wölk, Benno; Vondran, Florian W. R.; Geffers, Robert; Lauber, Chris; Kaderali, Lars; Penin, François; Pietschmann, Thomas

    2015-01-01

    Apolipoprotein E (ApoE), an exchangeable apolipoprotein, is necessary for production of infectious Hepatitis C virus (HCV) particles. However, ApoE is not the only liver-expressed apolipoprotein and the role of other apolipoproteins for production of infectious HCV progeny is incompletely defined. Therefore, we quantified mRNA expression of human apolipoproteins in primary human hepatocytes. Subsequently, cDNAs encoding apolipoproteins were expressed in 293T/miR-122 cells to explore if they complement HCV virus production in cells that are non-permissive due to limiting endogenous levels of human apolipoproteins. Primary human hepatocytes expressed high mRNA levels of ApoA1, A2, C1, C3, E, and H. ApoA4, A5, B, D, F, J, L1, L2, L3, L4, L6, M, and O were expressed at intermediate levels, and C2, C4, and L5 were not detected. All members of the ApoA and ApoC family of lipoproteins complemented HCV virus production in HCV transfected 293T/miR-122 cells, albeit with significantly lower efficacy compared with ApoE. In contrast, ApoD expression did not support production of infectious HCV. Specific infectivity of released particles complemented with ApoA family members was significantly lower compared with ApoE. Moreover, the ratio of extracellular to intracellular infectious virus was significantly higher for ApoE compared to ApoA2 and ApoC3. Since apolipoproteins complementing HCV virus production share amphipathic alpha helices as common structural features we altered the two alpha helices of ApoC1. Helix breaking mutations in both ApoC1 helices impaired virus assembly highlighting a critical role of alpha helices in apolipoproteins supporting HCV assembly. In summary, various liver expressed apolipoproteins with amphipathic alpha helices complement HCV virus production in human non liver cells. Differences in the efficiency of virus assembly, the specific infectivity of released particles, and the ratio between extracellular and intracellular infectivity point to

  4. Lipoprotein remodeling generates lipid-poor apolipoprotein A-I particles in human interstitial fluid

    PubMed Central

    Olszewski, Waldemar L.; Hattori, Hiroaki; Miller, Irina P.; Kujiraoka, Takeshi; Oka, Tomoichiro; Iwasaki, Tadao; Nanjee, M. Nazeem

    2013-01-01

    Although much is known about the remodeling of high density lipoproteins (HDLs) in blood, there is no information on that in interstitial fluid, where it might have a major impact on the transport of cholesterol from cells. We incubated plasma and afferent (prenodal) peripheral lymph from 10 healthy men at 37°C in vitro and followed the changes in HDL subclasses by nondenaturing two-dimensional crossed immunoelectrophoresis and size-exclusion chromatography. In plasma, there was always initially a net conversion of small pre-β-HDLs to cholesteryl ester (CE)-rich α-HDLs. By contrast, in lymph, there was only net production of pre-β-HDLs from α-HDLs. Endogenous cholesterol esterification rate, cholesteryl ester transfer protein (CETP) concentration, CE transfer activity, phospholipid transfer protein (PLTP) concentration, and phospholipid transfer activity in lymph averaged 5.0, 10.4, 8.2, 25.0, and 82.0% of those in plasma, respectively (all P < 0.02). Lymph PLTP concentration, but not phospholipid transfer activity, was positively correlated with that in plasma (r = +0.63, P = 0.05). Mean PLTP-specific activity was 3.5-fold greater in lymph, reflecting a greater proportion of the high-activity form of PLTP. These findings suggest that cholesterol esterification rate and PLTP specific activity are differentially regulated in the two matrices in accordance with the requirements of reverse cholesterol transport, generating lipid-poor pre-β-HDLs in the extracellular matrix for cholesterol uptake from neighboring cells and converting pre-β-HDLs to α-HDLs in plasma for the delivery of cell-derived CEs to the liver. PMID:23233540

  5. Expression of human apolipoprotein B and assembly of lipoprotein(a) in transgenic mice

    SciTech Connect

    Callow, M.J.; Stoltzfus, L.J.; Rubin, E.M.; Lawn, R.M.

    1994-03-15

    The atherogenic macromolecule lipoprotein(a) [Lp(a)] has resisted in vivo analyses partly because it is found in a limited number of experimental animals. Although transgenic mice expressing human apolipoprotein (a) [apo(a)] have previously been described, they failed to assemble Lp(a) particles because of the inability of human apo(a) to associate with mouse apolipoprotein B (apoB). The authors isolated a 90-kilobase P1 phagemid containing the human apoB gene and with this DNA generated 13 lines of transgenic mice of which 11 expressed human apoB. The human apoB transcript was expressed and edited in the liver of the transgenic mice. Plasma concentrations of human apoB, as well as low density lipoprotein (LDL), were related to transgene copy number; the transgenic line with the most copies of human apoB had a >4-fold increase in LDL cholesterol compared with nontransgenics and a lipoprotein profile similar to that of humans. When human apoB and apo(a) transgenic mice were bred together, plasma apo(a) in mice expressing both human proteins was tightly associated with lipoproteins in the LDL density region. These studies demonstrate the successful expression of human apoB and the efficient assembly of Lp(a) in mice.

  6. Characterization of monoclonal antibodies against human apolipoprotein E.

    PubMed Central

    Milne, R W; Douste-Blazy, P; Marcel, Y L; Retegui, L

    1981-01-01

    From a single cell fusion, five stable hybridomas secreting antiapolipoprotein E (apo E) were obtained. The immunoglobulin (Ig)G subclasses containing the respective monoclonal antibodies were isolated and were used as the antibody component in a solid-phase radioimmunoassay. The binding of 125I-apo E to the insolubilized antibody was inhibited by unlabeled apo E but not by unlabeled apoproteins A-I, A-II, C-II, and C-III, or by low density lipoprotein immunodepleted of endogenous apo E. Competition curves were obtained with lipoprotein subfractions that had the same shape as those obtained with purified apo E. Apo E levels in normal and hyperlipidemic plasma were well correlated when measured by the five monoclonal antibodies and polyclonal anti-apo E, although differences in absolute values were observed. In normal subjects 34, 10, 20, and 36% of apo E was recovered in the very low density lipoprotein, low density lipoprotein, high density lipoprotein, and the d greater than 1.21-gl/ml fractions, respectively, whereas these values were 34, 7, 12, and 47%, respectively, in type III patients. All antibodies indicated the same subfraction distribution of apo E. The monoclonal antibodies reacted with all of the isomorphs of apo E. One of the antibodies could be clearly distinguished by its reactivity with chemically modified very low density lipoprotein. Images PMID:6788802

  7. Serum amyloid A-containing human high density lipoprotein 3. Density, size, and apolipoprotein composition.

    PubMed

    Coetzee, G A; Strachan, A F; van der Westhuyzen, D R; Hoppe, H C; Jeenah, M S; de Beer, F C

    1986-07-25

    Serum amyloid A protein (apo-SAA), an acute phase reactant, is an apolipoprotein of high density lipoproteins (HDL), in particular the denser subpopulation HDL3. The structure of HDL3 isolated from humans affected by a variety of severe disease states was investigated with respect to density, size, and apolipoprotein composition, using density gradient ultracentrifugation, gradient gel electrophoresis, gel filtration, and solid phase immunoadsorption. Apo-SAA was present in HDL particles in increasing amounts as particle density increased. Apo-SAA-containing HDL3 had bigger radii than normal HDL3 of comparable density. Purified apo-SAA associated readily with normal HDL3 in vitro, giving rise to particles containing up to 80% of their apoproteins as apo-SAA. The addition of apo-SAA resulted in a displacement of apo-A-I and an increase in particle size. Acute phase HDL3 represented a mixture of particles, polydisperse with respect to apolipoprotein content; for example, some particles were isolated that contained apo-A-I, apo-A-II, and apo-SAA, whereas others contained apo-A-I and apo-SAA but no apo-A-II. We conclude that apo-SAA probably associates in the circulation of acute phase patients with existing HDL particles, causing the remodeling of the HDL shell to yield particles of bigger size and higher density that are relatively depleted of apo-A-I.

  8. Characterization of disulfide-linked heterodimers containing apolipoprotein D in human plasma lipoproteins.

    PubMed

    Blanco-Vaca, F; Via, D P; Yang, C Y; Massey, J B; Pownall, H J

    1992-12-01

    Human plasma apolipoprotein (apo) D is a glycoprotein with an apparent molecular weight of 29,000 M(r). It is present, mainly, in high density lipoproteins (HDL) and very high density lipoproteins (VHDL). Western blot analysis of HDL and VHDL using rabbit antibodies to human apoD revealed major immunoreactive bands at 29,000 and 38,000 M(r), with minor bands ranging from 50,000 to and 80,000 M(r). Only the 29,000 M(r) band corresponding to apoD remained when the electrophoresis was conducted under reducing conditions, demonstrating that apoD is cross-linked to other proteins via disulfide bonds. The broad pattern of immunoreactivity was also observed under nonreducing conditions when the blood was collected into a solution of sulfhydryl-trapping reagents, or when these reagents were added to the isolated lipoproteins. These results indicated that the disulfide bonds were not the result of disulfide exchange during the experimental procedures. On the basis of amino acid sequencing and reactions to antibodies, the 38,000 M(r) band was identified as an apoD-apoA-II heterodimer. The apoD-apoA-II was also demonstrated in plasma. In both HDL and plasma, the apoD-apoA-II heterodimer constituted the major form of apoD. Disulfide-linked heterodimers of apoD and apoB-100 were also found in low and very low density lipoproteins, and in whole plasma. It is concluded that a fraction of human apoD, like other cysteine-containing apolipoproteins, exists as a disulfide-linked heterodimer with other apolipoproteins in all major human lipoprotein fractions.

  9. Human leucine zipper protein promotes hepatic steatosis via induction of apolipoprotein A-IV.

    PubMed

    Kang, Minsoo; Kim, Jeonghan; An, Hyoung-Tae; Ko, Jesang

    2017-02-28

    The molecular mechanism of stress-induced hepatic steatosis is not well known. Human leucine zipper protein (LZIP) regulates the expression of genes involved in inflammation, cell migration, and stress response. The aim of this study was to determine the regulatory role of LZIP in stress-induced hepatic steatosis. We used a microarray analysis to identify LZIP-induced genes involved in hepatic lipid metabolism. LZIP increased the expression of apolipoprotein A-IV (APOA4) mRNA. In the presence of stress inducer, APOA4 promoter analysis was performed and LZIP-induced lipid accumulation was monitored in mouse primary cells and human tissues. Under Golgi stress conditions, LZIP underwent proteolytic cleavage and was phosphorylated by AKT to protect against proteasome degradation. The stabilized N-terminal LZIP was translocated to the nucleus, where it directly bound to the APOA4 promoter, leading to APOA4 induction. LZIP-induced APOA4 expression resulted in increased absorption of surrounding free fatty acids. LZIP also promoted hepatic steatosis in mouse liver. Both LZIP and APOA4 were highly expressed in human steatosis samples. Our findings indicate that LZIP is a novel modulator of APOA4 expression and hepatic lipid metabolism. LZIP might be a therapeutic target for developing treatment strategies for hepatic steatosis and related metabolic diseases.-Kang, M., Kim, J., An, H.-T., Ko, J. Human leucine zipper protein promotes hepatic steatosis via induction of apolipoprotein A-IV.

  10. Analysis of cell surface alterations in Legionella pneumophila cells treated with human apolipoprotein E.

    PubMed

    Palusinska-Szysz, Marta; Zdybicka-Barabas, Agnieszka; Cytryńska, Małgorzata; Wdowiak-Wróbel, Sylwia; Chmiel, Elżbieta; Gruszecki, Wiesław I

    2015-03-01

    Binding of human apolipoprotein E (apoE) to Legionella pneumophila lipopolysaccharide was analysed at the molecular level by Fourier-transform infrared spectroscopy, thereby providing biophysical evidence for apoE-L. pneumophila lipopolysaccharide interaction. Atomic force microscopy imaging of apoE-exposed L. pneumophila cells revealed alterations in the bacterial cell surface topography and nanomechanical properties in comparison with control bacteria. The changes induced by apoE binding to lipopolysaccharide on the surface of L. pneumophila cells may participate in: (1) impeding the penetration of host cells by the bacteria; (2) suppression of pathogen intracellular growth and eventually; and (3) inhibition of the development of infection.

  11. Human Apolipoprotein A-I-Derived Amyloid: Its Association with Atherosclerosis

    PubMed Central

    Ramella, Nahuel A.; Rimoldi, Omar J.; Prieto, Eduardo D.; Schinella, Guillermo R.; Sanchez, Susana A.; Jaureguiberry, María S.; Vela, María E.

    2011-01-01

    Amyloidoses constitute a group of diseases in which soluble proteins aggregate and deposit extracellularly in tissues. Nonhereditary apolipoprotein A-I (apoA-I) amyloid is characterized by deposits of nonvariant protein in atherosclerotic arteries. Despite being common, little is known about the pathogenesis and significance of apoA-I deposition. In this work we investigated by fluorescence and biochemical approaches the impact of a cellular microenvironment associated with chronic inflammation on the folding and pro-amyloidogenic processing of apoA-I. Results showed that mildly acidic pH promotes misfolding, aggregation, and increased binding of apoA-I to extracellular matrix elements, thus favoring protein deposition as amyloid like-complexes. In addition, activated neutrophils and oxidative/proteolytic cleavage of the protein give rise to pro amyloidogenic products. We conclude that, even though apoA-I is not inherently amyloidogenic, it may produce non hereditary amyloidosis as a consequence of the pro-inflammatory microenvironment associated to atherogenesis. PMID:21811627

  12. Glomerular Autoimmune Multicomponents of Human Lupus Nephritis In Vivo: α-Enolase and Annexin AI

    PubMed Central

    Bruschi, Maurizio; Sinico, Renato Alberto; Moroni, Gabriella; Pratesi, Federico; Migliorini, Paola; Galetti, Maricla; Murtas, Corrado; Tincani, Angela; Madaio, Michael; Radice, Antonella; Franceschini, Franco; Trezzi, Barbara; Bianchi, Laura; Giallongo, Agata; Gatti, Rita; Tardanico, Regina; Scaloni, Andrea; D’Ambrosio, Chiara; Carnevali, Maria Luisa; Messa, Piergiorgio; Ravani, Pietro; Barbano, Giancarlo; Bianco, Beatrice; Bonanni, Alice; Scolari, Francesco; Martini, Alberto; Candiano, Giovanni; Allegri, Landino

    2014-01-01

    Renal targets of autoimmunity in human lupus nephritis (LN) are unknown. We sought to identify autoantibodies and glomerular target antigens in renal biopsy samples from patients with LN and determine whether the same autoantibodies can be detected in circulation. Glomeruli were microdissected from biopsy samples of 20 patients with LN and characterized by proteomic techniques. Serum samples from large cohorts of patients with systemic lupus erythematosus (SLE) with and without LN and other glomerulonephritides were tested. Glomerular IgGs recognized 11 podocyte antigens, with reactivity varying by LN pathology. Notably, IgG2 autoantibodies against α-enolase and annexin AI were detected in 11 and 10 of the biopsy samples, respectively, and predominated over other autoantibodies. Immunohistochemistry revealed colocalization of α-enolase or annexin AI with IgG2 in glomeruli. High levels of serum anti–α-enolase (>15 mg/L) IgG2 and/or anti-annexin AI (>2.7 mg/L) IgG2 were detected in most patients with LN but not patients with other glomerulonephritides, and they identified two cohorts: patients with high anti–α-enolase/low anti-annexin AI IgG2 and patients with low anti–α-enolase/high anti-annexin AI IgG2. Serum levels of both autoantibodies decreased significantly after 12 months of therapy for LN. Anti–α-enolase IgG2 recognized specific epitopes of α-enolase and did not cross-react with dsDNA. Furthermore, nephritogenic monoclonal IgG2 (clone H147) derived from lupus-prone MRL-lpr/lpr mice recognized human α-enolase, suggesting homology between animal models and human LN. These data show a multiantibody composition in LN, where IgG2 autoantibodies against α-enolase and annexin AI predominate in the glomerulus and can be detected in serum. PMID:24790181

  13. Glomerular autoimmune multicomponents of human lupus nephritis in vivo: α-enolase and annexin AI.

    PubMed

    Bruschi, Maurizio; Sinico, Renato Alberto; Moroni, Gabriella; Pratesi, Federico; Migliorini, Paola; Galetti, Maricla; Murtas, Corrado; Tincani, Angela; Madaio, Michael; Radice, Antonella; Franceschini, Franco; Trezzi, Barbara; Bianchi, Laura; Giallongo, Agata; Gatti, Rita; Tardanico, Regina; Scaloni, Andrea; D'Ambrosio, Chiara; Carnevali, Maria Luisa; Messa, Piergiorgio; Ravani, Pietro; Barbano, Giancarlo; Bianco, Beatrice; Bonanni, Alice; Scolari, Francesco; Martini, Alberto; Candiano, Giovanni; Allegri, Landino; Ghiggeri, Gian Marco

    2014-11-01

    Renal targets of autoimmunity in human lupus nephritis (LN) are unknown. We sought to identify autoantibodies and glomerular target antigens in renal biopsy samples from patients with LN and determine whether the same autoantibodies can be detected in circulation. Glomeruli were microdissected from biopsy samples of 20 patients with LN and characterized by proteomic techniques. Serum samples from large cohorts of patients with systemic lupus erythematosus (SLE) with and without LN and other glomerulonephritides were tested. Glomerular IgGs recognized 11 podocyte antigens, with reactivity varying by LN pathology. Notably, IgG2 autoantibodies against α-enolase and annexin AI were detected in 11 and 10 of the biopsy samples, respectively, and predominated over other autoantibodies. Immunohistochemistry revealed colocalization of α-enolase or annexin AI with IgG2 in glomeruli. High levels of serum anti-α-enolase (>15 mg/L) IgG2 and/or anti-annexin AI (>2.7 mg/L) IgG2 were detected in most patients with LN but not patients with other glomerulonephritides, and they identified two cohorts: patients with high anti-α-enolase/low anti-annexin AI IgG2 and patients with low anti-α-enolase/high anti-annexin AI IgG2. Serum levels of both autoantibodies decreased significantly after 12 months of therapy for LN. Anti-α-enolase IgG2 recognized specific epitopes of α-enolase and did not cross-react with dsDNA. Furthermore, nephritogenic monoclonal IgG2 (clone H147) derived from lupus-prone MRL-lpr/lpr mice recognized human α-enolase, suggesting homology between animal models and human LN. These data show a multiantibody composition in LN, where IgG2 autoantibodies against α-enolase and annexin AI predominate in the glomerulus and can be detected in serum.

  14. Transgenic mice expressing high plasma concentrations of human apolipoprotein B100 and lipoprotein(a).

    PubMed Central

    Linton, M F; Farese, R V; Chiesa, G; Grass, D S; Chin, P; Hammer, R E; Hobbs, H H; Young, S G

    1993-01-01

    The B apolipoproteins, apo-B48 and apo-B100, are key structural proteins in those classes of lipoproteins considered to be atherogenic [e.g., chylomicron remnants, beta-VLDL, LDL, oxidized LDL, and Lp(a)]. Here we describe the development of transgenic mice expressing high levels of human apo-B48 and apo-B100. A 79.5-kb human genomic DNA fragment containing the entire human apo-B gene was isolated from a P1 bacteriophage library and microinjected into fertilized mouse eggs. 16 transgenic founders expressing human apo-B were generated, and the animals with the highest expression had plasma apo-B100 levels nearly as high as those of normolipidemic humans (approximately 50 mg/dl). The human apo-B100 in transgenic mouse plasma was present largely in lipoproteins of the LDL class as shown by agarose gel electrophoresis, chromatography on a Superose 6 column, and density gradient ultracentrifugation. When the human apo-B transgenic founders were crossed with transgenic mice expressing human apo(a), the offspring that expressed both transgenes had high plasma levels of human Lp(a). Both the human apo-B and Lp(a) transgenic mice will be valuable resources for studying apo-B metabolism and the role of apo-B and Lp(a) in atherosclerosis. Images PMID:8254057

  15. Unusually high reactivity of apolipoprotein B-100 among proteins to radical reactions induced in human plasma.

    PubMed

    Hashimoto, R; Narita, S; Yamada, Y; Tanaka, K; Kojo, S

    2000-01-17

    Relative reactivities of proteins to radical reactions caused in human plasma were studied for the first time utilizing an immunoblotting assay. When radical reactions were caused by Cu(2+), apolipoprotein B-100 (apoB) underwent extensive fragmentation concurrently with the decrease in alpha-tocopherol, while human serum albumin (HSA) and transferrin (TF) were not decreased at all. When radical reactions were initiated by Cu(2+) with hydrogen peroxide or 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), alpha-tocopherol and apoB were also decreased steadily but HSA and TF were not decreased. These observations indicate that apoB is extremely reactive, even comparable to alpha-tocopherol, towards radical reactions. These results also suggest that the radical reaction of apoB is a possible process in vivo and it is involved in atherogenesis along with low density lipoprotein lipid peroxidation, which has been studied extensively.

  16. High-density lipoprotein and apolipoprotein A-I inhibit palmitate-induced translocation of toll-like receptor 4 into lipid rafts and inflammatory cytokines in 3T3-L1 adipocytes.

    PubMed

    Yamada, Hodaka; Umemoto, Tomio; Kawano, Mikihiko; Kawakami, Masanobu; Kakei, Masafumi; Momomura, Shin-Ichi; Ishikawa, San-E; Hara, Kazuo

    2017-03-04

    Saturated fatty acids (SFAs) activate toll-like receptor 4 (TLR4) signal transduction in macrophages and are involved in the chronic inflammation accompanying obesity. High-density lipoprotein (HDL) and apolipoprotein A-I (apoA-I) produce anti-inflammatory effects via reverse cholesterol transport. However, the underlying mechanisms by which HDL and apoA-I inhibit inflammatory responses in adipocytes remain to be determined. Here we examined whether palmitate increases the translocation of TLR4 into lipid rafts and whether HDL and apoA-I inhibit inflammation in adipocytes. Palmitate exposure (250 μM, 24 h) increased interleukin-6 and tumor necrosis factor-α gene expressions and translocation of TLR4 into lipid rafts in 3T3-L1 adipocytes. Pretreatment with HDL and apoA-I (50 μg/mL, 6 h) suppressed palmitate-induced inflammatory cytokine expression and TLR4 translocation into lipid rafts. Moreover, HDL and apoA-I inhibited palmitate-induced phosphorylation of nuclear factor-kappa B. HDL showed an anti-inflammatory effect via ATP-binding cassette transporter G1 and scavenger receptor class B, member 1, whereas apoA-I showed an effect via ATP-binding cassette transporter A1. These results demonstrated that HDL and apoA-I reduced palmitate-potentiated TLR4 trafficking into lipid rafts and its related inflammation in adipocytes via these specific transporters.

  17. Patterns of association between genetic variability in apolipoprotein (apo) B, apo AI-CIII-AIV, and cholesterol ester transfer protein gene regions and quantitative variation in lipid and lipoprotein traits: influence of gender and exogenous hormones.

    PubMed Central

    Kessling, A; Ouellette, S; Bouffard, O; Chamberland, A; Bétard, C; Selinger, E; Xhignesse, M; Lussier-Cacan, S; Davignon, J

    1992-01-01

    Patterns of RFLP association were studied, to identify gene regions influencing quantitative variation in lipid and lipoprotein traits (coronary artery disease [CAD] risk factors or metabolically related traits). Subjects (118 female and 229 male; age 20-59 years) were selected for health. Multiple RFLPs were used to sample variability in regions around genes for apolipoprotein (apo) B (restriction enzymes HincII, PvuII, EcoRI, and XbaI), apo AI-CIII-AIV (BamHI, XmnI, TaqI, PstI, SstI, and PvuII) and cholesterol ester transfer protein (TaqI). Separate analyses were done by gender. The sample was truncated at mean +/- 4 SD, to remove extreme outliers. There was no significant gender difference in RFLP genotype frequency distribution. After trait-level adjustment to maximize removal of concomitant variability, analysis of variance was used to estimate the percentage trait phenotypic variance explained by measured variability in the gene regions studied. Fewer gene regions were involved in men, with less influence on quantitative trait variation than in women, in whom hormone use affected association patterns. Gender differences imply that pooling genders or adjusting data for gender effects removes genetic information and should be avoided. The association patterns show that variability around the candidate genes modulates trait levels: the genes are contributors to the genetics of CAD risk variables in a healthy sample. PMID:1346081

  18. Orphan nuclear receptor Nur77 participates in human apolipoprotein A5 gene expression

    SciTech Connect

    Song, Kwang-Hoon

    2010-01-29

    The orphan nuclear receptor Nur77 (NR4A1) has been reported to play a crucial role in the modulation of diverse metabolic processes in liver. Here, we reported the identification of human apolipoprotein A5 (ApoA5), which implicated in lowering plasma triglyceride levels, as a novel target gene of Nur77. Nur77 induced the human ApoA5 promoter activity. Using 5'-deletion and mutagenesis of human ApoA5 promoter analysis and chromatin immunoprecipitation assays, it was shown that Nur77 directly regulated human ApoA5 gene expression by binding to a Nur77 response element (AAAGGTCA) located in the proximal human ApoA5 promoter region. In addition, we demonstrated that blocking of Nur77 transcriptional activity via overexpression of dominant negative Nur77 suppressed human ApoA5 promoter activity and mRNA expression in human hepatoma cells, HepG2. Taken together, our results demonstrated that Nur77 is a novel regulator of human ApoA5 gene expression and provide a new insight into the role of this orphan nuclear receptor in lipoprotein metabolism and triglyceride homeostasis.

  19. Human apolipoprotein B transgenic SHR/NDmcr-cp rats show exacerbated kidney dysfunction.

    PubMed

    Asahina, Makoto; Shimizu, Fumi; Ohta, Masayuki; Takeyama, Michiyasu; Tozawa, Ryuichi

    2015-01-01

    Nephropathy frequently co-occurs with metabolic syndrome in humans. Metabolic syndrome is a cluster of metabolic diseases including obesity, diabetes, hypertension, and dyslipidemia, and some previous studies revealed that dyslipidemia contributes to the progression of kidney dysfunction. To establish a new nephropathy model with metabolic syndrome, we produced human apolipoprotein B (apoB) transgenic (Tg.) SHR/NDmcr-cp (SHR-cp/cp) rats, in which dyslipidemia is exacerbated more than in an established metabolic syndrome model, SHR-cp/cp rats. Human apoB Tg. SHR-cp/cp rats showed obesity, hyperinsulinemia, hypertension, and severe hyperlipidemia. They also exhibited exacerbated early-onset proteinuria, accompanied by increased kidney injury and increased oxidative and inflammatory markers. Histological analyses revealed the characteristic features of human apoB Tg. SHR-cp/cp rats including prominent glomerulosclerosis with lipid accumulation. Our newly established human apoB Tg. SHR-cp/cp rat could be a useful model for the nephropathy in metabolic syndrome and for understanding the interaction between dyslipidemia and renal dysfunction in metabolic syndrome.

  20. Production of human apolipoprotein(a) transgenic NIBS miniature pigs by somatic cell nuclear transfer.

    PubMed

    Shimatsu, Yoshiki; Horii, Wataru; Nunoya, Tetsuo; Iwata, Akira; Fan, Jianglin; Ozawa, Masayuki

    2016-01-01

    Most cases of ischemic heart disease and stroke occur as a result of atherosclerosis. The purpose of this study was to produce a new Nippon Institute for Biological Science (NIBS) miniature pig model by somatic cell nuclear transfer (SCNT) for studying atherosclerosis. The human apolipoprotein(a) (apo(a)) genes were transfected into kidney epithelial cells derived from a male and a female piglet. Male cells were used as donors initially, and 275 embryos were transferred to surrogates. Three offspring were delivered, and the production efficiency was 1.1% (3/275). Serial female cells were injected into 937 enucleated oocytes. Eight offspring were delivered (production efficiency: 0.9%) from surrogates. One male and 2 female transgenic miniature pigs matured well. Lipoprotein(a) was found in the male and one of the female transgenic animals. These results demonstrate successful production of human apo(a) transgenic NIBS miniature pigs by SCNT. Our goal is to establish a human apo(a) transgenic NIBS miniature pig colony for studying atherosclerosis.

  1. Apolipoprotein A5: A newly identified gene impacting plasmatriglyceride levels in humans and mice

    SciTech Connect

    Pennacchio, Len A.; Rubin, Edward M.

    2002-09-15

    Apolipoprotein A5 (APOA5) is a newly described member of theapolipoprotein gene family whose initial discovery arose from comparativesequence analysis of the mammalian APOA1/C3/A4 gene cluster. Functionalstudies in mice indicated that alteration in the level of APOA5significantly impacted plasma triglyceride concentrations. Miceover-expressing human APOA5 displayed significantly reducedtriglycerides, while mice lacking apoA5 had a large increase in thislipid parameter. Studies in humans have also suggested an important rolefor APOA5 in determining plasma triglyceride concentrations. In theseexperiments, polymorphisms in the human gene were found to define severalcommon haplotypes that were associated with significant changes intriglyceride concentrations in multiple populations. Several separateclinical studies have provided consistent and strong support for theeffect with 24 percent of Caucasians, 35 percent of African-Americans and53 percent of Hispanics carrying APOA5 haplotypes associated withincreased plasma triglyceride levels. In summary, APOA5 represents anewly discovered gene involved in triglyceride metabolism in both humansand mice whose mechanism of action remains to be deciphered.

  2. Production of Cloned Miniature Pigs Expressing High Levels of Human Apolipoprotein(a) in Plasma

    PubMed Central

    Ozawa, Masayuki; Himaki, Takehiro; Ookutsu, Shoji; Mizobe, Yamato; Ogawa, Junki; Miyoshi, Kazuchika; Yabuki, Akira; Fan, Jianglin; Yoshida, Mitsutoshi

    2015-01-01

    High lipoprotein(a) [Lp(a)] levels are a major risk factor for the development of atherosclerosis. However, because apolipoprotein(a) [apo(a)], the unique component of Lp(a), is found only in primates and humans, the study of human Lp(a) has been hampered due to the lack of appropriate animal models. Using somatic cell nuclear transfer (SCNT) techniques, we produced transgenic miniature pigs expressing human apo(a) in the plasma. First, we placed the hemagglutinin (HA)-tagged cDNA of human apo(a) under the control of the β-actin promoter and cytomegalovirus enhancer, and then introduced this construct into kidney epithelial cells. Immunostaining of cells with anti-HA antibody allowed identification of cells stably expressing apo(a); one of the positive clones was used to provide donor cells for SCNT, yielding blastocysts that expressed apo(a). Immunohistochemical analysis of tissue sections and RT-PCR analysis of total RNA from organs of cloned piglet revealed that apo(a) is expressed in various tissues/organs including heart, liver, kidney, and intestine. More importantly, a transgenic line exhibited a high level (>400 mg/dL) of Lp(a) in plasma, and the transgenic apo(a) gene was transmitted to the offspring. Thus, we generated a human apo(a)–transgenic miniature pig that can be used as a model system to study advanced atherosclerosis related to human disease. The anatomical and physiological similarities between the swine and human cardiovascular systems will make this pig model a valuable source of information on the role of apo(a) in the formation of atherosclerosis, as well as the mechanisms underlying vascular health and disease. PMID:26147378

  3. Macrophage-specific expression of human apolipoprotein E reduces atherosclerosis in hypercholesterolemic apolipoprotein E-null mice.

    PubMed Central

    Bellosta, S; Mahley, R W; Sanan, D A; Murata, J; Newland, D L; Taylor, J M; Pitas, R E

    1995-01-01

    apoE deficiency causes hyperlipidemia and premature atherosclerosis. To determine if macrophage-specific expression of apoE would decrease the extent of atherosclerosis, we expressed human apoE in macrophages of apoE-null mice (apoE-/-) and assessed the effect on lipid accumulation in cells of the arterial wall. Macrophage-specific expression of human apoE in normal mice was obtained by use of the visna virus LTR. These animals were bred with apoE-/- mice to produce animals hemizygous for expression of human apoE in macrophages in the absence of murine apoE (apoE-/-,hTgE+/0). Low levels of human apoE mRNA were present in liver and spleen and high levels in lung and peritoneal macrophages. Human apoE was secreted by peritoneal macrophages and was detected in Kupffer cells of the liver. Human apoE in the plasma of apoE-/-,hTgE+/0 mice (n = 30) was inversely correlated (P < 0.005) with the plasma cholesterol concentration. After 15 wk on a normal chow diet, atherosclerosis was assessed in apoE-/-,hTgE+/0 animals and in apoE-/-,hTgE0/0 littermates matched for plasma cholesterol level (approximately 450 mg/dl) and lipoprotein profile. There was significantly less atherosclerosis in both the aortic sinus and in the proximal aorta (P < 0.0001) in the animals expressing the human apoE transgene. In apo-E-/-,hTgE+/0 animals, which had detectable atherosclerotic lesions, human apoE was detected in the secretory apparatus of macrophage-derived foam cells in the arterial wall. The data demonstrate that expression of apoE by macrophages is antiatherogenic even in the presence of high levels of atherogenic lipoproteins. The data suggest that apoE prevents atherosclerosis by promoting cholesterol efflux from cells of the arterial wall. Images PMID:7593602

  4. Comparative surface antimicrobial properties of synthetic biocides and novel human apolipoprotein E derived antimicrobial peptides.

    PubMed

    Forbes, Sarah; McBain, Andrew J; Felton-Smith, Susan; Jowitt, Thomas A; Birchenough, Holly L; Dobson, Curtis B

    2013-07-01

    Medical device infection remains a major clinical concern. Biocidal compounds have been incorporated into medical device materials ideally to inhibit bacterial colonisation whilst exhibiting relatively low cytotoxicity. We compared the antibacterial activity, anti-biofilm efficacy and cytotoxicity of a novel peptide derivative of human apolipoprotein E (apoEdpL-W) to that of commonly used biocides, before and after coating onto a range of standard polymers. Since the antimicrobial function of most biocides frequently involves associations with cellular membranes, we have also studied the detailed interactions of the test antimicrobials with phospholipid bilayers, using the quartz crystal microbalance device combined with dual-polarisation interferometry. ApoEdpL-W displayed broad-spectrum antibacterial activity and marked efficacy against nascent Staphylococcus aureus biofilms. Compounds showed better antimicrobial activity when combined with hydrogel materials than with non-porous materials. The membrane interactions of apoEdpL-W were most similar to that of PHMB, with both agents appearing to readily bind and insert into lipid bilayers, possibly forming pores. However apoEdpL-W showed lower cytotoxicity than PHMB, its efficacy was less affected by the presence of serum, and it demonstrated the highest level of biocompatibility of all the biocides, as indicated by our measurement of its antimicrobial biocompatibility index. This work shows the potential of apoEdpL-W as an effective antiseptic coating agent.

  5. Expression of the human apolipoprotein E gene suppresses steroidogenesis in mouse Y1 adrenal cells

    SciTech Connect

    Reyland, M.E.; Forgez, P.; Prack, M.M.; Williams, D.L. ); Gwynne, J.T. )

    1991-03-15

    The lipid transport protein, apolipoprotein E (apoE), is expressed in many peripheral tissues in vivo including the adrenal gland and testes. To investigate the role of apoE in adrenal cholesterol homeostasis, the authors have expressed a human apoE genomic clone in the Y1 mouse adrenocortical cell line. Y1 cells do not express endogenous apoE mRNA or protein. Expression of apoE in Y1 cells resulted in a dramatic decrease in basal steroidogenesis; secretion of fluorogenic steroid was reduced 7- to {gt}100-fold relative to Y1 parent cells. Addition of 5-cholesten-3{beta},25-idol failed to overcome the suppression of steroidogenesis in these cells. Cholesterol esterification under basal conditions, as measured by the production of cholesteryl ({sup 14}C)oleate, was similar in the Y1 parent and the apoE-transfected cell lines. Upon incubation with adrenocorticotropin or dibutyryl cAMP, production of cholesteryl ({sup 14}C)oleate decreased 5-fold in the Y1 parent cells but was unchanged in the apoE-transfected cell lines. These results suggest that apoE may be an important modulator of cholesterol utilization and steroidogenesis in adrenal cells.

  6. The insertion of human apolipoprotein H into phospholipid membranes: a monolayer study.

    PubMed

    Wang, S X; Cai, G P; Sui, S F

    1998-10-15

    Apolipoprotein H (ApoH) is a plasma glycoprotein isolated from human serum. The interactions of ApoH with lipid membrane were reported to be essential for its physiological and pathogenic roles. In this paper we studied the ability of ApoH to insert into phospholipid membranes using the monolayer approach. The results show that ApoH is surface active and can insert into the lipid monolayers. The insertion ability of ApoH is stronger when a higher content of negatively charged lipids is present in the membrane. The acidic-pH and low-ionic-strength conditions will also enhance ApoH insertion, but these factors may not have much influence on the final insertion ability of ApoH, suggesting that, in the mechanism of ApoH insertion, not only electrostatic forces, but also hydrophobic interactions, are evidently involved. Modification by heat inactivation and reduction/alkylation does not change the critical insertion pressure (pic) of ApoH, suggesting a stable domain, maybe a linear sequence motif, but not the native three-dimensional structure of ApoH, is responsible for its insertion. The extent to which insertion of ApoH into phospholipid membranes may facilitate the 'immune cleaning' of plasma liposomes is discussed.

  7. Two independent apolipoprotein a5 Haplotypes influence human plasma triglyceride levels

    SciTech Connect

    Pennacchio, Len A.; Olivier, Michael; Hubacek, Jaroslav A.; Krauss, Ronald M.; Rubin, Edward M.; Cohen, Jonathan C.

    2002-09-16

    The recently identified apolipoprotein A5 gene (APOA5) has been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. We previously identified an APOA5 haplotype (designated APOA5*2) that is present in {approx}16 percent of Caucasians and is associated with increased plasma triglyceride concentrations. In this report we describe another APOA5 haplotype (APOA5*3) containing the rare allele of the single nucleotide polymorphism c.56C>G that changes serine to tryptophan at codon 19 and is independently associated with high plasma triglyceride levels in three different populations. In a sample of 264 Caucasian men and women with plasma triglyceride concentrations above the 90th percentile or below the 10th percentile, the APOA5*3 haplotype was more than three-fold more common in the group with high plasma triglyceride levels. In a second independently ascertained sample of Caucasian men and women (n 1/4 419) who were studied while consuming their self-selected diets as well as after high-carbohydrate diets and high-fat diets, the APOA5*3 haplotype was associated with increased plasma triglyceride levels on all three dietary regimens. In a third population comprising 2660 randomly selected individuals, the APOA5*3 haplotype was found in 12 percent of Caucasians, 14 percent of African-Americans and 28 percent of Hispanics and was associated with increased plasma triglyceride levels in both men and women in each ethnic group. These findings establish that the APOA5 locus contributes significantly to inter-individual variation in plasma triglyceride levels in humans. Together, the APOA5*2 and APOA5*3 haplotypes are found in 25 50 percent of African-Americans, Hispanics and Caucasians and support the contribution of common human variation to quantitative phenotypes in the general population.

  8. Dietary fat elevates hepatic apoA-I production by increasing the fraction of apolipoprotein A-I mRNA in the translating pool.

    PubMed

    Azrolan, N; Odaka, H; Breslow, J L; Fisher, E A

    1995-08-25

    Elevated plasma high density lipoprotein cholesterol (HDL-C) levels are associated with a decreased risk for coronary heart disease. Ironically, diets enriched in saturated fat and cholesterol (HF/HC diets), which tend to accelerate atherosclerotic processes by increasing LDL cholesterol levels, also raise HDL-C. We have recently reported, using a human apoA-I (hapoA-1) transgenic mouse model, that the elevation of HDL-C by a HF/HC diet is attributable, in part, to an increase in the hepatic production of hapoA-1. To further define the hepatocellular processes associated with this induction, we have prepared primary hepatocytes from hapoA-1 transgenic mice. Rates of hapoA-1 secretion were 40% greater from cells prepared from animals fed the HF/HC relative to a low fat-low cholesterol (LF/LC) control diet. The abundance of hapoA-1 mRNA in these cells was similar between hepatocytes prepared from the HF/HC and LF/LC diet fed animals, suggesting a post-transcriptional mechanism that does not involve mRNA stability. Inhibition of secretion using brefeldin A revealed an increase in cellular hapoA-1 accumulation. Thus, the HF/HC diet apparently affects hepatic hapoA-1 production via a mechanism that is manifest prior to the exit of newly synthesized hapoA-1 from the Golgi. Pulse-chase experiments revealed a 39% greater peak hapoA-1 synthesis, with no difference in the degradation of total labeled hapoA-1 protein, as a result of the HF/HC diet feeding. Finally, resolution of liver S10 extracts via sucrose density sedimentation and metrizamide density equilibrium gradient centrifugation analyses both revealed similar increases (31 and 24%, respectively) in the relative percentage of hapoA-1 mRNA associated with the translating polysomal fractions as a result of the HF/HC feeding. Together, these data suggest that the HF/HC diet affects hepatic hapoA-1 production via a specific modulation in the relative amount of hapoA-1 mRNA in the polysomal pool. These observations

  9. Complex effects of inhibiting hepatic apolipoprotein B100 synthesis in humans

    PubMed Central

    Reyes-Soffer, Gissette; Moon, Byoung; Hernandez-Ono, Antonio; Dionizovik-Dimanovski, Marija; Jimenez, Jhonsua; Obunike, Joseph; Thomas, Tiffany; Ngai, Colleen; Fontanez, Nelson; Donovan, Daniel S.; Karmally, Wahida; Holleran, Stephen; Ramakrishnan, Rajasekhar; Mittleman, Robert S.; Ginsberg, Henry N.

    2016-01-01

    Mipomersen is a 20mer antisense oligonucleotide (ASO) that inhibits apolipoprotein B (apoB) synthesis; its low-density lipoprotein (LDL)–lowering effects should therefore result from reduced secretion of very-low-density lipoprotein (VLDL). We enrolled 17 healthy volunteers who received placebo injections weekly for 3 weeks followed by mipomersen weekly for 7 to 9 weeks. Stable isotopes were used after each treatment to determine fractional catabolic rates and production rates of apoB in VLDL, IDL (intermediate-density lipoprotein), and LDL, and of triglycerides in VLDL. Mipomersen significantly reduced apoB in VLDL, IDL, and LDL, which was associated with increases in fractional catabolic rates of VLDL and LDL apoB and reductions in production rates of IDL and LDL apoB. Unexpectedly, the production rates of VLDL apoB and VLDL triglycerides were unaffected. Small interfering RNA–mediated knockdown of apoB expression in human liver cells demonstrated preservation of apoB secretion across a range of apoB synthesis. Titrated ASO knockdown of apoB mRNA in chow-fed mice preserved both apoB and triglyceride secretion. In contrast, titrated ASO knockdown of apoB mRNA in high-fat–fed mice resulted in stepwise reductions in both apoB and triglyceride secretion. Mipomersen lowered all apoB lipoproteins without reducing the production rate of either VLDL apoB or triglyceride. Our human data are consistent with longstanding models of posttranscriptional and posttranslational regulation of apoB secretion and are supported by in vitro and in vivo experiments. Targeting apoB synthesis may lower levels of apoB lipoproteins without necessarily reducing VLDL secretion, thereby lowering the risk of steatosis associated with this therapeutic strategy. PMID:26819195

  10. Effects of apolipoproteins on the kinetics of cholesterol exchange

    SciTech Connect

    Letizia, J.Y.; Phillips, M.C. )

    1991-01-22

    The effects of apolipoproteins on the kinetics of cholesterol exchange have been investigated by monitoring the transfer of ({sup 14}C)cholesterol from donor phospholipid/cholesterol complexes containing human apolipoproteins A, B, or C. Negatively charged discoidal and vesicular particles containing purified apolipoproteins complexed with lipid and a trace of ({sup 14}C)cholesterol were incubated with a 10-fold excess of neutral, acceptor, small unilamellar vesicles. The donor and acceptor particles were separated by chromatogrphy of DEAE-Sepharose, and the rate of movement of labeled cholesterol was analyzed as a first-order exchange process. The kinetics of exchange of cholesterol from both vesicular and discoidal complexes that contain apoproteins are consistent with an aqueous diffusion mechanism, as has been established previously for PC/cholesterol SUV. Apolipoproteins A-I, A-II, reduced and carboxymethylated A-11, and B-100 present in SUV at the same lipid/protein (w/w) ratio all enhance the rate of cholesterol exchange to about the same degree. Cholesterol molecules exchange more rapidly from discoidal complexes. Generally, as the diameter of apoprotein/phospholipid/cholesterol discs decreases, t{sub 1/2} for cholesterol exchange decreases. Since small bilayer discs have a relatively high ratio of boundary to face surface area, cholesterol molecules desorb more rapidly than from larger discs. The modulation of lipid packing by the apoprotein molecules present at the surface of lipoprotein particles affects the rate of cholesterol exchange from such particles.

  11. Internet AIS

    NASA Astrophysics Data System (ADS)

    Filjar, Renato; Desic, Sasa; Pokrajac, Danijela; Cubic, Ivica

    2005-05-01

    Automatic Identification System (AIS) has recently become the leading issue in maritime navigation and traffic management worldwide. The present AIS solution, based on a VHF data communications scheme, provides AIS functionalities for SOLAS (AIS Class A) vessels only in a limited environment defined by radio propagation properties. Here we present a novel approach in AIS development based on current mobile communication technologies. It utilises existing mobile communications equipment that the majority of targetted end-users own and are familiar with. A novel AIS concept aims to offer a transition of AIS data traffic to mobile Internet. An innovative AIS architecture supports AIS data processing, storing and transferring to authorised parties. This enhances not only the operational area, but also provides the global AIS with data transfer security and an improved aids-for-navigation service, with all legally traceable vessels (both AIS Class A and AIS Class B) included in the system. In order to provide the development framework for Internet AIS, a set of essential four use-cases, a communication protocol and the first Internet AIS prototype have been recently developed and are briefly introduced in this article.

  12. Sequence Diversity and Large-Scale Typing of SNPs in the Human Apolipoprotein E Gene

    PubMed Central

    Nickerson, Deborah A.; Taylor, Scott L.; Fullerton, Stephanie M.; Weiss, Kenneth M.; Clark, Andrew G.; Stengård, Jari H.; Salomaa, Veikko; Boerwinkle, Eric; Sing, Charles F.

    2000-01-01

    A common strategy for genotyping large samples begins with the characterization of human single nucleotide polymorphisms (SNPs) by sequencing candidate regions in a small sample for SNP discovery. This is usually followed by typing in a large sample those sites observed to vary in a smaller sample. We present results from a systematic investigation of variation at the human apolipoprotein E locus (APOE), as well as the evaluation of the two-tiered sampling strategy based on these data. We sequenced 5.5 kb spanning the entire APOE genomic region in a core sample of 72 individuals, including 24 each of African-Americans from Jackson, Mississippi; European-Americans from Rochester, Minnesota; and Europeans from North Karelia, Finland. This sequence survey detected 21 SNPs and 1 multiallelic indel, 14 of which had not been previously reported. Alleles varied in relative frequency among the populations, and 10 sites were polymorphic in only a single population sample. Oligonucleotide ligation assays (OLA) were developed for 20 of these sites (omitting the indel and a closely-linked SNP). These were then scored in 2179 individuals sampled from the same three populations (n = 843, 884, and 452, respectively). Relative allele frequencies were generally consistent with estimates from the core sample, although variation was found in some populations in the larger sample at SNPs that were monomorphic in the corresponding smaller core sample. Site variation in the larger samples showed no systematic deviation from Hardy-Weinberg expectation. The large OLA sample clearly showed that variation in many, but not all, of OLA-typed SNPs is significantly correlated with the classical protein-coding variants, implying that there may be important substructure within the classical ɛ2, ɛ3, and ɛ4 alleles. Comparison of the levels and patterns of polymorphism in the core samples with those estimated for the OLA-typed samples shows how nucleotide diversity is underestimated when

  13. Plasma clearance of human low-density lipoprotein in human apolipoprotein B transgenic mice is related to particle diameter.

    PubMed

    Berneis, Kaspar; Shames, David M; Blanche, Patricia J; La Belle, Michael; Rizzo, Manfredi; Krauss, Ronald M

    2004-04-01

    To test for intrinsic differences in metabolic properties of low-density lipoprotein (LDL) as a function of particle size, we examined the kinetic behavior of 6 human LDL fractions ranging in size from 251 to 265 A injected intravenously into human apolipoprotein (apo) B transgenic mice. A multicompartmental model was formulated and fitted to the data by standard nonlinear regression using the Simulation, Analysis and Modeling (SAAM II) program. Smaller sized LDL particles (251 to 257 A) demonstrated a significantly slower fractional catabolic rate (FCR) (0.050 +/- 0.045 h(-1)) compared with particles of larger size (262 to 265 A) (0.134 +/- -0.015 h(-1), P <.03), and there was a significant correlation between FCR and the peak LDL diameter of the injected fractions (R(2) =.71, P <.034). The sum of the equilibration parameters, k(2,1) and k(1,2), for smaller LDL (0.255 h(-1) and 0.105 h(-1), respectively) was significantly smaller than that for larger LDL (0.277 h(-1) and 0.248 h(-1), respectively; P <.01), indicative of slower intravascular-extravascular exchange for smaller LDL. Therefore in this mouse model, smaller LDL particles are cleared more slowly from plasma than larger LDL and are exchanged more slowly with the extravascular space. This might be due to compositional or structural features of smaller LDL that lead to retarded clearance.

  14. The removal of cholesterol from aortic smooth muscle cells in culture and Landschutz ascites cells by fractions of human high-density apolipoprotein.

    PubMed

    Stein, Y; Glangeaud, M C; Fainaru, M; Stein, O

    1975-01-24

    Ascites cells were labeled by intraperitoneal injection of [3H]cholesterol and aortic smooth muscle cells by addition of [3H]cholesterol to the serum component of the culture medium. The release of cholesterol from cells into a serum-free medium supplemented with the various "acceptors" was studied using ascites cells in suspension and aortic smooth muscle cells in a multilayer culture. Unfractionated human high-density apolipoprotein was somewhat more effective in the removal of labeled cellular free cholesterol, in both cell types, than apolipoprotein derived from rat high-density lipoprotein. Following separation of human high-density apolipoprotein into four fractions by Sephadex chromatography, the effect of each fraction on the removal of cellular cholesterol from ascites cells was studied. The individual fractions had a lower capacity for cholesterol removal than the original unfractionated high-density apolipoprotein and the lowest activity was detected in Fraction II which comprised 75% of the total apolipoprotein. The effectiveness to remove cholesterol could be restored to all the fractions, as well as enhanced, by addition of sonicated suspensions of lecithin or sphingomyelin, which by themselves promoted a more limited removal of cellular cholesterol. Negatively stained preparations of mixtures of the four fractions and sonicated dispersion of lecithin were shown to consist of vesicles and discs of various sizes. Addition of the apolipoprotein fractions (especially Fractions II and IV) to sonicated dispersion of sphingomyelin resulted in a pronounced formation of discs which showed a high tendency towards stack formation. Mixtures of Fraction II and lecithin or sphingomyelin were effective in the release of cellular cholesterol from multilayers of aortic smooth muscle cells in culture. These results show the feasibility of net removal of cholesterol from cells which grow in a form resembling a tissue and thus provide a model to study the role of

  15. AI techniques for optimizing multi-objective reservoir operation upon human and riverine ecosystem demands

    NASA Astrophysics Data System (ADS)

    Tsai, Wen-Ping; Chang, Fi-John; Chang, Li-Chiu; Herricks, Edwin E.

    2015-11-01

    Flow regime is the key driver of the riverine ecology. This study proposes a novel hybrid methodology based on artificial intelligence (AI) techniques for quantifying riverine ecosystems requirements and delivering suitable flow regimes that sustain river and floodplain ecology through optimizing reservoir operation. This approach addresses issues to better fit riverine ecosystem requirements with existing human demands. We first explored and characterized the relationship between flow regimes and fish communities through a hybrid artificial neural network (ANN). Then the non-dominated sorting genetic algorithm II (NSGA-II) was established for river flow management over the Shihmen Reservoir in northern Taiwan. The ecosystem requirement took the form of maximizing fish diversity, which could be estimated by the hybrid ANN. The human requirement was to provide a higher satisfaction degree of water supply. The results demonstrated that the proposed methodology could offer a number of diversified alternative strategies for reservoir operation and improve reservoir operational strategies producing downstream flows that could meet both human and ecosystem needs. Applications that make this methodology attractive to water resources managers benefit from the wide spread of Pareto-front (optimal) solutions allowing decision makers to easily determine the best compromise through the trade-off between reservoir operational strategies for human and ecosystem needs.

  16. High- and low-temperature unfolding of human high-density apolipoprotein A-2.

    PubMed

    Gursky, O; Atkinson, D

    1996-09-01

    Human plasma apolipoprotein A-2 (apoA-2) is the second major protein of the high-density lipoproteins that mediate the transport and metabolism of cholesterol. Using CD spectroscopy and differential scanning calorimetry, we demonstrate that the structure of lipid-free apoA-2 in neutral low-salt solutions is most stable at approximately 25 degrees C and unfolds reversibly both upon heating and cooling from 25 degrees C. High-temperature unfolding of apoA-2, monitored by far-UV CD, extends from 25-85 degrees C with midpoint Th = 56 +/- 2 degrees C and vant Hoff's enthalpy delta H(Th) = 17 +/- 2 kcal/mol that is substantially lower than the expected enthalpy of melting of the alpha-helical structure. This suggests low-cooperativity apoA-2 unfolding. The apparent free energy of apoA-2 stabilization inferred from the CD analysis of the thermal unfolding, delta G(app)(25 degrees) = 0.82 +/- 0.15 kcal/mol, agrees with the value determined from chemical denaturation. Enhanced low-temperature stability of apoA-2 observed upon increase in Na2HPO4 concentration from 0.3 mM to 50 mM or addition of 10% glycerol may be linked to reduced water activity. The close proximity of the heat and cold unfolding transitions, that is consistent with low delta G(app)(25 degrees), indicates that lipid-free apoA-2 has a substantial hydrophobic core but is only marginally stable under near-physiological solvent conditions. This suggests that in vivo apoA-2 transfer is unlikely to proceed via the lipid-free state. Low delta H(Th) and low apparent delta Cp approximately 0.52 kcal/mol.K inferred from the far-UV CD analysis of apoA-2 unfolding, and absence of tertiary packing interactions involving Tyr groups suggested by near-UV CD, are consistent with a molten globular-like state of lipid-free apoA-2.

  17. Role of Conserved Proline Residues in Human Apolipoprotein A-IV Structure and Function*

    PubMed Central

    Deng, Xiaodi; Walker, Ryan G.; Morris, Jamie; Davidson, W. Sean; Thompson, Thomas B.

    2015-01-01

    Apolipoprotein (apo)A-IV is a lipid emulsifying protein linked to a range of protective roles in obesity, diabetes, and cardiovascular disease. It exists in several states in plasma including lipid-bound in HDL and chylomicrons and as monomeric and dimeric lipid-free/poor forms. Our recent x-ray crystal structure of the central domain of apoA-IV shows that it adopts an elongated helical structure that dimerizes via two long reciprocating helices. A striking feature is the alignment of conserved proline residues across the dimer interface. We speculated that this plays important roles in the structure of the lipid-free protein and its ability to bind lipid. Here we show that the systematic conversion of these prolines to alanine increased the thermodynamic stability of apoA-IV and its propensity to oligomerize. Despite the structural stabilization, we noted an increase in the ability to bind and reorganize lipids and to promote cholesterol efflux from cells. The novel properties of these mutants allowed us to isolate the first trimeric form of an exchangeable apolipoprotein and characterize it by small-angle x-ray scattering and chemical cross-linking. The results suggest that the reciprocating helix interaction is a common feature of all apoA-IV oligomers. We propose a model of how self-association of apoA-IV can result in spherical lipoprotein particles, a model that may have broader applications to other exchangeable apolipoprotein family members. PMID:25733664

  18. Apolipoprotein D is the major protein component in cyst fluid from women with human breast gross cystic disease.

    PubMed Central

    Balbín, M; Freije, J M; Fueyo, A; Sánchez, L M; López-Otín, C

    1990-01-01

    GCDFP(gross-cystic-disease-fluid protein)-24, a progesterone-binding protein present in large amounts in cyst fluid from human breast gross cystic disease, was purified in a one-step procedure by size-exclusion h.p.l.c. Peptide fragments obtained by trypsin digestion of the intact protein were purified by reverse-phase h.p.l.c. and analysed for their amino acid composition and subjected to automated Edman degradation. A search of the National Biomedical Research Foundation Data Bank revealed that all the sequenced tryptic peptides from protein GCDFP-24 matched perfectly with regions present in the amino acid sequence determined for human apolipoprotein D. Additional data on N-terminal sequence of the unblocked proteins, carbohydrate-attachment sites, amino acid composition and molecular-mass estimations supported the identity between both molecules. On the basis of this identity a possible role of apolipoprotein D in progesterone transport is proposed. Images Fig. 2. PMID:2244881

  19. C/EBP-β Is Differentially Affected by PPARα Agonists Fenofibric Acid and GW7647, But Does Not Change Apolipoprotein A-I Production During ER-Stress and Inflammation.

    PubMed

    van der Krieken, Sophie E; Popeijus, Herman E; Konings, Maurice; Dullens, Stefan P J; Mensink, Ronald P; Plat, Jogchum

    2017-04-01

    Increasing apolipoproteinA-I (apoA-I) production may be anti-atherogenic. Thus, there is a need to identify regulatory factors involved. Transcription of apoA-I involves peroxisome-proliferator-activated-receptor-alpha (PPARα) activation, but endoplasmic reticulum (ER) -stress and inflammation also influence apoA-I production. To unravel why PPARα agonist GW7647 increased apoA-I production compared to PPARα agonist fenofibric acid (FeAc) in human hepatocellular carcinoma (HepG2) and colorectal adenocarcinoma (CaCo-2) cells, gene expression profiles were compared. Microarray analyses suggested CCAAT/enhancer-binding-protein-beta (C/EBP-β) involvement in the FeAc condition. Therefore, C/EBP-β silencing and isoform-specific overexpression experiments were performed under ER-stressed, inflammatory and non-inflammatory conditions. mRNA expression of C/EBP-β, ATF3, NF-IL3 and GDF15 were upregulated by FeAc compared to GW7647 in both cell lines, while DDIT3 and DDIT4 mRNA were only upregulated in HepG2 cells. This ER-stress related signature was associated with decreased apoA-I secretion. After ER-stress induction by thapsigargin or FeAc addition, intracellular apoA-I concentrations decreased, while ER-stress marker expression (CHOP, XBP1s, C/EBP-β) increased. Cytokine addition increased intracellular C/EBP-β levels and lowered apoA-I concentrations. Although a C/EBP binding place is present in the apoA-I promoter, C/EBP-β silencing or isoform-specific overexpression did not affect apoA-I production in inflammatory, non-inflammatory and ER-stressed conditions. Therefore, C/EBP-β is not a target to influence hepatic apoA-I production. J. Cell. Biochem. 118: 754-763, 2017. © 2016 Wiley Periodicals, Inc.

  20. 18O proteomics reveal increased Human Apolipoprotein CIII in Hispanic HIV-1 positive women with HAART that use cocaine

    PubMed Central

    Zenón, Frances; Jorge, Inmaculada; Cruz, Ailed; Suarez, Erick; Segarra, Annabell C.; Vázquez, Jesús; Meléndez, Loyda M.; Serrano, Horacio

    2016-01-01

    Purpose Drug abuse is a major risk factor in the development and progression of HIV-1. This study defines the alterations in the plasma proteome of HIV-1 infected women that use cocaine. Experimental Design Plasma samples from 12 HIV-seropositive Hispanic women under antiretroviral therapy were selected for this study. Six sample pairs were matched between non-drug users and cocaine users. After IgG and albumin depletion, SDS-PAGE, and in-gel digestion, peptides from non-drug users and cocaine users were labeled with 16O and 18O respectively and subjected to LC-MS/MS and quantitation using Proteome Discover and QuiXoT softwares and validated by ELISA. Results A total of 1,015 proteins were identified at 1% FDR. Statistical analyses revealed 13 proteins with significant changes between the two groups, cocaine and non-cocaine users (p<0.05). The great majority pertained to protection defense function and the rest pertained to transport, homeostatic, regulation, and binding of ligands. Apolipoprotein CIII was increased in plasma of HIV+ Hispanic women positive for cocaine compared to HIV+ non-drug users (p<0.05). Conclusions and clinical relevance Increased human Apolipoprotein CIII warrants that these patients be carefully monitored to avoid the increased risk of cardiovascular events associated with HIV, HAART and cocaine use. PMID:26255783

  1. Inhibition of radical reaction of apolipoprotein B-100 and alpha-tocopherol in human plasma by green tea catechins.

    PubMed

    Hashimoto, R; Yaita, M; Tanaka, K; Hara, Y; Kojo, S

    2000-12-01

    (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin gallate (EGCg), and Trolox inhibited the decreases of apolipoprotein B-100 (apoB) and alpha-tocopherol in a radical reaction of human plasma initiated by Cu(2+). The concentrations of EC, EGC, ECg, EGCg, and Trolox for 50% inhibition (IC50) of apoB fragmentation were 39.1, 42.2, 14.6, 21.3, and 36.2 microM, respectively. Similar IC50 values were observed for alpha-tocopherol consumption, indicating the close relationship between apoB fragmentation and alpha-tocopherol consumption. These results demonstrate that tea catechins serve as an effective antioxidant in plasma and that the gallate group has a strong antioxidative activity.

  2. Apolipoprotein distribution in human lipoproteins separated by polyacrylamide gradient gel electrophoresis.

    PubMed

    Vézina, C A; Milne, R W; Weech, P K; Marcel, Y L

    1988-05-01

    The heterogeneity of serum lipoproteins (excluding very low density (VLDL) and intermediate density (IDL) lipoproteins) and that of lipoproteins secreted by HepG2 cells has been studied by immunoblot analysis of the apolipoprotein composition of the particles separated by polyacrylamide gradient gel electrophoresis (GGE) under nondenaturing conditions. The reactions of antibodies to apoA-I, apoA-II, apoE, apoB, apoD, and apoA-IV have revealed discrete bands of particles which differ widely in size and apolipoprotein composition. GGE of native serum lipoproteins demonstrated that apoA-II is present in lipoproteins of limited size heterogeneity (apparent molecular mass 345,000 to 305,000) and that apoB is present in low density lipoproteins (LDL) and absent from all smaller or denser lipoproteins. In contrast, serum apoA-I, E, D, and A-IV are present in very heterogeneous particles. Serum apoA-I is present mainly in particles of 305 to 130 kDa where it is associated with apoA-II, and in decreasing order of immunoreactivity in particles of 130-90 kDa, 56 kDa, 815-345 kDa, and finally within the size range of LDL, all regions where there is little detectable apoA-II. Serum apoE is present in three defined fractions, one within the size range of LDL, one containing heterogeneous particles between 640 and 345 kDa, and one defined fraction at 96 kDa. Serum apoD is also present in three defined fractions, one comigrating with LDL, one containing heterogeneous particles between 390 and 150 kDa, and one band on the migration front. Most of serum apoA-IV is contained in a band comigrating with albumin. GGE of centrifugally prepared LDL shows the presence of apoB, apoE, and apoD, but not that of apoA-I. However, the particles containing apoA-I, which, in serum, migrated within the LDL size range and as bands of 815 to 345 kDa, were recovered upon centrifugation in the d greater than 1.21 g/ml fraction. GGE of high density lipoproteins (HDL) indicated that most of apoA-I, A

  3. Brazil nut ingestion increased plasma selenium but had minimal effects on lipids, apolipoproteins, and high-density lipoprotein function in human subjects.

    PubMed

    Strunz, Célia C; Oliveira, Tatiane V; Vinagre, Juliana C M; Lima, Adriana; Cozzolino, Silvia; Maranhão, Raul C

    2008-03-01

    The Brazil nut (Bertholletia excelsa) of the Amazon region is consumed worldwide. It is rich in both monounsaturated fatty acids and polyunsaturated fatty acids and is known for its high selenium content. This study tested the hypothesis whether the consumption of this nut could affect the plasma lipids and apolipoproteins and some functional properties of the antiatherogenic high-density lipoprotein (HDL). Fifteen normolipidemic subjects aged 27.3 +/- 3.9 years and with body mass index of 23.8 +/- 2.8 kg/m(2) consumed 45 g of Brazil nuts per day during a 15-day period. On days 0 and 15, blood was collected for biochemical analysis, determination of HDL particle size, paraoxonase 1 activity, and lipid transfer from a lipoprotein-like nanoparticle to the HDL fraction. Brazil nut ingestion did not alter HDL, low-density lipoprotein cholesterol, triacylglycerols, apolipoprotein A-I, or apolipoprotein B concentrations. HDL particle diameter and the activity of antioxidative paraoxonase 1, mostly found in the HDL fraction, were also unaffected. Supplementation increased the reception of cholesteryl esters (P < .05) by the HDL yet did not alter the reception of phospholipids, free cholesterol, or triacylglycerols. As expected, plasma selenium was significantly increased. However, the consumption of Brazil nuts for short duration by normolipidemic subjects in comparable amounts to those tested for other nuts did not alter serum lipid profile. The only alteration in HDL function was the increase in cholesteryl ester transfer. This latter finding may be beneficial because it would improve the nonatherogenic reverse cholesterol transport pathway.

  4. Biosynthesis of high density lipoprotein by chicken liver: intracellular transport and proteolytic processing of nascent apolipoprotein A-1

    PubMed Central

    1985-01-01

    To study the in vivo processing and secretion of Apolipoprotein A-I (Apo A-I), young chickens were administered individual L-[3H]amino acids intravenously and the time of intracellular transport of nascent Apo A-I from rough endoplasmic reticulum (RER) to the Golgi apparatus was measured. Within 3 to 9 min there was maximal incorporation of radioactivity into Apo A-I in both the RER and the Golgi cell fractions. By contrast, the majority of radioactive albumin was also present in the RER by 3 to 9 min, but did not reach peak amounts in the Golgi fraction until 9 to 25 min. Both radioactive Apo A-I and albumin appeared in the blood at about the same time (between 20 and 30 min). NH2-terminal amino acid sequence analysis of nascent intracellular Apo A-I showed that it contains a pro-hexapeptide extension identical to that of human Apo A-I. After 30 min of administration of radioactive amino acids radioactive Apo A-I was isolated by immunoprecipitation from the liver and serum. NH2-terminal sequence analysis of 20 amino acids indicated that chicken liver contained an equal mixture of nascent pro-Apo A-I and fully processed Apo A-I, whereas the serum only contained processed Apo A-I. Further studies showed that the RER only contained pro-Apo A-I, whereas a mixture of pro-Apo A-I and processed Apo A-I was found in the Golgi complex. These results indicate that, in chicken hepatocytes, there is a more rapid transport of Apo A-I than of albumin from the RER to the Golgi cell fractions, and that Apo A-I remains in the Golgi apparatus for a longer period of time before it is secreted into the blood. In addition these studies show that the in vivo proteolytic processing of chicken pro-Apo A-I to Apo A-I occurs in the Golgi cell fractions. PMID:3930506

  5. Mechanism of lipid lowering in mice expressing human apolipoprotein A5

    SciTech Connect

    Fruchart-Najib, Jamila; Bauge, Eric; Niculescu, Loredan-Stefan; Pham, Tatiana; Thomas, Benoit; Rommens, Corinne; Majd, Zouher; Brewer, Bryan; Rubin, Edward M.; Pennacchio, Len A.; Fruchart, Jean-Charles

    2004-01-15

    Recently, we reported that apoAV plays key role in triglycerides lowering. Here, we attempted to determine the mechanism underlying this hypotriglyceridemic effect. We showed that triglyceride turnover is faster in hAPOA5 transgenic compared to wild type mice. Moreover, both apoB and apoCIII are decreased and LPL activity is increased in postheparin plasma of hAPOA5 transgenic mice. These data suggest a decrease in size and number of VLDL. To further investigate the mechanism of hAPOA5 in hyperlipidemic background, we intercrossed hAPOA5 and hAPOC3 transgenic mice. The effect resulted in a marked decreased of VLDL triglyceride, cholesterol, apolipoproteins B and CIII. In postprandial state, the triglyceride response is abolished in hAPOA5 transgenic mice. We demonstrated that in response to the fat load in hAPOA5XhAPOC3 mice, apoAV shifted from HDL to VLDL, probably to limit the elevation of triglycerides. In vitro, apoAV activates lipoprotein lipase. However, apoAV does not interact with LPL but interacts physically with apoCIII. This interaction does not seem to displace apoCIII from VLDL but may induce conformational change in apoCIII and consequently change in its function leading the activation of lipoprotein lipase.

  6. Human apolipoprotein E ɛ4 expression impairs cerebral vascularization and blood–brain barrier function in mice

    PubMed Central

    Alata, Wael; Ye, Yue; St-Amour, Isabelle; Vandal, Milène; Calon, Frédéric

    2015-01-01

    Human apolipoprotein E (APOE) exists in three isoforms ɛ2, ɛ3, and ɛ4, of which APOE4 is the main genetic risk factor of Alzheimer's disease (AD). As cerebrovascular defects are associated with AD, we tested whether APOE genotype has an impact on the integrity and function of the blood–brain barrier (BBB) in human APOE-targeted replacement mice. Using the quantitative in situ brain perfusion technique, we first found lower (13.0% and 17.0%) brain transport coefficient (Clup) of [3H]-diazepam in APOE4 mice at 4 and 12 months, compared with APOE2 and APOE3 mice, reflecting a decrease in cerebral vascularization. Accordingly, results from immunohistofluorescence experiments revealed a structurally reduced cerebral vascularization (26% and 38%) and thinner basement membranes (30% and 35%) in 12-month-old APOE4 mice compared with APOE2 and APOE3 mice, suggesting vascular atrophy. In addition, APOE4 mice displayed a 29% reduction in [3H]-d-glucose transport through the BBB compared with APOE2 mice without significant changes in the expression of its transporter GLUT1 in brain capillaries. However, an increase of 41.3% of receptor for advanced glycation end products (RAGE) was found in brain capillaries of 12-month-old APOE4 mice. In conclusion, profound divergences were observed between APOE genotypes at the cerebrovascular interface, suggesting that APOE4-induced BBB anomalies may contribute to AD development. PMID:25335802

  7. Intravenously Injected Human Apolipoprotein A‐I Rapidly Enters the Central Nervous System via the Choroid Plexus

    PubMed Central

    Stukas, Sophie; Robert, Jerome; Lee, Michael; Kulic, Iva; Carr, Michael; Tourigny, Katherine; Fan, Jianjia; Namjoshi, Dhananjay; Lemke, Kalistyne; DeValle, Nicole; Chan, Jeniffer; Wilson, Tammy; Wilkinson, Anna; Chapanian, Rafi; Kizhakkedathu, Jayachandran N.; Cirrito, John R.; Oda, Michael N.; Wellington, Cheryl L.

    2014-01-01

    Background Brain lipoprotein metabolism is dependent on lipoprotein particles that resemble plasma high‐density lipoproteins but that contain apolipoprotein (apo) E rather than apoA‐I as their primary protein component. Astrocytes and microglia secrete apoE but not apoA‐I; however, apoA‐I is detectable in both cerebrospinal fluid and brain tissue lysates. The route by which plasma apoA‐I enters the central nervous system is unknown. Methods and Results Steady‐state levels of murine apoA‐I in cerebrospinal fluid and interstitial fluid are 0.664 and 0.120 μg/mL, respectively, whereas brain tissue apoA‐I is ≈10% to 15% of its levels in liver. Recombinant, fluorescently tagged human apoA‐I injected intravenously into mice localizes to the choroid plexus within 30 minutes and accumulates in a saturable, dose‐dependent manner in the brain. Recombinant, fluorescently tagged human apoA‐I accumulates in the brain for 2 hours, after which it is eliminated with a half‐life of 10.3 hours. In vitro, human apoA‐I is specifically bound, internalized, and transported across confluent monolayers of primary human choroid plexus epithelial cells and brain microvascular endothelial cells. Conclusions Following intravenous injection, recombinant human apoA‐I rapidly localizes predominantly to the choroid plexus. Because apoA‐I mRNA is undetectable in murine brain, our results suggest that plasma apoA‐I, which is secreted from the liver and intestine, gains access to the central nervous system primarily by crossing the blood–cerebrospinal fluid barrier via specific cellular mediated transport, although transport across the blood–brain barrier may also contribute to a lesser extent. PMID:25392541

  8. Susceptibility of Mice to Trypanosoma evansi Treated with Human Plasma Containing Different Concentrations of Apolipoprotein L-1

    PubMed Central

    Fanfa, Vinicius R.; Otto, Mateus A.; Gressler, Lucas T.; Tavares, Kaio C.S.; Lazzarotto, Cícera R.; Tonin, Alexandre A.; Miletti, Luiz C.; Duarte, Marta M.M.F.; Monteiro, Silvia G.

    2011-01-01

    The aim of this study was to test the susceptibility of mice to Trypanosoma evansi treated with human plasma containing different concentrations of apolipoprotein L-1 (APOL1). For this experiment, a strain of T. evansi and human plasma (plasmas 1, 2, and 3) from 3 adult males clinically healthy were used. In vivo test used 50 mice divided in 5 groups (A to E) with 10 animals in each group. Animals of groups B to E were infected, and then treated with 0.2 ml of human plasma in the following outline: negative control (A), positive control (B), treatment with plasma 1 (C), treatment with plasma 2 (D), and treatment with plasma 3 (E). Mice treated with human plasma showed an increase in longevity of 40.9±0.3 (C), 20±9.0 (D) and 35.6±9.3 (E) days compared to the control group (B) which was 4.3±0.5 days. The number of surviving mice and free of the parasite (blood smear and PCR negative) at the end of the experiment was 90%, 0%, and 60% for groups C, D, and E, respectively. The quantification of APOL1 was performed due to the large difference in the treatments that differed in the source plasma. In plasmas 1, 2, and 3 was detected the concentration of 194, 99, and 115 mg/dl of APOL1, respectively. However, we believe that this difference in the treatment efficiency is related to the level of APOL1 in plasmas. PMID:22355213

  9. Modification by acrolein, a component of tobacco smoke and age-related oxidative stress, mediates functional impairment of human apolipoprotein E.

    PubMed

    Tamamizu-Kato, Shiori; Wong, Jason Yiu; Jairam, Vikram; Uchida, Koji; Raussens, Vincent; Kato, Hiroyuki; Ruysschaert, Jean-Marie; Narayanaswami, Vasanthy

    2007-07-17

    Oxidative damage to proteins such as apolipoprotein B-100 increases the atherogenicity of low-density lipoproteins (LDL). However, little is known about the potential oxidative damage to apolipoprotein E (apoE), an exchangeable antiatherogenic apolipoprotein. ApoE plays an integral role in lipoprotein metabolism by regulating the plasma cholesterol and triglyceride levels. Hepatic uptake of lipoproteins is facilitated by apoE's ability to bind with cell surface heparan sulfate proteoglycans and to lipoprotein receptors via basic residues in its 22 kDa N-terminal domain (NT). We investigated the effect of acrolein, an aldehydic product of endogenous lipid peroxidation and a tobacco smoke component, on the conformation and function of recombinant human apoE3-NT. Acrolein caused oxidative modification of apoE3-NT as detected by Western blot with acrolein-lysine-specific antibodies, and tertiary conformational alterations. Acrolein modification impairs the ability of apoE3-NT to interact with heparin and the LDL receptor. Furthermore, acrolein-modified apoE3-NT displayed a 5-fold decrease in its ability to interact with lipid surfaces. Our data indicate that acrolein disrupts the functional integrity of apoE3, which likely interferes with its role in regulating plasma cholesterol homeostasis. These observations have implications regarding the role of apoE in the pathogenesis of smoking- and oxidative stress-mediated cardiovascular and cerebrovascular diseases.

  10. Complement Factor H Binds to Human Serum Apolipoprotein E and Mediates Complement Regulation on High Density Lipoprotein Particles.

    PubMed

    Haapasalo, Karita; van Kessel, Kok; Nissilä, Eija; Metso, Jari; Johansson, Tiira; Miettinen, Sini; Varjosalo, Markku; Kirveskari, Juha; Kuusela, Pentti; Chroni, Angelika; Jauhiainen, Matti; van Strijp, Jos; Jokiranta, T Sakari

    2015-11-27

    The alternative pathway of complement is an important part of the innate immunity response against foreign particles invading the human body. To avoid damage to host cells, it needs to be efficiently down-regulated by plasma factor H (FH) as exemplified by various diseases caused by mutations in its domains 19-20 (FH19-20) and 5-7 (FH5-7). These regions are also the main interaction sites for microbial pathogens that bind host FH to evade complement attack. We previously showed that inhibition of FH binding by a recombinant FH5-7 construct impairs survival of FH binding pathogens in human blood. In this study we found that upon exposure to full blood, the addition of FH5-7 reduces survival of, surprisingly, also those microbes that are not able to bind FH. This effect was mediated by inhibition of complement regulation and subsequently enhanced neutrophil phagocytosis by FH5-7. We found that although FH5-7 does not reduce complement regulation in the actual fluid phase of plasma, it reduces regulation on HDL particles in plasma. Using affinity chromatography and mass spectrometry we revealed that FH interacts with serum apolipoprotein E (apoE) via FH5-7 domains. Furthermore, binding of FH5-7 to HDL was dependent on the concentration of apoE on the HDL particles. These findings explain why the addition of FH5-7 to plasma leads to excessive complement activation and phagocytosis of microbes in full anticoagulated blood. In conclusion, our data show how FH interacts with apoE molecules via domains 5-7 and regulates alternative pathway activation on plasma HDL particles.

  11. “Sticky” and “Promiscuous”—the Yin and Yang of Apolipoprotein A-I Termini in Discoidal High Density Lipoproteins: A Combined Computational-Experimental Approach†

    PubMed Central

    Jones, Martin K.; Gu, Feifei; Catte, Andrea; Li, Ling; Segrest, Jere P.

    2011-01-01

    Apolipoprotein (apo) A-I-containing lipoproteins in the form of high density lipoproteins (HDL) are inversely correlated with atherosclerosis. Because HDL is a soft form of condensed matter easily deformable by thermal fluctuations, the molecular mechanisms for HDL remodeling are not well understood. A promising approach to understanding HDL structure and dynamics is molecular dynamics (MD). In the present study, two computational strategies, MD simulated annealing (MDSA) and MD temperature-jump, were combined with experimental particle reconstitution to explore molecular mechanisms for phospholipid (PL)-rich HDL particle remodeling. The N-terminal domains of full length apoA-I were shown to be “sticky”, acting as a molecular latch largely driven by salt bridges, until, at a critical threshold of particle size, the associated domains released to expose extensive hydrocarbon regions of the PL to solvent. The “sticky” N-termini also associate with other apoA-I domains, perhaps being involved in N-terminal loops suggested by other laboratories. Alternatively, the overlapping helix 10 C-terminal domains of apoA-I were observed to be extremely mobile or “promiscuous”, transiently exposing limited hydrocarbon regions of PL. Based upon these models and reconstitution studies, we propose that separation of the N-terminal domains, as particles exceed a critical size, trigger fusion between particles or between particles and membranes, while the C-terminal domains of apoA-I drive the exchange of polar lipids down concentration gradients between particles. This hypothesis has significant biological relevance since lipid exchange and particle remodeling are critically important processes during metabolism of HDL particles at every step in the anti-atherogenic process of reverse cholesterol transport. PMID:21329368

  12. An efficient on-column expressed protein ligation strategy: Application to segmental triple labeling of human apolipoprotein E3

    PubMed Central

    Zhao, Wentao; Zhang, Yonghong; Cui, Chunxian; Li, Qianqian; Wang, Jianjun

    2008-01-01

    Expressed protein ligation (EPL) is an intein-based approach that has been used for protein engineering and biophysical studies of protein structures. One major problem of the EPL is the low yield of final ligation product, primarily due to the complex procedure of the EPL, preventing EPL from gaining popularity in the research community. Here we report an efficient on-column EPL strategy, which focuses on enhancing the expression level of the intein-fusion protein that generates thioester for the EPL. We applied this EPL strategy to human apolipoprotein E (apoE) and routinely obtained 25–30 mg segmental, triple-labeled apoE from 1-L cell culture. The approaches reported here are general approaches that are not specific for apoE, thus providing a general strategy for a highly efficient EPL. In addition, we also report an isotopic labeling scheme that double-labels one domain and keeps the other domain of apoE deuterated. Such an isotopic labeling scheme can only be achieved using the EPL strategy. Our data indicated that the segmental triple-labeled apoEs using this labeling scheme produced high-quality, simplified NMR spectra, facilitating NMR spectral assignment. For large proteins, such as apoE, perdeuterated protein samples have to be used to reduce the linewidth of NMR signals, causing a major problem for the NOE-based NMR method, since perdeuterated proteins lack protons for NOE measurement. The new labeling strategy solves this problem and provides 13C/15N double-labeled, protonated protein domains, allowing for determination of high-resolution NMR structure of these large proteins. PMID:18305193

  13. Role of apolipoprotein E in febrile convulsion.

    PubMed

    Giray, Ozlem; Ulgenalp, Ayfer; Bora, Elçin; Uran, Nedret; Yilmaz, Ebru; Unalp, Aycan; Erçal, Derya

    2008-10-01

    Apolipoprotein E is consistently associated with the progression of some common human neurodegenerative diseases, e.g., epilepsy. We hypothesized that genetic variations in the apolipoprotein E gene have implications for susceptibility to, and prognoses in, febrile convulsion, which plays an apparent role in the development of epilepsy. We used the polymerase chain reaction and restriction enzyme digestion to characterize variations of the apolipoprotein E gene. Sixty-nine patients with febrile convulsion (simple/complex) and a corresponding cohort of healthy patients (n = 75) were used. There was no significant difference in genotypic distribution and allelic frequencies of the apolipoprotein E gene between the febrile convulsion and control groups. Comparing subpopulations of the febrile convulsion group (patients with simple and complex febrile convulsion), we noted that no patients with the epsilon3/epsilon4 genotype had complex febrile convulsions. The apolipoprotein E epsilon3/epsilon4 genotype was more frequently seen in the simple febrile than in the complicated febrile convulsion group (9 versus 0 patients, respectively). The data indicate an association with the epsilon3/epsilon4 genotype of the apolipoprotein E gene with a milder phenotype. Although apolipoprotein E4 is not a vulnerability factor regarding febrile convulsions, it seems effective in regard to prognoses.

  14. Antisense inhibition of apolipoprotein (a) to lower plasma lipoprotein (a) levels in humans

    PubMed Central

    Graham, Mark J.; Viney, Nick; Crooke, Rosanne M.; Tsimikas, Sotirios

    2016-01-01

    Epidemiological, genetic association, and Mendelian randomization studies have provided strong evidence that lipoprotein (a) [Lp(a)] is an independent causal risk factor for CVD, including myocardial infarction, stroke, peripheral arterial disease, and calcific aortic valve stenosis. Lp(a) levels >50 mg/dl are highly prevalent (20% of the general population) and are overrepresented in patients with CVD and aortic stenosis. These data support the notion that Lp(a) should be a target of therapy for CVD event reduction and to reduce progression of aortic stenosis. However, effective therapies to specifically reduce plasma Lp(a) levels are lacking. Recent animal and human studies have shown that Lp(a) can be specifically targeted with second generation antisense oligonucleotides (ASOs) that inhibit apo(a) mRNA translation. In apo(a) transgenic mice, an apo(a) ASO reduced plasma apo(a)/Lp(a) levels and their associated oxidized phospholipid (OxPL) levels by 86 and 93%, respectively. In cynomolgus monkeys, a second generation apo(a) ASO, ISIS-APO(a)Rx, significantly reduced hepatic apo(a) mRNA expression and plasma Lp(a) levels by >80%. Finally, in a phase I study in normal volunteers, ISIS-APO(a)Rx ASO reduced Lp(a) levels and their associated OxPL levels up to 89 and 93%, respectively, with minimal effects on other lipoproteins. ISIS-APO(a)Rx represents the first specific and potent drug in clinical development to lower Lp(a) levels and may be beneficial in reducing CVD events and progression of calcific aortic valve stenosis. PMID:26538546

  15. Real time magnetic resonance imaging of apo AI metabolism in vivo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Apolipoprotein AI (apo AI) plays a key role in maintaining cardiovascular health and constitutes the major lipoprotein component in high density lipoproteins (HDL). It metabolism, however, follows a complex pathway. Synthesized in the liver and intestines, its becomes lipidated by its interaction w...

  16. Human factors involvement in bringing the power of AI to a heterogeneous user population

    NASA Technical Reports Server (NTRS)

    Czerwinski, Mary; Nguyen, Trung

    1994-01-01

    The Human Factors involvement in developing COMPAQ QuickSolve, an electronic problem-solving and information system for Compaq's line of networked printers, is described. Empowering customers with expert system technology so they could solve advanced networked printer problems on their own was a major goal in designing this system. This process would minimize customer down-time, reduce the number of phone calls to the Compaq Customer Support Center, improve customer satisfaction, and, most importantly, differentiate Compaq printers in the marketplace by providing the best, and most technologically advanced, customer support. This represents a re-engineering of Compaq's customer support strategy and implementation. In its first generation system, SMART, the objective was to provide expert knowledge to Compaq's help desk operation to more quickly and correctly answer customer questions and problems. QuickSolve is a second generation system in that customer support is put directly in the hands of the consumers. As a result, the design of QuickSolve presented a number of challenging issues. Because the produce would be used by a diverse and heterogeneous set of users, a significant amount of human factors research and analysis was required while designing and implementing the system. Research that shaped the organization and design of the expert system component as well.

  17. Analytical isoelectric focusing of apolipoprotein B of human plasma low-density lipoproteins in the presence of a nonionic and a zwitterionic detergent.

    PubMed

    Melnik, B C; Melnik, S F

    1988-06-01

    A method for the analytical isoelectric focusing of Nonidet-P40-delipidated apolipoprotein B of human plasma low-density lipoproteins has been developed. Isoelectric focusing was performed in the presence of the zwitterionic nondenaturing detergent Chaps, 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate, and the nonionic surfactant Nonidet-P40, polyoxyethyleneglycol p-t-octylphenol with a mean of 9.0 ethylene oxide units per molecule. Low-density lipoprotein (LDL) apolipoprotein B (apo-B) entered 3.75% polyacrylamide gels without precipitation at the sites of sample application, permitting apoprotein recoveries of greater than 90% in the migrating bands. LDL apo-B exhibited 10 distinguishable bands with apparent isoelectric points of 7.34 (band 1), 7.27 (band 2), 7.16 (band 3), 7.02 (band 4), 6.88 (band 5), 6.70 (band 6), 6.61 (band 7), 6.48 (band 8), 6.40 (band 9), and 6.24 (band 10), respectively. Bands 3 and 4, 6 and 7, as well as 8 and 9 could be identified as major double bands. When the focused apo-B was run in a second dimension by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the same relative molecular weight of B-100 was obtained for all focused bands. After electrotransfer to nitrocellulose paper, all bands reacted with polyclonal anti-human LDL antibody. Furthermore, the detergent-solubilized apo-B retained the immunological properties of native low-density lipoproteins when tested by double immunodiffusion against polyvalent anti-human LDL sera.

  18. Targeting nanodisks via a single chain variable antibody - Apolipoprotein chimera

    SciTech Connect

    Iovannisci, David M.; Beckstead, Jennifer A.; Ryan, Robert O.

    2009-02-06

    Nanodisks (ND) are nanometer scale complexes of phospholipid and apolipoprotein that have been shown to function as drug delivery vehicles. ND harboring significant quantities of the antifungal agent, amphotericin B, or the bioactive isoprenoid, all trans retinoic acid, have been generated and characterized. As currently formulated, ND possess limited targeting capability. In this study, we constructed a single chain variable antibody (scFv).apolipoprotein chimera and assessed the ability of this fusion protein to form ND and recognize the antigen to which the scFv is directed. Data obtained revealed that {alpha}-vimentin scFv.apolipoprotein A-I is functional in ND formation and antigen recognition, opening the door to the use of such chimeras in targeting drug-enriched ND to specific tissues.

  19. Conformational studies of the N-terminal lipid-associating domain of human apolipoprotein C-I by CD and 1H NMR spectroscopy.

    PubMed Central

    Rozek, A.; Buchko, G. W.; Kanda, P.; Cushley, R. J.

    1997-01-01

    A peptide comprising the N-terminal 38 residues of human apolipoprotein C-I (apoC-I(1-38)) was synthesized using solid-phase methods and its solution conformation studied by CD and 1H NMR spectroscopy. The CD data indicate that apoC-I(1-38) has a similar helical content (55%) in the presence of saturating amounts of SDS or egg yolk lysophosphatidylcholine. A structural ensemble of SDS-bound apoC-I(1-38) was calculated from 464 NOE-based distance restraints using distance geometry methods. ApoC-I(1-38) adopts a helical structure between residues V4 and K30 and an extended C-terminus from Q31 when associated with SDS. The region K12-G15 undergoes slow conformational exchange as indicated by above-average amide resonance linewidths, large temperature coefficients, and fast exchange (< 2 h) of backbone amide protons with deuterium. The mobility of K12-G15 is reflected in the poorly defined dihedral angles of K12 and E13 in the calculated ensemble of structures. The average structure of apoC-I(1-38) is curved toward its hydrophobic face with bends of 125 degrees, centered at K12/E13, and 150 degrees, centered at K21. This curvature appears to be driven by the interaction of two hydrophobic clusters, one formed by residues L8, L11, F14, and L18, and the other by L25, I26, and I29, with the amphiphile SDS. Based on our present structural definition of apoC-I(1-38) and the previously obtained structure of the fragment apoC-I(35-53), we propose the secondary structure of intact apolipoprotein C-I. PMID:9300485

  20. Clinical significance of apolipoprotein A5

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have investigated the evidence from recent human studies examining the role of apolipoprotein A-V (APOA-V) in triglyceride-rich lipoprotein metabolism and cardiovascular disease (CVD) risk. Special emphasis was placed on the evidence emerging from the association between genetic variability at th...

  1. Baculovirus-mediated expression of human apolipoprotein E in Manduca sexta larvae generates particles that bind to the low density lipoprotein receptor.

    PubMed Central

    Gretch, D G; Sturley, S L; Friesen, P D; Beckage, N E; Attie, A D

    1991-01-01

    Human apolipoprotein E (apoE) is a ligand for the low density lipoprotein (LDL) receptor and mediates the catabolism of several classes of lipoprotein particles. Binding of apoE to the LDL receptor requires association of apoE with lipid in a vesicle or a lipoprotein particle. Because of this requirement, purified apoE or apoE derived directly from bacterial expression systems does not bind to the LDL receptor. To overcome this problem and to facilitate analysis of apoE structure, recombinant baculoviruses containing the human apoE cDNA fused to the polyhedrin promoter of Autographa californica nuclear polyhedrosis virus were constructed. The recombinant viruses were used to infect larvae of the tobacco hornworm Manduca sexta in vivo. High levels of lipoprotein particles containing human apoE were present in the hemolymph of infected larvae. In contrast to apoE produced by recombinant baculovirus-infected insect cells in vitro, these particles were excellent ligands for the LDL receptor. Images PMID:1924311

  2. Characterization of five new mutants in the carboxyl-terminal domain of human apolipoprotein E: No cosegregation with severe hyperlipidemia

    SciTech Connect

    Maagdenberg, A.M.J.M. van den; Bruijn, I.H. de; Hofker, M.H.; Frants, R.R. ); Knijff, P. de; Smelt, A.H.M.; Leuven, J.A.G.; van't Hooft, F.; Assmann, G.; Havekes, L.M. ); Weng, Wei; Funke, H. )

    1993-05-01

    Assessment of the apolipoprotein E (apoE) phenotype by isoelectric focusing of both hyperlipidemic and normolipidemic individuals identified five new variants. All mutations were confined to the downstream part of the APOE gene by using denaturing gradient gel electrophoresis (DGGE). Sequence analysis revealed five new mutations causing unique amino acid substitutions in the carboxyl-terminal part of the protein containing the putative lipid-binding domain. Three hyperlipoproteinemic probands were carriers of the APOE*2(Va1236[r arrow]Glu) allele, the APOE*3(Cys112-Arg; Arg251[r arrow]Gly) allele, or the APOE*1(Arg158[r arrow]Cys; Leu252[r arrow]Glu) allele. DGGE of the region encoding the receptor-binding domain was useful for haplotyping the mutations at codons 112 and 158. Family studies failed to demonstrate cosegregation between the new mutations and severe hyperlipoproteinemia, although a number of carriers for the APOE*3(Cys112[r arrow]Arg; Arg251[r arrow]Gly) allele and the APOE*1(Arg158-Cys; Leu252[r arrow]Glu) allele expressed hypertriglyceridemia and/ or hypercholesterolemia. Two other mutant alleles, APOE*4[sup [minus

  3. Sesamin attenuates intercellular cell adhesion molecule-1 expression in vitro in TNF-alpha-treated human aortic endothelial cells and in vivo in apolipoprotein-E-deficient mice.

    PubMed

    Wu, Wen-Huey; Wang, Shu-Huei; Kuan, I-I; Kao, Ya-Shi; Wu, Pei-Jhen; Liang, Chan-Jung; Chien, Hsiung-Fei; Kao, Chiu-Hua; Huang, Ching-Jang; Chen, Yuh-Lien

    2010-09-01

    Sesame lignans have antioxidative and anti-inflammatory properties. We focused on the effects of the lignans sesamin and sesamol on the expression of endothelial-leukocyte adhesion molecules in tumor necrosis factor-alpha (TNF-alpha)-treated human aortic endothelial cells (HAECs). When HAECs were pretreated with sesamin (10 or 100 microM), the TNF-alpha-induced expression of intercellular cell adhesion molecule-1 (ICAM-1) was significantly reduced (35 or 70% decrease, respectively) by Western blotting. Sesamol was less effective at inhibiting ICAM-1 expression (30% decrease at 100 microM). Sesamin and sesamol reduced the marked TNF-alpha-induced increase in human antigen R (HuR) translocation and the interaction between HuR and the 3'UTR of ICAM-1 mRNA. Both significantly reduced the binding of monocytes to TNF-alpha-stimulated HAECs. Sesamin significantly attenuated TNF-alpha-induced ICAM-1 expression and cell adhesion by downregulation of extracellular signal-regulated kinase 1/2 and p38. Furthermore, in vivo, sesamin attenuated intimal thickening and ICAM-1 expression seen in aortas of apolipoprotein-E-deficient mice. Taken together, these data suggest that sesamin inhibits TNF-alpha-induced extracellular signal-regulated kinase/p38 phosphorylation, nuclear translocation of NF-kappaB p65, cytoplasmic translocalization of HuR and thereby suppresses ICAM-1 expression, resulting in reduced adhesion of leukocytes. These results also suggest that sesamin may prevent the development of atherosclerosis and inflammatory responses.

  4. Zebrafish as a model for apolipoprotein biology: comprehensive expression analysis and a role for ApoA-IV in regulating food intake

    PubMed Central

    Otis, Jessica P.; Zeituni, Erin M.; Thierer, James H.; Anderson, Jennifer L.; Brown, Alexandria C.; Boehm, Erica D.; Cerchione, Derek M.; Ceasrine, Alexis M.; Avraham-Davidi, Inbal; Tempelhof, Hanoch; Yaniv, Karina; Farber, Steven A.

    2015-01-01

    Improved understanding of lipoproteins, particles that transport lipids throughout the circulation, is vital to developing new treatments for the dyslipidemias associated with metabolic syndrome. Apolipoproteins are a key component of lipoproteins. Apolipoproteins are proteins that structure lipoproteins and regulate lipid metabolism through control of cellular lipid exchange. Constraints of cell culture and mouse models mean that there is a need for a complementary model that can replicate the complex in vivo milieu that regulates apolipoprotein and lipoprotein biology. Here, we further establish the utility of the genetically tractable and optically clear larval zebrafish as a model of apolipoprotein biology. Gene ancestry analyses were implemented to determine the closest human orthologs of the zebrafish apolipoprotein A-I (apoA-I), apoB, apoE and apoA-IV genes and therefore ensure that they have been correctly named. Their expression patterns throughout development were also analyzed, by whole-mount mRNA in situ hybridization (ISH). The ISH results emphasized the importance of apolipoproteins in transporting yolk and dietary lipids: mRNA expression of all apolipoproteins was observed in the yolk syncytial layer, and intestinal and liver expression was observed from 4–6 days post-fertilization (dpf). Furthermore, real-time PCR confirmed that transcription of three of the four zebrafish apoA-IV genes was increased 4 hours after the onset of a 1-hour high-fat feed. Therefore, we tested the hypothesis that zebrafish ApoA-IV performs a conserved role to that in rat in the regulation of food intake by transiently overexpressing ApoA-IVb.1 in transgenic larvae and quantifying ingestion of co-fed fluorescently labeled fatty acid during a high-fat meal as an indicator of food intake. Indeed, ApoA-IVb.1 overexpression decreased food intake by approximately one-third. This study comprehensively describes the expression and function of eleven zebrafish apolipoproteins

  5. Cross-species pharmacokinetic comparison from mouse to man of a second-generation antisense oligonucleotide, ISIS 301012, targeting human apolipoprotein B-100.

    PubMed

    Yu, Rosie Z; Kim, Tae-Won; Hong, An; Watanabe, Tanya A; Gaus, Hans J; Geary, Richard S

    2007-03-01

    The pharmacokinetics of a 2'-O-(2-methoxyethyl)-modified oligonucleotide, ISIS 301012 [targeting human apolipoprotein B-100 (apoB-100)], was characterized in mouse, rat, monkey, and human. Plasma pharmacokinetics following parental administration was similar across species, exhibiting a rapid distribution phase with t(1/2alpha) of several hours and a prolonged elimination phase with t(1/2beta) of days. The prolonged elimination phase represents equilibrium between tissues and circulating drug due to slow elimination from tissues. Absorption was nearly complete following s.c. injection, with bioavailability ranging from 80 to 100% in monkeys. Plasma clearance scaled well across species as a function of body weight alone, and this correlation was improved when corrected for plasma protein binding. In all of the animal models studied, the highest tissue concentrations of ISIS 301012 were observed in kidney and liver. Urinary excretion was less than 3% in monkeys and human in the first 24 h. ISIS 301012 is highly bound to plasma proteins, probably preventing rapid removal by renal filtration. However, following 25 mg/kg s.c. administration in mouse and 5-mg/kg i.v. bolus administration in rat, plasma concentrations of ISIS 301012 exceeded their respective protein binding capacity. Thus, urinary excretion increased to 16% or greater within the first 24 h. Albeit slow, urinary excretion of ISIS 301012 and its shortened metabolites is the ultimate elimination pathway of this compound, as demonstrated by 32% of dose recovered in total excreta by 14 days in a rat mass balance study. The pharmacokinetics of ISIS 301012 in human is predictable from the pharmacokinetics measured in animals. The pharmacokinetic properties of ISIS 301012 provide guidance for clinical development and support infrequent dose administration.

  6. Independent effects of apolipoprotein AV and apolipoprotein CIII on plasma triglyceride concentrations

    SciTech Connect

    Baroukh, Nadine N.; Bauge, Eric; Akiyama, Jennifer; Chang, Jessie; Fruchart, Jean-Charles; Rubin, Edward M.; Fruchart, Jamila; Pennacchio, Len A.

    2003-08-15

    Both the apolipoprotein A5 and C3 genes have repeatedly been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. In mice, transgenic and knockout experiments indicate that plasma triglyceride levels are negatively and positively correlated with APOA5 and APOC3 expression, respectively. In humans, common polymorphisms in both genes have also been associated with plasma triglyceride concentrations. The evolutionary relationship among these two apolipoprotein genes and their close proximity on human chromosome 11q23 have largely precluded the determination of their relative contribution to altered Both the apolipoprotein A5 and C3 genes have repeatedly been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. In mice, transgenic and knockout experiments indicate that plasma triglyceride levels are negatively and positively correlated with APOA5 and APOC3 expression, respectively. In humans, common polymorphisms in both genes have also been associated with plasma triglyceride concentrations. The evolutionary relationship among these two apolipoprotein genes and their close proximity on human chromosome 11q23 have largely precluded the determination of their relative contribution to altered triglycerides. To overcome these confounding factors and address their relationship, we generated independent lines of mice that either over-expressed (''double transgenic'') or completely lacked (''double knockout'') both apolipoprotein genes. We report that both ''double transgenic'' and ''double knockout'' mice display intermedia tetriglyceride concentrations compared to over-expression or deletion of either gene alone. Furthermore, we find that human ApoAV plasma protein levels in the ''double transgenic'' mice are approximately 500-fold lower than human ApoCIII levels, supporting ApoAV is a potent triglyceride modulator despite its low concentration. Together, these data indicate

  7. Phenotypes of apolipoprotein B and apolipoprotein E after liver transplantation.

    PubMed Central

    Linton, M F; Gish, R; Hubl, S T; Bütler, E; Esquivel, C; Bry, W I; Boyles, J K; Wardell, M R; Young, S G

    1991-01-01

    Apolipoprotein (apo) E and the two B apolipoproteins, apoB48 and apoB100, are important proteins in human lipoprotein metabolism. Commonly occurring polymorphisms in the genes for apoE and apoB result in amino acid substitutions that produce readily detectable phenotypic differences in these proteins. We studied changes in apoE and apoB phenotypes before and after liver transplantation to gain new insights into apolipoprotein physiology. In all 29 patients that we studied, the postoperative serum apoE phenotype of the recipient, as assessed by isoelectric focusing, converted virtually completely to that of the donor, providing evidence that greater than 90% of the apoE in the plasma is synthesized by the liver. In contrast, the cerebrospinal fluid apoE phenotype did not change to the donor's phenotype after liver transplantation, indicating that most of the apoE in CSF cannot be derived from the plasma pool and therefore must be synthesized locally. The apoB100 phenotype (assessed with immunoassays using monoclonal antibody MB19, an antibody that detects a two-allele polymorphism in apoB) invariably converted to the phenotype of the donor. In four normolipidemic patients, we determined the MB19 phenotype of both the apoB100 and apoB48 in the "chylomicron fraction" isolated from plasma 3 h after a fat-rich meal. Interestingly, the apoB100 in the chylomicron fraction invariably had the phenotype of the donor, indicating that the vast majority of the large, triglyceride-rich apoB100-containing lipoproteins that appear in the plasma after a fat-rich meal are actually VLDL of hepatic origin. The MB19 phenotype of the apoB48 in the plasma chylomicron fraction did not change after liver transplantation, indicating that almost all of the apoB48 in plasma chylomicrons is derived from the intestine. These results were consistent with our immunocytochemical studies on intestinal biopsy specimens of organ donors; using apoB-specific monoclonal antibodies, we found evidence for

  8. Artificial Intelligence Study (AIS).

    DTIC Science & Technology

    1987-02-01

    ARTIFICIAL INTELLIGNECE HARDWARE ....... 2-50 AI Architecture ................................... 2-49 AI Hardware ....................................... 2...Epstein (1986) has suggested that this version of PROLOG has been used for business and industrial applications in Eastern Europe. The Japanese have...have been in building expert systems in the business analysis area. Expert systems for policy and rate selection for insurance (i.e., risk analysis) and

  9. Comparison of Serum Apolipoproteins and Traditional Lipids in Eyes with Diabetic Retinopathy in Indian Population: A Case Series

    PubMed Central

    Prakash, Gunjan; Agrawal, Rachit; Satsangi, S. K.; Prakash, Shikha

    2016-01-01

    Purpose: To review the associations of serum lipoproteins and apolipoproteins with diabetic retinopathy (DR). Materials and Methods: This was a cross-sectional study of patients of DR. DR was graded according to modified Airlie House Classification system. Traditional serum lipids (total, low-density lipoprotein [LDL], and high-density lipoprotein [HDL] cholesterol and triglycerides [TGs]), apolipoprotein AI (apoAI), apolipoprotein B (apoB), and apoB-to-apoAI ratios were assessed. The analysis of variance test was applied. P < 0.05 was considered statistically significant, and P < 0.001 was considered highly significant. Results: Twenty-four patients with DR were evaluated. Serum apoAI was statistically significantly associated with a reduced likelihood of having more severe DR levels (P < 0.001). Increasing levels of apoB (P < 0.001) and apoB-to-apoAI ratio (P < 0.001) were statistically significantly associated with increasing DR severity levels. The association of total (P > 0.05) and LDL cholesterol (P > 0.05) with severity of DR was not statistically significant. HDL cholesterol levels were inversely associated with the severity of DR (P < 0.05). TGs were also statistically significantly associated with the severity of DR (P < 0.05). Conclusion: Serum apolipoprotein levels may be stronger biomarkers of DR than traditional lipids. PMID:27162455

  10. Black knight of AI

    SciTech Connect

    Rose, F.

    1985-03-01

    For two decades now, Hubert Dreyfus, an existentialist philosopher at the University of California at Berkeley, has been in the forefront of the controversy over artificial intelligence. He maintains that computers will never be able to think because scientists will never come up with a suitably rigorous set of rules to describe how we think. To many computer scientists, this is like saying the Earth is flat. But so far, none of them have been able to prove him wrong. Even most AI researchers now admit that before they can make computers any smarter, they'll have to come up with an explanation of how intelligence works in people. This realization has coincided with the emergence of cognitive science, a new discipline linking philosophy, psychology, anthroplogy, linguistics, neuroscience, and computer science in an attempt to develop a theory of the way humans think. The guiding principle of most cognitive science research is the notion that the mind, like the computer, is a system for manipulating symbols - for processing information. The task of cognitive science is to discover how this processing occurs.

  11. T'ai Chi

    MedlinePlus

    ... you start your first t'ai chi workout, dress comfortably so you can move and stretch easily. ... health problem. Is your schedule jam-packed with school, work, and social activities? Here are a few ...

  12. T'ai Chi

    MedlinePlus

    ... chi (pronounced: TY CHEE) is great for improving flexibility and strengthening your legs, abs, and arms. What ... general, though, practicing t'ai chi improves strength, flexibility, and respiratory function (breathing). So where can you ...

  13. AI aerospace components

    NASA Technical Reports Server (NTRS)

    Heindel, Troy A.; Murphy, Terri B.; Rasmussen, Arthur N.; Mcfarland, Robert Z.; Montgomery, Ronnie E.; Pohle, George E.; Heard, Astrid E.; Atkinson, David J.; Wedlake, William E.; Anderson, John M.

    1991-01-01

    An evaluation is made of the application of novel, AI-capabilities-related technologies to aerospace systems. Attention is given to expert-system shells for Space Shuttle Orbiter mission control, manpower and processing cost reductions at the NASA Kennedy Space Center's 'firing rooms' for liftoff monitoring, the automation of planetary exploration systems such as semiautonomous mobile robots, and AI for battlefield staff-related functions.

  14. An immunohistochemical study of human platelets using a rabbit antibody against H18-K24 of apolipoprotein CIII (HATKTAK).

    PubMed

    Yamanaka, Takao; Sakamoto, Haruhiko; Nakagawa, Toshitaka; Tanaka, Sumiko; Matsumoto, Kouichi; Ueno, Masaki

    2013-08-01

    H18-K24 of human apolipopotein CIII (Apo CIII) (HATKTAK) is an activator of the macromolecular activators of phagocytosis from platelets (MAPPs). Using a rabbit antibody against HATKTAK, we performed an immunohistochemical study of human platelets. Indirect ELISA showed that this antibody reacts with Apo CIII-derived peptides with a C-terminal of HATKTAK, but not with Apo CIII. Immunoelectron microscopy revealed that reaction of anti-HATKTAK antibody occurred in the pseudopods of activated platelets. In blood coagula produced from the peripheral blood and formalin-fixed after various incubation periods, reaction of this antibody with platelets appeared rapidly with a peak at 3 to 6 h of incubation, and then diminished gradually. Leukocytes in the blood coagula were stained strongly positive. In tissue sections, fresh thrombi and hemorrhages with slight fibrin formation revealed a positive response of platelets to anti-HATKTAK antibody, whereas older ones with leukocytic infiltration, fibrin formation and organization did not. In addition to platelets, endothelial cells and leukocytes were stained positive by anti-HATKTAK antibody. All of the positive reactions by anti-HATKTAK antibody disappeared or diminished by co-incubation with HATKTAK. In conclusion, the anti-HATKTAK antibody reveals platelets during the early phase of activation.

  15. Cerebral Apolipoprotein-D Is Hypoglycosylated Compared to Peripheral Tissues and Is Variably Expressed in Mouse and Human Brain Regions

    PubMed Central

    Li, Hongyun; Ruberu, Kalani; Karl, Tim; Garner, Brett

    2016-01-01

    Recent studies have shown that cerebral apoD levels increase with age and in Alzheimer’s disease (AD). In addition, loss of cerebral apoD in the mouse increases sensitivity to lipid peroxidation and accelerates AD pathology. Very little data are available, however, regarding the expression of apoD protein levels in different brain regions. This is important as both brain lipid peroxidation and neurodegeneration occur in a region-specific manner. Here we addressed this using western blotting of seven different regions (olfactory bulb, hippocampus, frontal cortex, striatum, cerebellum, thalamus and brain stem) of the mouse brain. Our data indicate that compared to most brain regions, the hippocampus is deficient in apoD. In comparison to other major organs and tissues (liver, spleen, kidney, adrenal gland, heart and skeletal muscle), brain apoD was approximately 10-fold higher (corrected for total protein levels). Our analysis also revealed that brain apoD was present at a lower apparent molecular weight than tissue and plasma apoD. Utilising peptide N-glycosidase-F and neuraminidase to remove N-glycans and sialic acids, respectively, we found that N-glycan composition (but not sialylation alone) were responsible for this reduction in molecular weight. We extended the studies to an analysis of human brain regions (hippocampus, frontal cortex, temporal cortex and cerebellum) where we found that the hippocampus had the lowest levels of apoD. We also confirmed that human brain apoD was present at a lower molecular weight than in plasma. In conclusion, we demonstrate apoD protein levels are variable across different brain regions, that apoD levels are much higher in the brain compared to other tissues and organs, and that cerebral apoD has a lower molecular weight than peripheral apoD; a phenomenon that is due to the N-glycan content of the protein. PMID:26829325

  16. Electrophoretic analysis of oxidative modification of apolipoprotein E in very low density lipoprotein from fresh human plasma.

    PubMed

    Kashiwagi, S; Nakamura, K; Arai, H; Yamashita, H; Ito, H

    1999-06-01

    Ferrous ion-induced oxidative modification of apoE in lipid peroxidation of human very low density lipoprotein (VLDL) and the role of the cysteinyl group, present in apoE3 but absent in apoE4, were examined. Fresh human VLDL was obtained from healthy volunteers with different apoE phenotypes as determined by isoelectric focusing (IEF). The VLDL was oxidized by incubating with FeSO4. The time course of the lipid peroxidation was determined by thiobarbituric acid (TBA) assay. The sequential oxidative modification of the apoE was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting with an anti-apoE antibody. To modify the cysteinyl group of apoE3, the VLDL from the apoE3/3 subject was pretreated with cysteamine before the TBA assay and electrophoresis. The ferrous ion-induced peroxidation of the VLDL was pH-dependent, with increased reactivity at acidic pH ranges. In the initial stage of the lipid peroxidation of the VLDL, aggregates were formed involving apoE dimers and apoB via disulfide bonds, followed by the intra- and intermolecular cross-linkings of apoE monomers. The VLDL with apoE3/4 showed a shorter lag time than the VLDL with apoE3/3 in the TBA assay, suggesting a lower antioxidative effect with apoE3/4. The apoE3/3 pretreated with cysteamine showed the patterns of apoE3/4 in IEF and SDS-PAGE with immunoblotting, but it did not show the shortened lag time in the TBA assay. This suggests that factors other than cysteinyl groups contribute to the reduced antioxidative activity of apoE4.

  17. Artificial intelligence. Fears of an AI pioneer.

    PubMed

    Russell, Stuart; Bohannon, John

    2015-07-17

    From the enraged robots in the 1920 play R.U.R. to the homicidal computer H.A.L. in 2001: A Space Odyssey, science fiction writers have embraced the dark side of artificial intelligence (AI) ever since the concept entered our collective imagination. Sluggish progress in AI research, especially during the “AI winter” of the 1970s and 1980s, made such worries seem far-fetched. But recent breakthroughs in machine learning and vast improvements in computational power have brought a flood of research funding— and fresh concerns about where AI may lead us. One researcher now speaking up is Stuart Russell, a computer scientist at the University of California, Berkeley, who with Peter Norvig, director of research at Google, wrote the premier AI textbook, Artificial Intelligence: A Modern Approach, now in its third edition. Last year, Russell joined the Centre for the Study of Existential Risk at Cambridge University in the United Kingdom as an AI expert focusing on “risks that could lead to human extinction.” Among his chief concerns, which he aired at an April meeting in Geneva, Switzerland, run by the United Nations, is the danger of putting military drones and weaponry under the full control of AI systems. This interview has been edited for clarity and brevity.

  18. Silver-enhanced radial immunodiffusion assay of plasma apolipoproteins.

    PubMed

    Ishida, B Y; Paigen, B

    1992-07-01

    Silver-staining of immunoprecipitates extends the sensitivity of the radial immunodiffusion assay by tenfold. This modification permits the quantification of apolipoproteins A-I, A-II, C, and E at levels of 0.2-1.0 mg/dl in plasma samples at a sensitivity threshold of 10 ng. The silver-enhanced radial immunodiffusion method is readily adapted from the standard method, simple and inexpensive to perform, and does not require costly instrumentation. These advantages make the modified RID assay an attractive alternative to other forms of immunoassay.

  19. The Structure of Human Apolipoprotein A-IV as Revealed by Stable Isotope-assisted Cross-linking, Molecular Dynamics, and Small Angle X-ray Scattering*

    PubMed Central

    Walker, Ryan G.; Deng, Xiaodi; Melchior, John T.; Morris, Jamie; Tso, Patrick; Jones, Martin K.; Segrest, Jere P.; Thompson, Thomas B.; Davidson, W. Sean

    2014-01-01

    Apolipoprotein (apo)A-IV plays important roles in dietary lipid and glucose metabolism, and knowledge of its structure is required to fully understand the molecular basis of these functions. However, typical of the entire class of exchangeable apolipoproteins, its dynamic nature and affinity for lipid has posed challenges to traditional high resolution structural approaches. We previously reported an x-ray crystal structure of a dimeric truncation mutant of apoA-IV, which showed a unique helix-swapping molecular interface. Unfortunately, the structures of the N and C termini that are important for lipid binding were not visualized. To build a more complete model, we used chemical cross-linking to derive distance constraints across the full-length protein. The approach was enhanced with stable isotope labeling to overcome ambiguities in determining molecular span of the cross-links given the remarkable similarities in the monomeric and dimeric apoA-IV structures. Using 51 distance constraints, we created a starting model for full-length monomeric apoA-IV and then subjected it to two modeling approaches: (i) molecular dynamics simulations and (ii) fitting to small angle x-ray scattering data. This resulted in the most detailed models yet for lipid-free monomeric or dimeric apoA-IV. Importantly, these models were of sufficient detail to direct the experimental identification of new functional residues that participate in a “clasp” mechanism to modulate apoA-IV lipid affinity. The isotope-assisted cross-linking approach should prove useful for further study of this family of apolipoproteins in both the lipid-free and -bound states. PMID:24425874

  20. Familial apolipoprotein E deficiency.

    PubMed Central

    Schaefer, E J; Gregg, R E; Ghiselli, G; Forte, T M; Ordovas, J M; Zech, L A; Brewer, H B

    1986-01-01

    A unique kindred with premature cardiovascular disease, tubo-eruptive xanthomas, and type III hyperlipoproteinemia (HLP) associated with familial apolipoprotein (apo) E deficiency was examined. Homozygotes (n = 4) had marked increases in cholesterol-rich very low density lipoproteins (VLDL) and intermediate density lipoproteins (IDL), which could be effectively lowered with diet and medication (niacin, clofibrate). Homozygotes had only trace amounts of plasma apoE, and accumulations of apoB-48 and apoA-IV in VLDL, IDL, and low density lipoproteins. Radioiodinated VLDL apoB and apoE kinetic studies revealed that the homozygous proband had markedly retarded fractional catabolism of VLDL apoB-100, apoB-48 and plasma apoE, as well as an extremely low apoE synthesis rate as compared to normals. Obligate heterozygotes (n = 10) generally had normal plasma lipids and mean plasma apoE concentrations that were 42% of normal. The data indicate that homozygous familial apoE deficiency is a cause of type III HLP, is associated with markedly decreased apoE production, and that apoE is essential for the normal catabolism of triglyceride-rich lipoprotein constituents. Images PMID:3771793

  1. AI in manufacturing

    NASA Technical Reports Server (NTRS)

    Gross, John E.; Minato, Rick; Smith, David M.; Loftin, R. B.; Savely, Robert T.

    1991-01-01

    AI techniques are shown to have been useful in such aerospace industry tasks as vehicle configuration layouts, process planning, tool design, numerically-controlled programming of tools, production scheduling, and equipment testing and diagnosis. Accounts are given of illustrative experiences at the production facilities of three major aerospace defense contractors. Also discussed is NASA's autonomous Intelligent Computer-Aided Training System, for such ambitious manned programs as Space Station Freedom, which employs five different modules to constitute its job-independent training architecture.

  2. Effect of intestinal chylomicron secretory blockade on apolipoprotein synthesis in the newborn piglet.

    PubMed

    Black, D D

    1992-04-01

    Pluronic L-81 is a hydrophobic surfactant which blocks intestinal chylomicron secretion at the pre-Golgi level without affecting triacylglycerol uptake and re-esterification. To study the effects of such blockade on apolipoprotein synthesis, newborn female piglets received 24 h intraduodenal infusions of low-triacylglycerol, or high-triacylglycerol with or without Pluronic L-81, diets, followed by determination of apolipoprotein (apo) B-48, A-I and A-IV synthesis and content and apo B and A-IV mRNA levels in the small intestine. Jejunal apo B-48 content, synthesis and mRNA levels were down-regulated below basal levels by the addition of Pluronic to the high-triacylglycerol infusion. The normal increase in apo A-I synthesis induced by triacylglycerol absorption was ablated in both jejunum and ileum, even though the expected increase in apo A-I content in jejunum still occurred. Although attenuated, the expected increase in jejunal apo A-IV synthesis and mRNA levels with triacylglycerol absorption was still present with Pluronic treatment. These results suggest very different mechanisms of cellular regulation and trafficking for the various apolipoproteins incorporated into nascent intestinal chylomicrons. Apo B may be specifically down-regulated by the chylomicron secretory blockade induced by Pluronic L-81.

  3. Increased production of apolipoprotein B and its lipoproteins by oleic acid in Caco-2 cells.

    PubMed

    Dashti, N; Smith, E A; Alaupovic, P

    1990-01-01

    The production of lipids, apolipoproteins (apo), and lipoproteins induced by oleic acid has been examined in Caco-2 cells. The rates of accumulation in the control medium of 15-day-old Caco-2 cells of triglycerides, unesterified cholesterol, and cholesteryl esters were 102 +/- 8, 73 +/- 5, and 11 +/- 1 ng/mg cell protein/h, respectively; the accumulation rates for apolipoproteins A-I, B, C-III, and E were 111 +/- 9, 53 +/- 4, 13 +/- 1, and 63 +/- 4 ng/mg cell protein/h, respectively. Whereas apolipoproteins A-IV and C-II were detected by immunoblotting, apoA-II was absent in most culture media. In contrast to an early production of apolipoproteins A-I and E occurring 2 days after plating, the apoB expression appeared to be differentiation-dependent and was not measurable in the medium until the sixth day post-confluency. In the control medium, very low density lipoproteins (VLDL), low density lipoproteins (LDL), high density lipoproteins (HDL), and lipid-poor very high density lipoproteins (VHDL) accounted for 12%, 46%, 18%, and 24% of the total lipid and apolipoprotein contents, respectively. The triglyceride-rich VLDL contained mainly apoE (75%) and apoB (23%), while the protein moiety of LDL was composed of apoB (59%), apoE (20%), apoA-I (15%), and apoC-III (6%). The cholesterol-rich HDL contained mainly apoA-I (69%) and apoE (27%). In the control medium, major portions of apolipoproteins B and C-III (93-97%) were present in LDL, whereas the main parts of apoA-I (92%) and apoE (76%) were associated with HDL and VHDL. Oleate increased the production of triglycerides 10-fold, cholesteryl esters 7-fold, and apoB 2- to 4-fold. There was also a moderate increase (39%) in the production of apoC-III but no significant changes in those of apolipoproteins A-I and E. These increases were reflected mainly in a 55-fold elevation in the concentration of VLDL, and a 2-fold increase in the level of LDL; there were no significant changes in HDL and VHDL. VLDL contained the

  4. Pro-apoptotic activities of polyphenolics from açai (Euterpe oleracea Martius) in human SW-480 colon cancer cells.

    PubMed

    Dias, Manoela Maciel dos Santos; Noratto, Giuliana; Martino, Hercia Stampini Duarte; Arbizu, Shirley; Peluzio, Maria do Carmo Gouveia; Talcott, Stephen; Ramos, Afonso Mota; Mertens-Talcott, Susanne U

    2014-01-01

    This study aimed to evaluate the cell growth inhibition activity of açai (Euterpe oleracea Mart.) polyphenolic extract against colon cancer HT-29 and SW-480 cells and the nonmalignant CCD-18Co colon fibroblast cells. Results showed that açai polyphenolic extract (5-20 mg/L) inhibited preferentially the growth of SW-480 cells with no toxicity in CCD-18Co cells, and this was accompanied by reduction of H2O2-induced reactive oxygen species (ROS) generation. The mechanisms involved in SW-480 cell growth-inhibition by açai polyphenolic extract included the downregulation of NF-κB proinflammatory transcription factor and the nuclear factor-kappa B targets intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Furthermore, prooncogenic specificity proteins (Sp) were downregulated as well as Sp-targets Bcl-2, vascular endothelial growth factor, and survivin. This was accompanied by activation of mitochondrial proapoptotic pathway involving increase of cytochrome c, cleavage of caspase-3, and decrease of PARP-1. Results strongly suggest that açai polyphenolic extract has antiinflammatory and cytotoxic activities in colon cancer cells and can be effective as natural colon cancer chemopreventive agents.

  5. Apolipoprotein E genotype in schizophrenia

    SciTech Connect

    Joober, R.; Lal, S.; Bloom, D.; Benkelfat, C.

    1996-04-09

    We investigated the association between schizophrenia and the allelic polymorphism in the apolipoprotein E (Apo E) gene in 51 schizophrenic patients and 35 controls. The Apo E4 allele was equally represented in the schizophrenic group (16%) and the control group (20%) suggesting no association between schizophrenia and the Apo E4 allele. The apolipoprotein E (Apo E) is a polymorphic (E2, E3, and E4) lipoprotein involved in the transmembrane transport of cholesterol and is thought to play an important role in neuronal growth and in the central nervous system response to injury, particularly in the hippocampal region. Recent findings strongly suggest that the Apo E4 allele is associated with cognitive deficits in normal and pathological aging, e.g., Alzheimer`s disease. 5 refs., 1 tab.

  6. Overexpression of apolipoprotein AII in transgenic mice converts high density lipoproteins to proinflammatory particles.

    PubMed Central

    Castellani, L W; Navab, M; Van Lenten, B J; Hedrick, C C; Hama, S Y; Goto, A M; Fogelman, A M; Lusis, A J

    1997-01-01

    Previous studies showed that transgenic mice overexpressing either apolipoprotein AI (apoAI) or apolipoprotein AII (apoAII), the major proteins of HDL, exhibited elevated levels of HDL cholesterol, but, whereas the apoAI-transgenic mice were protected against atherosclerosis, the apoAII-transgenic mice had increased lesion development. We now examine the basis for this striking functional heterogeneity. HDL from apoAI transgenics exhibited an enhanced ability to promote cholesterol efflux from macrophages, but HDL from apoAII transgenics and nontransgenics were not discernibly different in efflux studies. In contrast with HDL from nontransgenics and apoAI transgenics, HDL from the apoAII transgenics were unable to protect against LDL oxidation in a coculture model of the artery wall. Furthermore, HDL taken from apoAII-transgenic mice, but not HDL taken from either the apoAI transgenics or nontransgenic littermate controls, by itself stimulated lipid hydroperoxide formation in artery wall cells and induced monocyte transmigration, indicating that the apoAII-transgenic HDL were in fact proinflammatory. This loss in the ability of the apoAII-transgenic HDL to function as an antioxidant/antiinflammatory agent was associated with a decreased content of paraoxonase, an enzyme that protects against LDL oxidation. Reconstitution of the apoAII transgenic HDL with purified paraoxonase restored both paraoxonase activity and the ability to protect against LDL oxidation. We conclude that overexpression of apoAII converts HDL from an anti- to a proinflammatory particle and that paraoxonase plays a role in this transformation. PMID:9218525

  7. Apolipoprotein A1 as a novel anti-implantation biomarker in polycystic ovary syndrome: A case-control study

    PubMed Central

    Amjadi, Fatemehsadat; Aflatoonian, Reza; Javanmard, Shaghayegh Haghjoo; Saifi, Bita; Ashrafi, Mahnaz; Mehdizadeh, Mehdi

    2015-01-01

    Background: Women with polycystic ovary syndrome have lower pregnancy rates, possibly due to the decreased uterine receptivity. Successful implantation depends on protein networks that are essential for cross-talk between the embryo and endometrium. Apolipoprotein A1 has been proposed as a putative anti-implantation factor. In this study, we evaluated apolipoprotein A1 expression in human endometrial tissues. Materials and Methods: Endometrial apolipoprotein A1 messenger RNA (mRNA) and protein expression were investigated using quantitative real-time polymerase chain reaction (PCR) and Western blot. The distribution of apolipoprotein A1 was also detected by immunostaining. Samples were obtained from 10 patients with polycystic ovary syndrome and 15 healthy fertile women in the proliferative (on day 2 or day 3 before ovulation, n = 7) and secretory (on days 3-5 after ovulation, n = 8) phases. Results: Endometrial apolipoprotein A1 expression was upregulated in patients with polycystic ovary syndrome compared to normal subjects. However, apolipoprotein A1 expression in the proliferative phase was significantly higher than in the luteal phase (P value < 0.05). Conclusion: It seems that differentially expressed apolipoprotein A1 negatively affects endometrial receptivity in patients with polycystic ovary syndrome. The results showed that apolipoprotein A1 level significantly changes in the human endometrium during the menstrual cycle with minimum expression in the secretory phase, coincident with the receptive phase (window of implantation). Further studies are required to clarify the clinical application of this protein. PMID:26941806

  8. Human ABCA1 BAC transgenic mice show increased high density lipoprotein cholesterol and ApoAI-dependent efflux stimulated by an internal promoter containing liver X receptor response elements in intron 1.

    PubMed

    Singaraja, R R; Bocher, V; James, E R; Clee, S M; Zhang, L H; Leavitt, B R; Tan, B; Brooks-Wilson, A; Kwok, A; Bissada, N; Yang, Y Z; Liu, G; Tafuri, S R; Fievet, C; Wellington, C L; Staels, B; Hayden, M R

    2001-09-07

    By using BAC transgenic mice, we have shown that increased human ABCA1 protein expression results in a significant increase in cholesterol efflux in different tissues and marked elevation in high density lipoprotein (HDL)-cholesterol levels associated with increases in apoAI and apoAII. Three novel ABCA1 transcripts containing three different transcription initiation sites that utilize sequences in intron 1 have been identified. In BAC transgenic mice there is an increased expression of ABCA1 protein, but the distribution of the ABCA1 product in different cells remains similar to wild type mice. An internal promoter in human intron 1 containing liver X response elements is functional in vivo and directly contributes to regulation of the human ABCA1 gene in multiple tissues and to raised HDL cholesterol, apoAI, and apoAII levels. A highly significant relationship between raised protein levels, increased efflux, and level of HDL elevation is evident. These data provide proof of the principle that increased human ABCA1 efflux activity is associated with an increase in HDL levels in vivo.

  9. Intestinal apolipoprotein synthesis and secretion in the suckling pig.

    PubMed

    Black, D D; Davidson, N O

    1989-02-01

    The present studies report characterization of intestinal apolipoprotein (apoLp) synthesis and secretion in the suckling pig. Lipoproteins (d less than 1.006 g/ml) from mesenteric lymph were found to contain both apoB-100 and B-48, in addition to apoA-IV, E, A-I, and Cs. Lymph low density lipoproteins (LDL) and high density lipoproteins (HDL) contained mainly apoB-100 and apoA-I, respectively. Analysis of core cholesteryl ester fatty acid composition suggested filtration from plasma as the major source of lymph LDL and HDL. Dual radioisotope labeling of intestinal and hepatic apoLps in lymph, as well as immunoprecipitation of radiolabeled intestinal mucosa, demonstrated intestinal synthesis of apoB-48, A-IV, and A-I. There was no evidence for apoB-100 synthesis by intestinal mucosa. By contrast, piglet liver synthesized apoB-100, E, A-I, and Cs, but not apoB-48. Newly synthesized intracellular intestinal apoA-I was mainly (basic) isoform 1 (pI 5.58), while lymph and plasma HDL apoA-I were predominantly isoform 3 (pI 5.33), mature apoA-I. Lymph apoB (P less than 0.001) and apoA-I (P less than 0.04) mass output increased significantly during lipid absorption. Studies were subsequently conducted in fasting, fat-fed, bile-diverted, and sham-operated animals to determine the role of both dietary and biliary lipid in regulating intestinal apoLp biosynthesis. Proximal and distal small intestinal loops were pulse-radiolabeled with [3H]leucine, and apoB-48 and A-I were immunoprecipitated from cytosolic supernatants. Although a proximal to distal gradient in intestinal synthesis rates for both apoB and A-I was noted in all groups, the acute absorption of dietary lipid did not significantly increase apoB or A-I synthesis in either location. Complete removal of biliary lipid for 48 hr did not alter synthesis rates in jejunum or ileum. These studies suggest that mesenteric lymph apoLps in the suckling pig are derived both by filtration from plasma and by direct secretion from

  10. Multivitamin supplementation of adult omnivores and lactovegetarians: circulating levels of vitamin A, D and E, lipids, apolipoproteins and selenium.

    PubMed

    Kumpusalo, E; Karinpää, A; Jauhiainen, M; Laitinen, M; Lappeteläinen, R; Mäenpää, P H

    1990-01-01

    Serum levels of fat-soluble vitamins, lipids, apolipoproteins, total protein, hemoglobin, iron, and selenium were determined in healthy Finnish adults during a 7-month period beginning in January and ending in August. The subjects were either omnivores or established lactovegetarians, who had consumed their respective diets for at least 6 months prior to the study. Half of the subjects in both groups received daily multivitamin supplementation and the other half served as controls. In the beginning, the lactovegetarians differed from the omnivores in having lower serum levels of protein, apolipoproteins A-I and C-II, and higher levels of standardized alpha-tocopherol. During the study, serum retinol and standardized alpha-tocopherol (in March and May), as well as apolipoproteins A-I and C-II, and selenium decreased in the omnivores and 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, cholesterol, HDL-cholesterol, and the HDL-cholesterol/cholesterol ratio increased. Apolipoprotein B decreased and then increased. In the lactovegetarians, serum selenium and protein decreased during the study, whereas retinol and alpha-tocopherol stayed higher than in the omnivores. Consumption of the lactovegetarian diet was accompanied by lower circulating levels of cholesterol and selenium and higher levels of retinol and standardized alpha-tocopherol than the mixed diet. Multivitamin supplementation may have value especially for omnivores in northern countries, like Finland, in providing better retinol, alpha-tocopherol, vitamin D, and selenium status in late winter and early spring.

  11. Effect of a high carbohydrate diet on the content of apolipoproteins C-II, C-III and E in human plasma high density lipoprotein subfractions.

    PubMed

    Sasaki, N; Holdsworth, G; Barnhart, R L; Srivastava, L S; Glueck, C J; Kashyap, M L; Jackson, R L

    1983-03-01

    The effect of isocaloric high and low carbohydrate (Carb) diets on the structure and apoprotein composition of plasma high density lipoproteins (HDL) was assessed in four healthy men. The high Carb diet contained 65% calories as Carb and 15% as fat; the low Carb was 15% and 65%, respectively, with protein fixed at 20% of calories in each case. Cholesterol was 400 mg/day and the P/S ratio of the fat was 0.4. Each diet was sequentially consumed for periods of 3 weeks. At the end of each 3-week study period, plasma HDL2 and HDL3 were isolated by zonal ultracentrifugation and their apoprotein and lipid compositions were determined. Compared to the low Carb diet, the high Carb diet was associated with an increase in the size of HDL2 (116.0 +/- 1.8 vs. 109.1 +/- 1.8 A) and in the content (mean weight % +/- SEM) of apoE (2.81 +/- 0.71 vs. 1.79 +/- 0.49, P less than 0.01) and of apoC-II (1.73 +/- 0.09 vs. 1.11 +/- 0.12, P less than 0.01). HDL2 apoC-III content was not significantly different on the two diets (6.49 +/- 0.50 vs. 7.42 +/- 1.21). On the two diets, HDL3 size and HDL3 apoE content were not significantly changed. HDL3 apoC-II and apoC-III, however, were higher on the high Carb diet, P less than 0.05. The ratio (by weight) of HDL2 apoE/HDL2 apoC-II + C-III increased on the high Carb diet compared to the low Carb diet (0.344 +/- 0.058 vs. 0.228 +/- 0.053, P less than 0.01). We suggest that the increased amount of apolipoprotein E in HDL2 may influence its rate of catabolic clearance and may account for the well-known decrease in plasma HDL-cholesterol in subjects on high Carb diets.

  12. Monocytic elastase-mediated apolipoprotein-E degradation: Potential involvement of microglial elastase-like proteases in apolipoprotein-E proteolysis in brains with Alzheimers disease.

    PubMed

    Suenaga, Midori; Furuta, Akiko; Wakabayashi, Koichi; Saibara, Toshiji; Matsunaga, Yoichi

    2015-08-01

    Impaired clearance of soluble Aβ (amyloid-β) promotes Aβ aggregation in brains with Alzheimer's disease (AD), while apolipoprotein-E (ApoE) in microglia mediates Aβ clearance. We studied the protease responsible for ApoE(4) degradation in human peripheral monocyte extracts, which are from the same lineage as microglia. We detected the hydrolytic activity for ApoE(4) in high-salt extracts with 2 M NaCl and found that the activity was inhibited by a serine protease inhibitor and an elastase-specific inhibitor, but not by other protease inhibitors. The extracts exhibited higher activity for the elastase substrate, and we followed the activity with ion-exchange and gel-filtration chromatography. Through silver staining, we partially purified a protein of 28 kDa, which was clarified as elastase by liquid chromatography-tandem mass spectrometry. These observations suggest that elastase is the key protease for ApoE(4) degradation. We also detected ApoE(4) hydrolytic activity in high-salt extracts in mouse microglial (BV-2) cell lysates, and showed that the ApoE(4) fragments by the BV-2 extracts differed from the fragments by the monocyte extracts. Though the ApoE(4) degradation by the extracts was not inhibited with elastase-specific inhibitors, it was inhibited by an elastase-specific monoclonal antibody, suggesting that elastase-like proteases in microglia differ from those of monocytes. Immunohistochemistry revealed that both elastase and ApoE were expressed in the senile plaques of brains with AD. In vitro studies also disclosed the localization of elastase in the microglial cell line, BV-2. Our results suggest that elastase-like proteases in the microglial cells surrounding Aβ plaques are responsible for ApoE degradation in the brain.

  13. Cloning and characterization of a novel apolipoprotein gene, apolipoprotein AV, in tree shrews.

    PubMed

    Li, Guoping; Luo, Huairong; Sun, Guotao; Wu, Guisheng; Wu, Gang; Wang, Yan; Man, Yong; Wang, Shu; Li, Jian; Chen, Baosheng

    2013-09-01

    Apolipoprotein AV (apoAV) modulates plasma triglyceride levels, which is an independent risk factor for cardiovascular disease. ApoAV is also involved in atherosclerosis lesion formation. In order to systematically evaluate the apolipoprotein-related gene profile in tree shrew, a model for its insusceptibility to atherosclerosis, we performed apoAV cloning and characterization. The full-length cDNA of apoAV was identified using SMART-RACE. ApoAV cDNA sequence revealed two transcripts, 1,948 and 1,397 base pairs, due to alternative polyadenylation. These two transcripts share the same open reading frame (ORF), which encodes a 369-amino acid protein with high identity to human apoAV (75 %), including a 23-amino acid N-terminal signal peptide. ApoAV is expressed exclusively in the liver. Mature apoAV was expressed in E. coli BL21(DE3) and purified by Ni-chelated resin. Lipoprotein lipase activity was significantly stimulated by this recombinant protein. The full-length ORF of apoAV was cloned into pDsRed-monomer-N1 vector with a red fluorescent protein tag and was primarily localized in cytoplasm of hepG2 cells. The successful cloning, expression and localization of apoAV in tree shrew has laid down the foundation for further investigation on its structure and functions.

  14. Typical and atypical AIS. Pathogenesis.

    PubMed

    Dudin, M; Pinchuk, D

    2012-01-01

    AIS hypothesis has the right to recognition, if it explains the transition of "healthy" vertebra column into status of "scoliotic" one. AIS is the most investigated disease in the history of orthopedics, but up the present time there is no clear explanation of some its phenomena: vertebra column mono-form deformation along with its poly etiology character, interrelation of its origin and development and child's growth process etc. The key for authors' view at AIS was scoliosis with non-standard (concave side) rotation. On the bases of its' multifunctional instrumental investigation results (Rtg, EMG, EEG, optical topography, hormonal and neuropeptides trials, thermo-vision methods and other) in comparison with typical AIS was worked out the new hypothesis, part of it is suggested for discussion. In the work under observation is the sequence of appearance of typical and atypical scoliosis symptomatology beginning from the preclinical stage.

  15. Code AI Personal Web Pages

    NASA Technical Reports Server (NTRS)

    Garcia, Joseph A.; Smith, Charles A. (Technical Monitor)

    1998-01-01

    The document consists of a publicly available web site (george.arc.nasa.gov) for Joseph A. Garcia's personal web pages in the AI division. Only general information will be posted and no technical material. All the information is unclassified.

  16. AIS ASM Operational Integration Plan

    DTIC Science & Technology

    2013-08-01

    River , WA; and the future Vessel Traffic Service systems being developed under PAWSS. Interfacing the AIS Transmit architecture with agencies that...provides accurate real-time information such as water levels, currents, and other oceanographic and meteorological data. The USACE provide river lock...information and river level and current data on the Inland Waterways. AIS ASM Operational Integration Plan viii UNCLAS//Public | CG-926 R&DC

  17. Cloning of a cDNA encoding a putative human very low density lipoprotein/Apolipoprotein E receptor and assignment of the gene to chromosome 9pter-p23[sup 6

    SciTech Connect

    Gafvels, M.E.; Strauss, J.F. III ); Caird, M.; Patterson, D. ); Britt, D.; Jackson, C.L. )

    1993-11-01

    The authors report the cloning of a 3656-bp cDNA encoding a putative human very low density lipoprotein (VLDL)/apolipoprotein E (ApoE) receptor. The gene encoding this protein was mapped to chromosome 9pter-p23. Northern analysis of human RNA identified cognate mRNAs of 6.0 and 3.8 kb with most abundant expression in heart and skeletal muscle, followed by kidney, placenta, pancreas, and brain. The pattern of expression generally paralleled that of lipoprotein lipase mRNA but differed from that of the low density lipoprotein (LDL) receptor and the low density lipoprotein receptor-related protein/[alpha][sub 2]-macroglobulin receptor (LRP), which are members of the same gene family. VLDL/ApoE receptor message was not detected in liver, whereas mRNAs for both LDL receptor and LRP were found in hepatic tissue. In mouse 3T3-L1 cells, VLDL/ApoE receptor mRNA was induced during the transformation of the cells into adipocytes. Expression was also detected in human choriocarcinoma cells, suggesting that at least part of the expression observed in placenta may be in trophoblasts, cells which would be exposed to maternal blood. Expression in brain may be related to high levels of ApoE expression in that organ, an observation of potential relevance to the recently hypothesized role for ApoE in late onset Alzheimer disease. The results suggest that the putative VLDL/ApoE receptor could play a role in the uptake of triglyceride-rich lipoprotein particles by specific organs including striated and cardiac muscle and adipose tissue and in the transport of maternal lipids across the placenta. The findings presented here, together with recent observations from other laboratories, bring up the possibility that a single gene, the VLDL/ApoE receptor, may play a role in the pathogenesis of certain forms of atherosclerosis, Alzheimer disease, and obesity.

  18. Deploying Embodied AI into Virtual Worlds

    NASA Astrophysics Data System (ADS)

    Burden, David J. H.

    The last two years have seen the start of commercial activity within virtual worlds. Unlike computer games where Non-Player-Character avatars are common, in most virtual worlds they are the exception — and until recently in Second Life they were non-existent. However there is real commercial scope for Als in these worlds — in roles from virtual sales staff and tutors to personal assistants. Deploying an embodied AI into a virtual world offers a unique opportunity to evaluate embodied Als, and to develop them within an environment where human and computer are on almost equal terms. This paper presents an architecture being used for the deployment of chatbot driven avatars within the Second Life virtual world, looks at the challenges of deploying an AI within such a virtual world, the possible implications for the Turing Test, and identifies research directions for the future.

  19. Identification of apolipoprotein using feature selection technique

    PubMed Central

    Tang, Hua; Zou, Ping; Zhang, Chunmei; Chen, Rong; Chen, Wei; Lin, Hao

    2016-01-01

    Apolipoprotein is a kind of protein which can transport the lipids through the lymphatic and circulatory systems. The abnormal expression level of apolipoprotein always causes angiocardiopathy. Thus, correct recognition of apolipoprotein from proteomic data is very crucial to the comprehension of cardiovascular system and drug design. This study is to develop a computational model to predict apolipoproteins. In the model, the apolipoproteins and non-apolipoproteins were collected to form benchmark dataset. On the basis of the dataset, we extracted the g-gap dipeptide composition information from residue sequences to formulate protein samples. To exclude redundant information or noise, the analysis of various (ANOVA)-based feature selection technique was proposed to find out the best feature subset. The support vector machine (SVM) was selected as discrimination algorithm. Results show that 96.2% of sensitivity and 99.3% of specificity were achieved in five-fold cross-validation. These findings open new perspectives to improve apolipoproteins prediction by considering the specific dipeptides. We expect that these findings will help to improve drug development in anti-angiocardiopathy disease. PMID:27443605

  20. D25V apolipoprotein C-III variant causes dominant hereditary systemic amyloidosis and confers cardiovascular protective lipoprotein profile

    PubMed Central

    Valleix, Sophie; Verona, Guglielmo; Jourde-Chiche, Noémie; Nédelec, Brigitte; Mangione, P. Patrizia; Bridoux, Frank; Mangé, Alain; Dogan, Ahmet; Goujon, Jean-Michel; Lhomme, Marie; Dauteuille, Carolane; Chabert, Michèle; Porcari, Riccardo; Waudby, Christopher A.; Relini, Annalisa; Talmud, Philippa J.; Kovrov, Oleg; Olivecrona, Gunilla; Stoppini, Monica; Christodoulou, John; Hawkins, Philip N.; Grateau, Gilles; Delpech, Marc; Kontush, Anatol; Gillmore, Julian D.; Kalopissis, Athina D.; Bellotti, Vittorio

    2016-01-01

    Apolipoprotein C-III deficiency provides cardiovascular protection, but apolipoprotein C-III is not known to be associated with human amyloidosis. Here we report a form of amyloidosis characterized by renal insufficiency caused by a new apolipoprotein C-III variant, D25V. Despite their uremic state, the D25V-carriers exhibit low triglyceride (TG) and apolipoprotein C-III levels, and low very-low-density lipoprotein (VLDL)/high high-density lipoprotein (HDL) profile. Amyloid fibrils comprise the D25V-variant only, showing that wild-type apolipoprotein C-III does not contribute to amyloid deposition in vivo. The mutation profoundly impacts helical structure stability of D25V-variant, which is remarkably fibrillogenic under physiological conditions in vitro producing typical amyloid fibrils in its lipid-free form. D25V apolipoprotein C-III is a new human amyloidogenic protein and the first conferring cardioprotection even in the unfavourable context of renal failure, extending the evidence for an important cardiovascular protective role of apolipoprotein C-III deficiency. Thus, fibrate therapy, which reduces hepatic APOC3 transcription, may delay amyloid deposition in affected patients. PMID:26790392

  1. D25V apolipoprotein C-III variant causes dominant hereditary systemic amyloidosis and confers cardiovascular protective lipoprotein profile.

    PubMed

    Valleix, Sophie; Verona, Guglielmo; Jourde-Chiche, Noémie; Nédelec, Brigitte; Mangione, P Patrizia; Bridoux, Frank; Mangé, Alain; Dogan, Ahmet; Goujon, Jean-Michel; Lhomme, Marie; Dauteuille, Carolane; Chabert, Michèle; Porcari, Riccardo; Waudby, Christopher A; Relini, Annalisa; Talmud, Philippa J; Kovrov, Oleg; Olivecrona, Gunilla; Stoppini, Monica; Christodoulou, John; Hawkins, Philip N; Grateau, Gilles; Delpech, Marc; Kontush, Anatol; Gillmore, Julian D; Kalopissis, Athina D; Bellotti, Vittorio

    2016-01-21

    Apolipoprotein C-III deficiency provides cardiovascular protection, but apolipoprotein C-III is not known to be associated with human amyloidosis. Here we report a form of amyloidosis characterized by renal insufficiency caused by a new apolipoprotein C-III variant, D25V. Despite their uremic state, the D25V-carriers exhibit low triglyceride (TG) and apolipoprotein C-III levels, and low very-low-density lipoprotein (VLDL)/high high-density lipoprotein (HDL) profile. Amyloid fibrils comprise the D25V-variant only, showing that wild-type apolipoprotein C-III does not contribute to amyloid deposition in vivo. The mutation profoundly impacts helical structure stability of D25V-variant, which is remarkably fibrillogenic under physiological conditions in vitro producing typical amyloid fibrils in its lipid-free form. D25V apolipoprotein C-III is a new human amyloidogenic protein and the first conferring cardioprotection even in the unfavourable context of renal failure, extending the evidence for an important cardiovascular protective role of apolipoprotein C-III deficiency. Thus, fibrate therapy, which reduces hepatic APOC3 transcription, may delay amyloid deposition in affected patients.

  2. Identification of a new structural variant of human apolipoprotein E, E2(Lys146 leads to Gln), in a type III hyperlipoproteinemic subject with the E3/2 phenotype.

    PubMed Central

    Rall, S C; Weisgraber, K H; Innerarity, T L; Bersot, T P; Mahley, R W; Blum, C B

    1983-01-01

    A type III hyperlipoproteinemic subject having the apolipoprotein E (apo E) phenotype E3/2 was identified. From isoelectric focusing experiments in conjunction with cysteamine treatment (a method that measures cysteine content in apo E), the E2 isoform of this subject was determined to have only one cysteine residue, in contrast to all previously studied E2 apoproteins, which had two cysteines. This single cysteine was shown to be at residue 112, the same site at which it occurs in apo E3. From amino acid and sequence analyses, it was determined that this apo E2 differed from apo E3 by the occurrence of glutamine rather than lysine at residue 146. When phospholipid X protein recombinants of the subject's isolated E3 and E2 isoforms were tested for their ability to bind to the human fibroblast apo-B,E receptor, it was found that the E3 bound normally (compared with an apo E3 control) but that the E2 had defective binding (approximately 40% of normal). Although they contained E3 as well as E2, the beta-very low density lipoproteins (beta-VLDL) from this subject were very similar in character to the beta-VLDL from an E2/2 type III hyperlipoproteinemic subject; similar subfractions could be obtained from each subject and were shown to have a similar ability to stimulate cholesteryl ester accumulation in mouse peritoneal macrophages. The new apo E2 variant has also been detected in a second type III hyperlipoproteinemic subject. Images PMID:6313758

  3. Potential roles of placental human beta-defensin-3 and apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3G in prevention of intrauterine transmission of hepatitis B virus.

    PubMed

    Bai, Xiaoxia; Tian, Ting; Wang, Peng; Yang, Xiaofu; Wang, Zhengping; Dong, Minyue

    2015-03-01

    Approximately 5% of newborns were infected by hepatitis B virus (HBV) via intrauterine transmission and this is the main reason for high prevalence of HBV in endemic regions. However, the mechanisms by which intrauterine transmission is avoided in most cases remain elusive and placental natural anti-microbial factors may play a role in the prevention of HBV intrauterine transmission. The expression levels of human β-defensin-3 (HBD-3), apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3G (A3G) and mannose binding lectin (MBL) were determined in the placenta of 30 HBV-seronegative pregnant women (controls), 7 HBV-seropositive pregnant women with infants infected via intrauterine transmission (infected group) and 30 HBV-seropositive pregnant women with non-infected infants (non-infected group). The expression of HBD-3, A3G, and MBL of placental trophoblast cell line Swan71 was determined after exposed to HBV. There were significant differences in placental HBD-3 and A3G levels among three groups, but the expression of MBL did not significantly differ. The expressions of HBD-3 and A3G were higher in non-infected group than controls and infected group, but not significantly different between infected group and controls. The exposure to HBV increased significantly the expression of HBD-3, A3G, and MBL by Swan 71. It may be concluded HBV up-regulates HBD-3 and A3G expression in vivo and in vitro in placental trophoblast and lack of this up-regulation is possibly associated with intrauterine transmission of HBV.

  4. Changes of Apolipoprotein M Gene Expression During the Cell Differentiation and Apoptosis Induced by Simvastatin in Combination with All-Trans Retinoic Acid in Human Promyelocytic Leukemia Cell Line NB4.

    PubMed

    Gu, Weiying; Xiang, Lili; Jiang, Tingxiu; Luo, Guanghua; Wei, Jiang; Cen, Jiannong; Chen, Zixing; Qiu, Guoqiang; Zeng, Mei; Zhang, Xiaoying

    2016-03-01

    We examined the effect of simvastatin (SV) alone and in combination with all-trans retinoic acid (ATRA) on proliferation, differentiation, apoptosis and apolipoprotein M (apoM) expression in the human promyelocytic leukemia cell line NB4. The NB4 cells were incubated with 10 μM Simvastatin (10SV) and 0.5 μM ATRA alone or in combination, taking NB4 cells without any treatment as normal controls. The cells of different groups were collected at 24, 48 and 72 h post-incubation for further detection. Their morphological changes were observed after Wright stain. MTT method was used to assay the growth inhibition rate and flow cytometry to detect CD11b expression level and the early stage apoptosis ratio. Real-time quantitative reverse transcriptase-polymerase chain reaction was used to detect the apoM gene expression levels. As expected 0.5 μM ATRA did not affect proliferation or apoptosis, strongly induced differentiation and decreased apoM expression. 10SV inhibited proliferation, increased apoptosis, induced differentiation and increased apoM expression in a time-dependent manner. The addition of ATRA to SV did not increase the effect of SV on proliferation and apoptosis, but increased the effect of SV on differentiation. And completely abrogated the effect of SV on apoM expression. Together these results show that SV has anti-leukemic properties by itself and that combined therapy may have a place in the current anti-leukemic arsenal.

  5. Evaluation of lipids, lipoproteins and apolipoproteins concentrations in cord blood serum of newborns from rural and urban environments.

    PubMed

    Pac-Kozuchowska, Elzbieta

    2007-01-01

    The purpose of the present study was to check the influence of rural and urban environments on some of the parameters of lipids metabolism in the cord blood serum in healthy newborns, as well as the evaluation of the concentration of lipids, lipoproteins and apolipoproteins in the cord blood serum with relation to risk factors of atherosclerosis in the family of the studied newborns. The study included 75 newborns (37 from rural areas and 38 from urban areas). Newborns weight and length were recorded at birth. On the basis of the family history taken from the mothers, the atherosclerosis risk factors were established in the families of the studied newborns. In all of the studied newborns, concentration of triglycerides, total cholesterol and LDL, VLDL and HDL cholesterol as well as of apolipoproteins (apo-Al, apo-B) in the cord blood serum sampled soon after birth were performed. No statistically significant differences between the mean levels of triglycerides, total cholesterol and cholesterol of fractions: LDL, VLDL, HDL and apolipoproteins (apo-AI, apo-B) in the cord blood serum in the newborns from rural and urban areas were found. However, when analysing the concentration of parameters of lipid metabolism in cord blood serum in newborns with regard to gender, higher concentrations of total cholesterol, LDL cholesterol and apo-AI in female newborns from rural areas, and higher HDL cholesterol and apo-AI in female newborns from urban regions were confirmed. When analysing the concentration of lipids and lipoproteins in cord blood serum in newborns from families with risk factors confirmed as compared to the families without that risk, both in the rural and urban regions no significant differences were confirmed. The studies have not proved any significant differences between the levels of lipids, lipoproteins and apolipoproteins in the cord blood serum in newborns from rural and urban areas.

  6. Transcriptional Regulation of Apolipoprotein A5 Gene Expression by the Nuclear Receptor ROR alpha

    SciTech Connect

    Genoux, Annelise; Dehondt, Helene; Helleboid-Chapman, Audrey; Duhem, Christian; Hum, Dean W.; Martin, Genevieve; Pennacchio, Len; Staels, Bart; Fruchart-Najib, Jamila; Fruchart, Jean-Charles

    2004-10-01

    Apolipoprotein A5 has recently been identified as a crucial determinant of plasma triglyceride levels. Our results showed that RORa up-regulates human APOA5 but has no effect on mouse apoa5 promoter. These data suggest an additional important physiological role for RORa in the regulation of genes involved in plasma triglyceride homeostasis in human and probably in the development of atherosclerosis

  7. Increased apolipoprotein E and c-fms gene expression without elevated interleukin 1 or 6 mRNA levels indicates selective activation of macrophage functions in advanced human atheroma.

    PubMed Central

    Salomon, R N; Underwood, R; Doyle, M V; Wang, A; Libby, P

    1992-01-01

    Cells found within atherosclerotic lesions can produce in culture protein mediators that may participate in atherogenesis. To test whether human atheromata actually contain transcripts for certain of these genes, we compared levels of mRNAs in carotid or coronary atheromata and in nonatherosclerotic human vessels by polymerase chain reaction (PCR) amplification of cDNAs reverse-transcribed from RNA. We measured PCR products (generated during exponential amplification) by incorporation of 32P-labeled primers. Levels of interleukin 1 alpha, 1 beta, or 6 mRNAs in plaques and controls did not differ. Compared to uninvolved vessels, plaques did contain higher levels of mRNA encoding platelet-derived growth factor A chain (42 +/- 24 vs. 12 +/- 10 fmol of product; mean +/- SD; n = 8 and 8, respectively; P = 0.007) and B chain (41 +/- 36 vs. 4 +/- 3 fmol of product, n = 14 and 6, respectively; P = 0.024). Atherosclerotic lesions consistently had much higher levels of apolipoprotein E (apoE) mRNA than did control vessels (131 +/- 71 vs. 5 +/- 3 fmol of product; n = 12 and 10, respectively; P less than 0.001). Direct RNA blot analyses confirmed elevated levels of apoE mRNA in plaque extracts. To test whether mononuclear phagocytes might be a source of the apoE mRNA, we studied a selective marker for cells of the monocytic lineage, the c-fms protooncogene, which encodes the receptor for macrophage colony-stimulating factor. Plaques also contained elevated levels of c-fms mRNA (30 +/- 17 vs. 5 +/- 3 fmol of product; n = 10 and 7, respectively; P = 0.002). Immunohistochemical colocalization demonstrated apoE protein in association with macrophages in plaques, whereas nonatherosclerotic vessels showed no immunoreactive apoE. ApoE produced locally in atheroma might modulate the functions of lesional T cells or promote "reverse cholesterol transport" by associating with high density lipoprotein particles, thus targeting them for peripheral uptake. Macrophages within the advanced

  8. CASCADE: Introducing AI into CBT.

    ERIC Educational Resources Information Center

    Hendley, R. J.; Jurascheck, N.

    1992-01-01

    Discusses changes in training requirements of commerce and industry in the United Kingdom and describes a project, CASCADE, that was developed to investigate and implement the introduction of artificial intelligence (AI) techniques into computer-based training (CBT). An overview of pilot projects in higher education settings is provided. (eight…

  9. Apolipoprotein A-I modulates regulatory T cells in autoimmune LDLr-/-, ApoA-I-/- mice.

    PubMed

    Wilhelm, Ashley J; Zabalawi, Manal; Owen, John S; Shah, Dharika; Grayson, Jason M; Major, Amy S; Bhat, Shaila; Gibbs, Dwayne P; Thomas, Michael J; Sorci-Thomas, Mary G

    2010-11-12

    The immune system is complex, with multiple layers of regulation that serve to prevent the production of self-antigens. One layer of regulation involves regulatory T cells (Tregs) that play an essential role in maintaining peripheral self-tolerance. Patients with autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis have decreased levels of HDL, suggesting that apoA-I concentrations may be important in preventing autoimmunity and the loss of self-tolerance. In published studies, hypercholesterolemic mice lacking HDL apoA-I or LDLr(-/-), apoA-I(-/-) (DKO), exhibit characteristics of autoimmunity in response to an atherogenic diet. This phenotype is characterized by enlarged cholesterol-enriched lymph nodes (LNs), as well as increased T cell activation, proliferation, and the production of autoantibodies in plasma. In this study, we investigated whether treatment of mice with lipid-free apoA-I could attenuate the autoimmune phenotype. To do this, DKO mice were first fed an atherogenic diet containing 0.1% cholesterol, 10% fat for 6 weeks, after which treatment with apoA-I was begun. Subcutaneous injections of 500 μg of lipid-free apoA-I was administered every 48 h during the treatment phase. These and control mice were maintained for an additional 6 weeks on the diet. At the end of the 12-week study, DKO mice showed decreased numbers of LN immune cells, whereas Tregs were proportionately increased. Accompanying this increase in Tregs was a decrease in the percentage of effector/effector memory T cells. Furthermore, lipid accumulation in LN and skin was reduced. These results suggest that treatment with apoA-I reduces inflammation in DKO mice by augmenting the effectiveness of the LN Treg response.

  10. Sequence-specific apolipoprotein A-I effects on lecithin:cholesterol acyltransferase activity.

    PubMed

    Dergunov, Alexander D

    2013-06-01

    Existing kinetic data of cholesteryl ester formation by lecithin:cholesterol acyltransferase in discoidal high-density lipoproteins with 34 mutations of apoA-I that involved all putative helices were grouped by cluster analysis into four noncoincident regions with mutations both without any functional impairment and with profound isolated (V- and K-mutations) or common (VK-mutations) effect on V(max)(app) and K(m)(app). Data were analyzed with a new kinetic model of LCAT activity at interface that exploits the efficiency of LCAT binding to the particle, particle dimensions, and surface concentrations of phosphatidylcholine and cholesterol. V-mutations with major location in the central part and C-domain affected the second-order rate constant of cholesteryl ester formation at the solvolysis of acyl-enzyme intermediate by cholesterol as nucleophile. The central region in apoA-I sequence is suggested to influence the proper positioning of cholesterol molecule toward LCAT active center with major contribution of arginine residue(s). K-mutations with major location in N-domain may affect binding and stability of enzyme-phosphatidylcholine complex. VK-mutations may possess mixed effects; the independent binding measurement may segregate individual steps.

  11. HDL-apolipoprotein A-I exchange is independently associated with cholesterol efflux capacity

    PubMed Central

    Borja, Mark S.; Ng, Kit F.; Irwin, Angela; Hong, Jaekyoung; Wu, Xing; Isquith, Daniel; Zhao, Xue-Qiao; Prazen, Bryan; Gildengorin, Virginia; Oda, Michael N.; Vaisar, Tomáš

    2015-01-01

    HDL is the primary mediator of cholesterol mobilization from the periphery to the liver via reverse cholesterol transport (RCT). A critical first step in this process is the uptake of cholesterol from lipid-loaded macrophages by HDL, a function of HDL inversely associated with prevalent and incident cardiovascular disease. We hypothesized that the dynamic ability of HDL to undergo remodeling and exchange of apoA-I is an important and potentially rate-limiting aspect of RCT. In this study, we investigated the relationship between HDL-apoA-I exchange (HAE) and serum HDL cholesterol (HDL-C) efflux capacity. We compared HAE to the total and ABCA1-specific cholesterol efflux capacity of 77 subjects. We found that HAE was highly correlated with both total (r = 0.69, P < 0.0001) and ABCA1-specific (r = 0.47, P < 0.0001) efflux, and this relationship remained significant after adjustment for HDL-C or apoA-I. Multivariate models of sterol efflux capacity indicated that HAE accounted for approximately 25% of the model variance for both total and ABCA1-specific efflux. We conclude that the ability of HDL to exchange apoA-I and remodel, as measured by HAE, is a significant contributor to serum HDL efflux capacity, independent of HDL-C and apoA-I, indicating that HDL dynamics are an important factor in cholesterol efflux capacity and likely RCT. PMID:26254308

  12. Role of apolipoprotein E in neurodegenerative diseases

    PubMed Central

    Giau, Vo Van; Bagyinszky, Eva; An, Seong Soo A; Kim, Sang Yun

    2015-01-01

    Apolipoprotein E (APOE) is a lipid-transport protein abundantly expressed in most neurons in the central nervous system. APOE-dependent alterations of the endocytic pathway can affect different functions. APOE binds to cell-surface receptors to deliver lipids and to the hydrophobic amyloid-β peptide, regulating amyloid-β aggregations and clearances in the brain. Several APOE isoforms with major structural differences were discovered and shown to influence the brain lipid transport, glucose metabolism, neuronal signaling, neuroinflammation, and mitochondrial function. This review will summarize the updated research progress on APOE functions and its role in Alzheimer’s disease, Parkinson’s disease, cardiovascular diseases, multiple sclerosis, type 2 diabetes mellitus, Type III hyperlipoproteinemia, vascular dementia, and ischemic stroke. Understanding the mutations in APOE, their structural properties, and their isoforms is important to determine its role in various diseases and to advance the development of therapeutic strategies. Targeting APOE may be a potential approach for diagnosis, risk assessment, prevention, and treatment of various neurodegenerative and cardiovascular diseases in humans. PMID:26213471

  13. Safe and sustained overexpression of functional apolipoprotein A-I/high-density lipoprotein in apolipoprotein A-I-null mice by muscular adeno-associated viral serotype 8 vector gene transfer.

    PubMed

    Cimmino, Giovanni; Chen, Wei; Speidl, Walter S; Giannarelli, Chiara; Ibanez, Borja; Fuster, Valentin; Hajjar, Roger; Walsh, Christopher E; Badimon, Juan J

    2009-11-01

    High levels of high-density lipoprotein (HDL) have protective effects against atherosclerosis and cardiovascular diseases. The postulated mechanism of action for these benefits is an enhanced reverse cholesterol transport. Apolipoprotein A-I (ApoA-I) is the major protein of HDL. The clinical benefits of raising ApoA-I/HDL have been clearly established by clinical and epidemiological studies. Despite these observations, there are not very effective pharmacological means for raising HDL. ApoA-I gene delivery by viral vectors seems a promising strategy to raise ApoA-I/HDL levels. Sustained gene expression in animals and humans has been attained using adeno-associated viral (AAV) vectors. The aim of the present study was to determine the efficiency, safety, and biological activity of human ApoA-I intramuscularly delivered using an AAV vector in mice. AAV serotype 8 vectors encoding for human ApoA-I transgene were administered intraportally and intramuscularly in ApoA-I- deficient animals. ApoA-I levels were measured every 2 weeks post administration. The effectiveness of the generated HDL was tested in vitro in cholesterol-loaded macrophages. The administration of the vectors resulted in a significant and sustained increase in ApoA-I and HDL plasma levels for up to 16 weeks at similar extent by both routes of administration. Activity of the generated HDL in removal of cholesterol from cholesterol-loaded macrophages was similar in both groups. Our data suggest that intramuscular AAV8-mediated gene transfer of human ApoA-I results in a significant and maintained increase in ApoA-I and functional HDL.

  14. AIS Investigation of Agricultural Monocultures

    NASA Technical Reports Server (NTRS)

    Wood, B. L.; Wrigley, R. C.

    1985-01-01

    Airborne Imaging Spectrometer (AIS) data were acquired over an agricultural area in eastern San Joaquin County, California in July, 1984. Cover type information was subsequently collected for all fields along this flight line. The lack of detailed ground data on individual fields, however, limited AIS data analysis to a qualitative comparison of the spectral reflectance curves for a total of nine cover types. Based on this analysis, it appears that cover types with a positive slope in the 1550 to 1700 nm region have a higher spectral response in the 1200 to 1300 nm region compared to those cover types with a negative slope in the 1550 to 1700 nm region. Within cover type, spectral variability was also found to be greater than that between cover types. Given the lack of additional field data, the reason for these differences is a matter of speculation.

  15. Formal verification of AI software

    NASA Technical Reports Server (NTRS)

    Rushby, John; Whitehurst, R. Alan

    1989-01-01

    The application of formal verification techniques to Artificial Intelligence (AI) software, particularly expert systems, is investigated. Constraint satisfaction and model inversion are identified as two formal specification paradigms for different classes of expert systems. A formal definition of consistency is developed, and the notion of approximate semantics is introduced. Examples are given of how these ideas can be applied in both declarative and imperative forms.

  16. Nitric oxide-releasing agent, LA419, reduces atherogenesis in apolipoprotein E-deficient mice.

    PubMed

    Carnicer, Ricardo; Guillén, Natalia; Arbonés-Mainar, José M; Navarro, María A; Guzmán, Mario A; Barranquero, Cristina; Arnal, Carmen; Gascón, Sonia; Acín, Sergio; Mourelle, Marisabel; Osada, Jesús

    2009-05-01

    LA419 is a novel nitric oxide-donor with antioxidant properties. The effect of this compound on the development of atherosclerosis was investigated in apolipoprotein E-deficient mice. Male mice were randomized to receive vehicle or 5 mg/kg/day LA419 for 12 weeks. At the end of this period, plasma lipid and lipoprotein parameters, oxidative stress markers and hepatic fat, and mRNA levels were measured as well as en face and cross-sectional lesion areas of the aorta. Data showed that LA419 administration reduced atherosclerotic foci and cross-sectional lesion areas by decreasing the intimae presence of macrophage-derived foam cells despite an increase in plasma cholesterol. This agent induced a significant reduction in body weight gain and mass of adipose tissue. Furthermore, compared with placebo, LA419 administration significantly reduced plasma triglycerides and apolipoprotein C-III levels as well as systemic oxidative stress, estimated by plasma 8-isoprostane. Conversely, nonesterified fatty acid and HDL cholesterol levels remained unchanged, as well as apolipoproteins A-I, A-IV, and B and paraoxonase activity. Plasma triglycerides were significantly associated with plasma levels of apolipoprotein C-III and hepatic Fsp27 mRNA expression. These results indicate that administration of LA419 modulates lesion development. These actions are partly independent of total cholesterol as well as HDL particles and related to triglyceridemia and oxidative stress. Hypotriglyceridemia is associated with an equal number of apoB-containing particles. Hence, LA419 administration could be used as a safe alternative to control the metabolic syndrome and atherosclerosis.

  17. Charged Amino Acid Residues 997–1000 of Human Apolipoprotein B100 Are Critical for the Initiation of Lipoprotein Assembly and the Formation of a Stable Lipidated Primordial Particle in McA-RH7777 Cells*

    PubMed Central

    Manchekar, Medha; Richardson, Paul E.; Sun, Zhihuan; Liu, Yanwen; Segrest, Jere P.; Dashti, Nassrin

    2008-01-01

    We previously demonstrated that a portion, or perhaps all, of the residues between 931 and 1000 of apolipoprotein (apo) B100 are required for the initiation of apoB-containing particle assembly. Based on our structural model of the first 1000 residues of apoB (designated as apoB:1000), we hypothesized that this domain folds into a three-sided lipovitellin-like “lipid pocket” via a hairpin-bridge mechanism. We proposed that salt bridges are formed between four tandem charged residues 717–720 in the turn of the hairpin bridge and four tandem complementary residues 997–1000 located at the C-terminal end of the model. To identify the specific motif within residues 931 and 1000 that is critical for apoB particle assembly, apoB:956 and apoB:986 were produced. To test the hairpin-bridge hypothesis, the following mutations were made: 1) residues 997–1000 deletion (apoB:996), 2) residues 717–720 deletion (apoB:1000Δ717–720), and 3) substitution of charged residues 997–1000 with alanines (apoB:996 + 4Ala). Characterization of particles secreted by stable transformants of McA-RH7777 cells demonstrated the following. 1) ApoB:956 did not form stable particles and was secreted as large lipid-rich aggregates. 2) ApoB:986 formed both a lipidated particle that was denser than HDL3 and large lipid-rich aggregates. 3) Compared with wild-type apoB:1000, apoB:1000Δ717–720 displayed the following: (i) significantly diminished capacity to form intact lipidated particles and (ii) increased propensity to form large lipid-rich aggregates. 4) In striking contrast to wild-type apoB:1000, (i) apoB:996 and apoB:996 + 4Ala were highly susceptible to intracellular degradation, (ii) only a small proportion of the secreted proteins formed stable HDL3-like lipoproteins, and (iii) a majority of the secreted proteins formed large lipid-rich aggregates. We conclude that the first 1000 amino acid residues of human apoB100 are required for the initiation of nascent apo

  18. Two amino acid substitutions in apolipoprotein B are in complete allelic association with the antigen group (x/y) polymorphism: Evidence for little recombination in the 3' end of the human gene

    PubMed Central

    Dunning, Alison M.; Renges, Helmut-H.; Xu, Chun-Fang; Peacock, Rachel; Brasseur, Robert; Laxer, Gerald; Tikkanen, Matti J.; Bütler, Réné; Saha, N.; Hamsten, Anders; Rosseneu, Maryvonne; Talmud, Philippa; Humphries, Steve E.

    1992-01-01

    We report the identification of an A-to-G base change, in exon 29 of the apolipoprotein B (apo B) gene, that results in the substitution of serine for asparagine at residue 4311 of mature apo B100. In a recent publication, Huang et al. have reported a C-to-T base change in exon 26 that causes the substitution of leucine for proline at residue 2712 of apo B. We have found complete linkage disequilibrium between the alleles at both these sites and an immunochemical polymorphism of LDL designated antigen group (x/y) (Ag(x/y)) in a sample of 118 Finnish individuals. This implies that either one of these substitutions–or both of them combined–could be the molecular basis of the Ag(x/y) antigenic determinants, with the allele encoding serine4311 plus leucine2712 representing the Ag(x) epitope, and that encoding asparagine4311 plus proline2712 the Ag(y) epitope. In a sample of 90 healthy Swedish individuals the Leu2712/Ser4311 allele is associated both with reduced serum levels of LDL-cholesterol and apo B and with raised levels of HDL. However, these differences are of smaller effect than those associated with the XbaI RFLP of the apo B gene in this sample. We have also genotyped 523 individuals from European, Asian, Chinese, and Afro-Caribbean populations and have found complete association between the sites encoding residues 2712 and 4311 in all of these samples, although there are large allele frequency differences between these populations. In addition, there is strong linkage disequilibrium with allelic association between the alleles of these sites and those of the XbaI RFLP in all the populations examined. Taken together, these data suggest that, since the divergence of the major ethnic groups, there has been little or no recombination in the 3' end of the human apo B gene. ImagesFigure 1Figure 2Figure 3 PMID:1370364

  19. Situated, strategic, and AI-Enhanced technology introduction to healthcare.

    PubMed

    Bushko, Renata G

    2005-01-01

    We work hard on creating AI-wings for physicians to let them fly higher and faster in diagnosing patients--a task that physicians do not want to automate. What we do not work hard on is determining the ENVIRONMENT in which physicians' AI wings are supposed to function. It seems to be a job for social/business analysts that have their own separate kingdom. For the sake of all of us (potential patients!) social/business consultants and their methodologies should not be treated as a separate kingdom. The most urgent task is to achieve synergy between (1) AI/Fuzzy/Neural research, (2) Applied medical AI, (3) Social/Business research on medical institutions. We need this synergy in order to assure humanistic medical technology; technology flexible and sensitive enough to facilitate healthcare work while leaving space for human pride and creativity. In order to achieve humanistic technology, designers should consider the impact of technological breakthroughs on the organizations in which this technology will function and the nature of work of humans destined to use this technology. Situated (different for each organization), Strategic (based on an in-depth knowledge of Healthcare business), and AI-Enhanced (ended with a dynamic model) method for introducing technology to Healthcare allows identifying areas where technology can make medical work easier. Using this method before automating human work will get us closer to the ideal where there is no discontinuity between design and use of programs; where the technology matches users' needs perfectly--the world with humanistic technology and healthcare workers with AI-wings.

  20. Refined physical map of the human PAX2/HOX11/NFKB2 cancer gene region at 10q24 and relocalization of the HPV6AI1 viral integration site to 14q13.3-q21.1

    PubMed Central

    Gough, Sheryl M; McDonald, Margaret; Chen, Xiao-Ning; Korenberg, Julie R; Neri, Antonino; Kahn, Tomas; Eccles, Michael R; Morris, Christine M

    2003-01-01

    Background Chromosome band 10q24 is a gene-rich domain and host to a number of cancer, developmental, and neurological genes. Recurring translocations, deletions and mutations involving this chromosome band have been observed in different human cancers and other disease conditions, but the precise identification of breakpoint sites, and detailed characterization of the genetic basis and mechanisms which underlie many of these rearrangements has yet to be resolved. Towards this end it is vital to establish a definitive genetic map of this region, which to date has shown considerable volatility through time in published works of scientific journals, within different builds of the same international genomic database, and across the differently constructed databases. Results Using a combination of chromosome and interphase fluorescent in situ hybridization (FISH), BAC end-sequencing and genomic database analysis we present a physical map showing that the order and chromosomal orientation of selected genes within 10q24 is CEN-CYP2C9-PAX2-HOX11-NFKB2-TEL. Our analysis has resolved the orientation of an otherwise dynamically evolving assembly of larger contigs upstream of this region, and in so doing verifies the order and orientation of a further 9 cancer-related genes and GOT1. This study further shows that the previously reported human papillomavirus type 6a DNA integration site HPV6AI1 does not map to 10q24, but that it maps at the interface of chromosome bands 14q13.3-q21.1. Conclusions This revised map will allow more precise localization of chromosome rearrangements involving chromosome band 10q24, and will serve as a useful baseline to better understand the molecular aetiology of chromosomal instability in this region. In particular, the relocation of HPV6AI1 is important to report because this HPV6a integration site, originally isolated from a tonsillar carcinoma, was shown to be rearranged in other HPV6a-related malignancies, including 2 of 25 genital condylomas

  1. AI in Reverse: Computer Tools That Become Cognitive.

    ERIC Educational Resources Information Center

    Salomon, Gavriel

    The question of whether human thinking can come to simulate computer intelligence--i.e., AI in reverse--is addressed in this paper. Examples are given of three computer tools which perform several functions that constitute an intellectual partnership between student and tool. Such functions include: (1) assuming part of the intellectual burden in…

  2. Apolipoprotein E: the resilience gene.

    PubMed

    James, Lisa M; Engdahl, Brian E; Georgopoulos, Apostolos P

    2017-03-15

    The apolipoprotein E (apoE) gene has been implicated in various conditions, most notably Alzheimer's disease and coronary artery disease. A predisposing role of the apoE4 isoform and a protective role of apoE2 isoform in those diseases have been documented. Here we investigated the role of apoE in resilience to trauma. Three hundred and forty-three US veterans were genotyped for apoE and were assessed for their lifetime trauma exposure (trauma score, T) and severity of posttraumatic stress disorder symptoms (PCL). The ratio PCL/T indicates sensitivity to trauma; hence, its inverse indicates resilience, R, to trauma. We found a significantly higher resilience in participants with apoE genotype containing the E2 allele (E2/2, E2/3) as compared to participants with the E4 allele (E4/4, E4/3). In addition, when the categorical apoE genotype was reexpressed as the number of cysteine residues per apoE mole (CysR/mole), a highly significant positive association was found between resilience and CysR/mole, such that resilience was systematically higher as the number of CysR/mole increased, from zero CysR/mole in E4/4 to four CysR/mole in E2/2. These findings demonstrate the protective role of the CysR/mole apoE in resilience to trauma: the more CysR/mole, the higher the resilience. Thus, they are in accord with other findings pointing to a generally protective role of increasing number of CysR/mole (from E4/4 to E2/2) in other diseases. However, unlike other conditions (e.g., Alzheimer's disease and coronary artery disease), resilience to trauma is not a disease but an adaptive response to trauma. Therefore, the effects of apoE seem to be more pervasive along the CysR/mole continuum, most probably reflecting underlying effects on brain synchronicity and its variability that we have documented previously (Leuthold et al., Exp Brain Res 226:525-536, 2013).

  3. Apolipoprotein D (APOD) is a putative biomarker of androgen receptor function in androgen insensitivity syndrome.

    PubMed

    Appari, Mahesh; Werner, Ralf; Wünsch, Lutz; Cario, Gunnar; Demeter, Janos; Hiort, Olaf; Riepe, Felix; Brooks, James D; Holterhus, Paul-Martin

    2009-06-01

    Androgen insensitivity syndrome (AIS) is the most common cause of disorders of sex development usually caused by mutations in the androgen receptor (AR) gene. AIS is characterized by a poor genotype-phenotype correlation, and many patients with clinically presumed AIS do not seem to have mutations in the AR gene. We therefore aimed at identifying a biomarker enabling the assessment of the cellular function of the AR as a transcriptional activator. In the first step, we used complementary DNA (cDNA) microarrays for a genome-wide screen for androgen-regulated genes in two normal male primary scrotal skin fibroblast strains compared to two labia majora fibroblast strains from 46,XY females with complete AIS (CAIS). Apolipoprotein D (APOD) and two further transcripts were significantly upregulated by dihydrotestosterone (DHT) in scrotum fibroblasts, while CAIS labia majora cells were unresponsive. Microarray data were well correlated with quantitative real-time polymerase chain reaction (qRT-PCR; R = 0.93). Subsequently, we used qRT-PCR in independent new cell cultures and confirmed the significant DHT-dependent upregulation of APOD in five normal scrotum strains [13.5 +/- 8.2 (SD)-fold] compared with three CAIS strains (1.2 +/- 0.7-fold, p = 0.028; t test) and six partial androgen insensitivity syndrome strains (2 +/- 1.3-fold, p = 0.034; t test). Moreover, two different 17ss-hydroxysteroid dehydrogenase III deficiency labia majora strains showed APOD induction in the range of normal scrotum (9.96 +/- 1.4-fold), supporting AR specificity. Therefore, qRT-PCR of APOD messenger RNA transcription in primary cultures of labioscrotal skin fibroblasts is a promising tool for assessing AR function, potentially allowing a function-based diagnostic evaluation of AIS in the future.

  4. Mapping AIS coverage for trusted surveillance

    NASA Astrophysics Data System (ADS)

    Lapinski, Anna-Liesa S.; Isenor, Anthony W.

    2010-10-01

    Automatic Identification System (AIS) is an unattended vessel reporting system developed for collision avoidance. Shipboard AIS equipment automatically broadcasts vessel positional data at regular intervals. The real-time position and identity data from a vessel is received by other vessels in the area thereby assisting with local navigation. As well, AIS broadcasts are beneficial to those concerned with coastal and harbour security. Land-based AIS receiving stations can also collect the AIS broadcasts. However, reception at the land station is dependent upon the ship's position relative to the receiving station. For AIS to be used as a trusted surveillance system, the characteristics of the AIS coverage area in the vicinity of the station (or stations) should be understood. This paper presents some results of a method being investigated at DRDC Atlantic, Canada) to map the AIS coverage characteristics of a dynamic AIS reception network. The method is shown to clearly distinguish AIS reception edges from those edges caused by vessel traffic patterns. The method can also be used to identify temporal changes in the coverage area, an important characteristic for local maritime security surveillance activities. Future research using the coverage estimate technique is also proposed to support surveillance activities.

  5. USACE AIS Transmit Technical Support Summary Report

    DTIC Science & Technology

    2014-09-01

    USACE AIS Transmit Technical Support Summary Report Distribution Statement A: Approved for public release; distribution is unlimited...September 2014 Report No. CD-D-09-15 USACE AIS Transmit Technical Support Summary Report ii UNCLAS//Public | CG-926 RDC | I. Gonin et al. Public...States Coast Guard Research & Development Center 1 Chelsea Street New London, CT 06320 USACE AIS Transmit Technical Support Summary Report

  6. Lipid and apolipoprotein distribution as a function of density in equine plasma lipoprotein.

    PubMed

    Le Goff, D; Pastier, D; Hannan, Y; Petit, E; Ayrault-Jarrier, M; Nouvelot, A

    1989-01-01

    1. Equine lipoproteins were isolated from plasma by density gradient ultracentrifugation and apolipoprotein composition determined by SDS-polyacrylamide gel electrophoresis. 2. VLDL and IDL were present at low concentration (0.2 mg/ml). Two apoB components of Mr corresponding to human apoB-100 and one apoB-48-like component were represented in VLDL fraction. 3. LDL-1 and LDL-2 subfractions have displayed an almost equal concentration (0.4 mg/ml). Two apoB-100-like components were the major apolipoproteins in each fraction. Small amounts of apoB-48-like component were detectable in LDL-1 and LDL-2. 4. HDL-2 represented a major class of equine lipoproteins (1.8 mg/ml). ApoA-1-like component was the dominant protein in HDL-1, HDL-2 and HDL-3. Dimeric apoA-II-like components were slightly represented in HDL subfractions. 5. HDL-3 displayed the same apolipoprotein pattern as HDL-1 and HDL-2, but two further minor proteins of Mr 20,000 and 14,000 were detected. 6. VHDL represented a minor class of lipoprotein (0.2 mg/ml). ApoA-I-like component was the major apolipoprotein of VHDL. Small amounts of apoA-IV-like, apoE-like, and Mr 55,000 protein were detectable. 7. ApoC-like of Mr lower than 10,000 was represented in all equine lipoprotein classes.

  7. Endothelial cells synthesize and process apolipoprotein B.

    PubMed

    Sivaram, P; Vanni-Reyes, T; Goldberg, I J

    1996-06-21

    We reported previously that a 116-kDa lipoprotein lipase (LPL)-binding protein from endothelial cells has sequence homology to the amino-terminal region of apolipoprotein (apo) B. We now tested whether endothelial cells synthesize apoB mRNA and protein. Primers were designed to the human apoB cDNA sequence and reverse transcription polymerase chain reaction was performed using total RNA isolated from bovine and human endothelial cells. With primers to the 5' region of the apoB mRNA (amino-terminal region of apoB protein) expected size PCR products were generated from both bovine and human endothelial cells as well as from mouse liver RNA, which was used as a control. Primers designed to the 3' region of apoB mRNA generated PCR products from human endothelial cells and HepG2 cells but not from bovine or mouse cells. These data suggest that endothelial cells contain full-length apoB mRNA and that the 5' or the amino-terminal region of apoB is highly conserved from mouse to human. This was confirmed by direct sequencing of the mouse and bovine PCR products. To test whether apoB protein was produced, bovine endothelial cell proteins were metabolically labeled with [35S]methionine/cysteine or [3H]leucine and immunoprecipitated with anti-human apoB antibodies. Using extracts from cells labeled for 1 h, monoclonal antibody 47, directed to the low density lipoprotein receptor binding region of apoB, precipitated a protein of approximate molecular mass 550,000, the size of full-length apoB. Immunoprecipitation of the 550-kDa protein was abolished in the presence of added unlabeled low density lipoprotein. From cells labeled for 16 h, a 116-kDa protein was immunoprecipitated by polyclonal anti-apoB antibodies. This protein was partly released from cells by heparin treatment. Pulse-chase analysis showed that the 116-kDa fragment appeared at the same time as the full-length apoB began disappearing. The immunoprecipitated 116-kDa fragment also bound labeled LPL on ligand blot

  8. Effect of acute feeding of diets of varying fatty acid composition on intestinal apolipoprotein expression in the newborn swine.

    PubMed

    Wang, H; Zhan, R; Hunter, F; Du, J; Black, D

    1996-06-01

    The purpose of this study was to determine the effects of dietary fatty acids of varying chain lengths and degrees of saturation on intestinal apolipoprotein (apo) B and A-I expression in the newborn piglet. Two-day-old female piglets received one of three isocaloric formulas containing 48% of total calories (120 kcal/kg/24 h) as medium-chain triglycerides (MCT) from MCT oil, intermediate-chain saturated triglycerides (ICST) from coconut oil, or long-chain polyunsaturated triglycerides (LCPUT) from safflower oil by continuous duodenal infusion for 24 h. After in situ radiolabeling, jejunal and ileal mucosal apo B-48 and A-I were immunoprecipitated, and synthesis was expressed as percentage of total protein synthesis. Mucosal apo B and A-I mass was measured by ELISA as nanograms of apoprotein/microgram of total protein. Fifty percent less apo B jejunal synthesis was present in the ICST group versus the MCT and LCPUT groups (0.67 +/- 0.07, 1.19 +/- 0.20, and 1.25 +/- 0.15, respectively, mean +/- SEM, p < 0.05). Jejunal apo B mass was lower in the MCT group versus the ICST and LCPUT groups (0.10 +/- 0.02, 0.21 +/- 0.03, and 0.16 +/- 0.03, respectively, p < 0.05). Ileal apo B synthesis was lowest in the ICST group. No differences were found in ileal apo B mass. Two-fold higher jejunal apo A-I synthesis was found in the LCPUT group versus the MCT and ICST groups (14.18 +/- 1.69, 7.56 +/- 2.63, and 6.36 +/- 0.58, respectively, p < 0.01). No differences were found for jejunal apo A-I mass. In the ileum, the only difference was a higher apo A-I mass in the LCPUT group (p < 0.05). We conclude that in the newborn piglet intestinal apo B and A-I expression is acutely and differentially regulated by dietary lipid varying in fatty acid chain length and saturation. The patterns of regulation are complex and vary among specific apolipoproteins and regions of the small intestine and include co- and posttranslational mechanisms.

  9. Peptide Mimetics of Apolipoproteins Improve HDL Function

    PubMed Central

    Navab, Mohamad; Anantharamaiah, G. M.; Reddy, Srinivasa T.; Van Lenten, Brian J.; Buga, Georgette M.; Fogelman, Alan M.

    2007-01-01

    Over the past decade evidence has accumulated that suggests that the anti-inflammatory properties of HDL may be at least as important as the levels of HDL-cholesterol. The recent failure of the torcetrapib clinical trails has highlighted the potential differences between HDL-cholesterol levels and HDL function. Agents to improve HDL function including HDL anti-inflammatory properties provide a new therapeutic strategy for ameliorating atherosclerosis and other chronic inflammatory conditions related to dyslipidemia. Seeking guidance from the structure of the apolipoproteins of the plasma lipoproteins has allowed the creation of a series of polypeptides that have interesting functionality with therapeutic implications. In animal models of atherosclerosis, peptide mimetics of apolipoproteins have been shown to improve the anti-inflammatory properties of HDL, significantly reduce lesions and improve vascular inflammation and function without necessarily altering HDL-cholesterol levels. Some of these are now entering the clinical arena as interventions in pharmacologic and pharmacodynamic studies. PMID:18449337

  10. JGOMAS: New Approach to AI Teaching

    ERIC Educational Resources Information Center

    Barella, A.; Valero, S.; Carrascosa, C.

    2009-01-01

    This paper presents a new environment for teaching practical work in AI subjects. The main purpose of this environment is to make AI techniques more appealing to students and to facilitate the use of the toolkits which are currently widely used in research and development. This new environment has a toolkit for developing and executing agents,…

  11. The Relevance of AI Research to CAI.

    ERIC Educational Resources Information Center

    Kearsley, Greg P.

    This article provides a tutorial introduction to Artificial Intelligence (AI) research for those involved in Computer Assisted Instruction (CAI). The general theme is that much of the current work in AI, particularly in the areas of natural language understanding systems, rule induction, programming languages, and socratic systems, has important…

  12. Direct Transcriptional Effects of Apolipoprotein E

    PubMed Central

    Theendakara, Veena; Peters-Libeu, Clare A.; Spilman, Patricia; Poksay, Karen S.

    2016-01-01

    A major unanswered question in biology and medicine is the mechanism by which the product of the apolipoprotein E ε4 allele, the lipid-binding protein apolipoprotein E4 (ApoE4), plays a pivotal role in processes as disparate as Alzheimer's disease (AD; in which it is the single most important genetic risk factor), atherosclerotic cardiovascular disease, Lewy body dementia, hominid evolution, and inflammation. Using a combination of neural cell lines, skin fibroblasts from AD patients, and ApoE targeted replacement mouse brains, we show in the present report that ApoE4 undergoes nuclear translocation, binds double-stranded DNA with high affinity (low nanomolar), and functions as a transcription factor. Using chromatin immunoprecipitation and high-throughput DNA sequencing, our results indicate that the ApoE4 DNA binding sites include ∼1700 gene promoter regions. The genes associated with these promoters provide new insight into the mechanism by which AD risk is conferred by ApoE4, because they include genes associated with trophic support, programmed cell death, microtubule disassembly, synaptic function, aging, and insulin resistance, all processes that have been implicated in AD pathogenesis. SIGNIFICANCE STATEMENT This study shows for the first time that apolipoprotein E4 binds DNA with high affinity and that its binding sites include 1700 promoter regions that include genes associated with neurotrophins, programmed cell death, synaptic function, sirtuins and aging, and insulin resistance, all processes that have been implicated in Alzheimer's disease pathogenesis. PMID:26791201

  13. Apolipoprotein E Polymorphism in Tuberculosis Patients

    NASA Astrophysics Data System (ADS)

    Naserpour Farivar, Taghi; Sharifi Moud, Batool; Sargazi, Mansur; Moeenrezakhanlou, Alireza

    In this study, we aimed to determine the significance of association between Tuberculosis and apolipoprotein E polymorphism. The apolipoprotein E genotypes were assayed in 250 tuberculosis patients by polymerase chain reaction followed by enzymatic digestion with Hha I. The results were compared with the results of the same experiments on 250 sex and age matched control peoples. Present results showed that in studied populations, prevalence of E4 genotype was lower in controls than in patients (8 v. 13.2%; OR = 1.75, p<0.05) and prevalence of E3 genotype was high in controls than in patients (86 v.51%; OR = 0.17, p<0.05). Statistically significant difference was found between patients and controls with respect to ɛ2 allele frequencies, while ɛ2 allele frequency was found to be much less prevalent in controls (6%) than in patients (35.8%; OR = 8.72, p<0.05). Also, our study revealed that there is an association between apolipoprotein E genotypes and amplitude to tuberculosis in studied populations. However, large population-based studies are needed to understand the exact role played by the locus in causing the condition.

  14. Macrophage apoAI protects against dyslipidemia-induced dermatitis and atherosclerosis without affecting HDL.

    PubMed

    Tavori, Hagai; Su, Yan Ru; Yancey, Patricia G; Giunzioni, Ilaria; Wilhelm, Ashley J; Blakemore, John L; Zabalawi, Manal; Linton, MacRae F; Sorci-Thomas, Mary G; Fazio, Sergio

    2015-03-01

    Tissue cholesterol accumulation, macrophage infiltration, and inflammation are features of atherosclerosis and some forms of dermatitis. HDL and its main protein, apoAI, are acceptors of excess cholesterol from macrophages; this process inhibits tissue inflammation. Recent epidemiologic and clinical trial evidence questions the role of HDL and its manipulation in cardiovascular disease. We investigated the effect of ectopic macrophage apoAI expression on atherosclerosis and dermatitis induced by the combination of hypercholesterolemia and absence of HDL in mice. Hematopoietic progenitor cells were transduced to express human apoAI and transplanted into lethally irradiated LDL receptor(-/-)/apoAI(-/-) mice, which were then placed on a high-fat diet for 16 weeks. Macrophage apoAI expression reduced aortic CD4(+) T-cell levels (-39.8%), lesion size (-25%), and necrotic core area (-31.6%), without affecting serum HDL or aortic macrophage levels. Macrophage apoAI reduced skin cholesterol by 39.8%, restored skin morphology, and reduced skin CD4(+) T-cell levels. Macrophage apoAI also reduced CD4(+) T-cell levels (-32.9%) in skin-draining lymph nodes but had no effect on other T cells, B cells, dendritic cells, or macrophages compared with control transplanted mice. Thus, macrophage apoAI expression protects against atherosclerosis and dermatitis by reducing cholesterol accumulation and regulating CD4(+) T-cell levels, without affecting serum HDL or tissue macrophage levels.

  15. Anti-apolipoprotein A-1 antibodies and carotid intima-media thickness in Egyptian women with systemic lupus erythematosus.

    PubMed

    Radwan, M M; El-Lebedy, D; Fouda, R; Elsorougy, E

    2014-04-01

    The objective of the study was to evaluate anti-apolipoprotein A-I (Apo A-I) and carotid intima-media thickness (cIMT) as cardiovascular risk factors in Egyptian women with systemic lupus erythematosus (SLE). The study included 160 subjects, 80 women with SLE and 80 healthy women as a control group. Disease activity score (SLEDAI), disease damage index (SLICC/ACR), lipid profile, complement C3 and C4, high-sensitivity CRP (hsCRP), anti-dsDNA and anticardiolipin antibodies were evaluated in addition to anti-Apo A-I antibodies and cIMT. The mean age of patients was 28.35 ± 7.06 years with mean disease duration of 4.58 ± 3.36 years. Anti-Apo A-I antibody titer was significantly higher in SLE patients than in controls (mean 35.3 ± 6.8 vs. 21.4 ± 5.91 U/L; P = 0.000). Carotid ultrasound showed significantly thickened intima in SLE patients compared with control subjects (mean thickness, 0.5 ± 0.08 vs. 0.45 ± 0.06 mm; P = 0.003). Correlation studies with other cardiovascular risk factors demonstrated significant associations between anti-Apo A-I and SLEDAI, SLICC/ACR, C3 and C4. On the other hand, cIMT showed significant association with age, systolic blood pressure, hsCRP and body mass index. Thus, SLE disease activity is associated with a significant increase in anti-Apo A-I titer. Also, increased cIMT might be a cardiovascular risk factor in Egyptian patients with SLE.

  16. Behavior Modeling for Detection, Identification, Prediction, and Reaction (DIPR) in AI Systems Solutions

    NASA Astrophysics Data System (ADS)

    Goshorn, Rachel E.; Goshorn, Deborah E.; Goshorn, Joshua L.; Goshorn, Lawrence A.

    The application need for distributed artificial intelligence (AI) systems for behavior analysis and prediction is a requirement today versus a luxury of the past. The advent of distributed AI systems with large numbers of sensors and sensor types and unobtainable network bandwidth is also a key driving force. Additionally, the requirement to fuse a large number of sensor types and inputs is required and can now be implemented and automated in the AI hierarchy, and therefore, this will not require human power to observer, fuse, and interpret.

  17. Intestinal apolipoprotein synthesis in the newborn piglet.

    PubMed

    Black, D D; Rohwer-Nutter, P L

    1991-01-01

    To determine the effects of dietary and biliary lipid absorption on intestinal apo B-48 and apo A-I synthesis in the newborn piglet, 2-d-old female piglets were prepared with a duodenal infusion catheter. After recovery, animals were given either low triglyceride (Vivonex; VIV group) or high triglyceride (Intralipid; FAT group) diets by continuous intraduodenal infusion for 24 h. A bile-diverted group was also studied. Segments of proximal jejunum and distal ileum were then pulse-radiolabeled in vivo with 3H-leucine. Mucosal apo B-48 and apo A-I were immunoprecipitated, and apoprotein synthesis was expressed as percentage of total protein synthesis. Mucosal apoprotein content (ng apoprotein/microgram total protein) was measured by competitive ELISA assays. In jejunum and ileum, apo B-48 synthesis was not different in the three groups. However, apo B content increased 2.4-fold in jejunum and 1.7-fold in ileum in the FAT group compared with the VIV group. Immunoblotting revealed the majority of jejunal apo B to be apo B-48, not apo B-100 from contaminating plasma lipoproteins, in all three experimental groups. Bile-diverted animals had decreased jejunal apo B content compared with the VIV group. Jejunal apo A-I synthesis and content were approximately 2-fold higher in FAT animals compared with the VIV group. Although ileal apo A-I synthesis was also 2-fold higher in the FAT group, apo A-I content was not different from the VIV group. Neither jejunal nor ileal apo A-I synthesis was significantly affected by bile diversion, even though jejunal apo A-I content was decreased by over two thirds compared with the VIV animals. In the newborn piglet, intestinal synthesis of apo B-48 and apo A-I is differentially regulated by luminal lipid absorption. Although fat feeding and bile diversion regulate mucosal apo B-48 content, synthesis is unchanged, indicating a posttranslational regulatory mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Apolipoprotein A-II is a key regulatory factor of HDL metabolism as appears from studies with transgenic animals and clinical outcomes.

    PubMed

    Maïga, Sira Fatoumata; Kalopissis, Athina-Despina; Chabert, Michèle

    2014-01-01

    The structure and metabolism of HDL are linked to their major apolipoproteins (apo) A-I and A-II. HDL metabolism is very dynamic and depends on the constant remodeling by lipases, lipid transfer proteins and receptors. HDL exert several cardioprotective effects, through their antioxidant and antiinflammatory capacities and through the stimulation of reverse cholesterol transport from extrahepatic tissues to the liver for excretion into bile. HDL also serve as plasma reservoir for C and E apolipoproteins, as transport vehicles for a great variety of proteins, and may have more physiological functions than previously recognized. In this review we will develop several aspects of HDL metabolism with emphasis on the structure/function of apo A-I and apo A-II. An important contribution to our understanding of the respective roles of apo A-I and apo A-II comes from studies using transgenic animal models that highlighted the stabilizatory role of apo A-II on HDL through inhibition of their remodeling by lipases. Clinical studies coupled with proteomic analyses revealed the presence of dysfunctional HDL in patients with cardiovascular disease. Beyond HDL cholesterol, a new notion is the functionality of HDL particles. In spite of abundant literature on HDL metabolic properties, a major question remains unanswered: which HDL particle(s) confer(s) protection against cardiovascular risk?

  19. Mapping Fishing Effort through AIS Data

    PubMed Central

    Natale, Fabrizio; Gibin, Maurizio; Alessandrini, Alfredo; Vespe, Michele; Paulrud, Anton

    2015-01-01

    Several research initiatives have been undertaken to map fishing effort at high spatial resolution using the Vessel Monitoring System (VMS). An alternative to the VMS is represented by the Automatic Identification System (AIS), which in the EU became compulsory in May 2014 for all fishing vessels of length above 15 meters. The aim of this paper is to assess the uptake of the AIS in the EU fishing fleet and the feasibility of producing a map of fishing effort with high spatial and temporal resolution at European scale. After analysing a large AIS dataset for the period January-August 2014 and covering most of the EU waters, we show that AIS was adopted by around 75% of EU fishing vessels above 15 meters of length. Using the Swedish fleet as a case study, we developed a method to identify fishing activity based on the analysis of individual vessels’ speed profiles and produce a high resolution map of fishing effort based on AIS data. The method was validated using detailed logbook data and proved to be sufficiently accurate and computationally efficient to identify fishing grounds and effort in the case of trawlers, which represent the largest portion of the EU fishing fleet above 15 meters of length. Issues still to be addressed before extending the exercise to the entire EU fleet are the assessment of coverage levels of the AIS data for all EU waters and the identification of fishing activity in the case of vessels other than trawlers. PMID:26098430

  20. Status of AIS Frequencies Nationally and Internationally: Improving Satellite Detection of AIS

    DTIC Science & Technology

    2008-09-04

    International Telecommunications Union? • ITU 2007 World Radio Conference – Authorized AIS 1 & AIS 2 as satellite uplink frequencies, on secondary basis...Collision Rate “AIS as is” How do results correlate with predictions? Satellite Detection Statistics with Correlation Processing – ITU -R Rep M.2084 (JSC...Status of AIS Frequencies  Nationally and  Internationally: Improving  satellite  detection of AIS CG‐622 | Joe Hersey Chief, Spectrum Mgt Div USCG

  1. A role for apolipoprotein E, apolipoprotein A-I, and low density lipoprotein receptors in cholesterol transport during regeneration and remyelination of the rat sciatic nerve.

    PubMed Central

    Boyles, J K; Zoellner, C D; Anderson, L J; Kosik, L M; Pitas, R E; Weisgraber, K H; Hui, D Y; Mahley, R W; Gebicke-Haerter, P J; Ignatius, M J

    1989-01-01

    Recent work has demonstrated that apo E secretion and accumulation increase in the regenerating peripheral nerve. The fact that apoE, in conjunction with apoA-I and LDL receptors, participates in a well-established lipid transfer system raised the possibility that apoE is also involved in lipid transport in the injured nerve. In the present study of the crushed rat sciatic nerve, a combination of techniques was used to trace the cellular associations of apoE, apoA-I, and the LDL receptor during nerve repair and to determine the distribution of lipid at each stage. After a crush injury, as axons died and Schwann cells reabsorbed myelin, resident and monocyte-derived macrophages produced large quantities of apoE distal to the injury site. As axons regenerated in the first week, their tips contained a high concentration of LDL receptors. After axon regeneration, apoE and apoA-I began to accumulate distal to the injury site and macrophages became increasingly cholesterol-loaded. As remyelination began in the second and third weeks after injury, Schwann cells exhausted their cholesterol stores, then displayed increased LDL receptors. Depletion of macrophage cholesterol stores followed over the next several weeks. During this stage of regeneration, apoE and apoA-I were present in the extracellular matrix as components of cholesterol-rich lipoproteins. Our results demonstrate that the regenerating peripheral nerve possesses the components of a cholesterol transfer mechanism, and the sequence of events suggests that this mechanism supplies the cholesterol required for rapid membrane biogenesis during axon regeneration and remyelination. Images PMID:2493483

  2. The structure of dimeric apolipoprotein A-IV and its mechanism of self-association.

    PubMed

    Deng, Xiaodi; Morris, Jamie; Dressmen, James; Tubb, Matthew R; Tso, Patrick; Jerome, W Gray; Davidson, W Sean; Thompson, Thomas B

    2012-05-09

    Apolipoproteins are key structural elements of lipoproteins and critical mediators of lipid metabolism. Their detergent-like properties allow them to emulsify lipid or exist in a soluble lipid-free form in various states of self-association. Unfortunately, these traits have hampered high-resolution structural studies needed to understand the biogenesis of cardioprotective high-density lipoproteins (HDLs). We derived a crystal structure of the core domain of human apolipoprotein (apo)A-IV, an HDL component and important mediator of lipid absorption. The structure at 2.4 Å depicts two linearly connected 4-helix bundles participating in a helix swapping arrangement that offers a clear explanation for how the protein self-associates as well as clues to the structure of its monomeric form. This also provides a logical basis for antiparallel arrangements recently described for lipid-containing particles. Furthermore, we propose a "swinging door" model for apoA-IV lipid association.

  3. The Structure of Dimeric Apolipoprotein A-IV and Its Mechanism of Self-Association

    SciTech Connect

    Deng, Xiaodi; Morris, Jamie; Dressmen, James; Tubb, Matthew R.; Tso, Patrick; Jerome, W. Gray; Davidson, W. Sean; Thompson, Thomas B.

    2012-08-10

    Apolipoproteins are key structural elements of lipoproteins and critical mediators of lipid metabolism. Their detergent-like properties allow them to emulsify lipid or exist in a soluble lipid-free form in various states of self-association. Unfortunately, these traits have hampered high-resolution structural studies needed to understand the biogenesis of cardioprotective high-density lipoproteins (HDLs). We derived a crystal structure of the core domain of human apolipoprotein (apo)A-IV, an HDL component and important mediator of lipid absorption. The structure at 2.4 {angstrom} depicts two linearly connected 4-helix bundles participating in a helix swapping arrangement that offers a clear explanation for how the protein self-associates as well as clues to the structure of its monomeric form. This also provides a logical basis for antiparallel arrangements recently described for lipid-containing particles. Furthermore, we propose a 'swinging door' model for apoA-IV lipid association.

  4. Interferon-γ Protects from Staphylococcal Alpha Toxin-Induced Keratinocyte Death through Apolipoprotein L1.

    PubMed

    Brauweiler, Anne M; Goleva, Elena; Leung, Donald Y M

    2016-03-01

    Staphylococcus aureus is a bacterial pathogen that frequently infects the skin, causing lesions and cell destruction through its primary virulence factor, alpha toxin. Here we show that interferon gamma (IFN-?) protects human keratinocytes from cell death induced by staphylococcal alpha toxin. We find that IFN-? prevents alpha toxin binding and reduces expression of the alpha toxin receptor, a disintegrin and metalloproteinase 10 (ADAM10). We determine that the mechanism for IFN-?-mediated resistance to alpha toxin involves the induction of autophagy, a process of cellular adaptation to sublethal damage. We find that IFN-? potently stimulates activation of the primary autophagy effector, light chain 3 (LC3). This process is dependent on upregulation of apolipoprotein L1. Depletion of apolipoprotein L1 by small interfering RNA significantly increases alpha toxin-induced lethality and inhibits activation of light chain 3. We conclude that IFN-? plays a significant role in protecting human keratinocytes from the lethal effects of staphylococcal alpha toxin through apolipoprotein L1-induced autophagy.

  5. Cacao polyphenols influence the regulation of apolipoprotein in HepG2 and Caco2 cells.

    PubMed

    Yasuda, Akiko; Natsume, Midori; Osakabe, Naomi; Kawahata, Keiko; Koga, Jinichiro

    2011-02-23

    Cocoa powder is rich in polyphenols, such as catechins and procyanidins, and has been shown to inhibit low-density lipoprotein (LDL) oxidation and atherogenesis in a variety of models. Human studies have also shown daily intake of cocoa increases plasma high-density lipoprotein (HDL) and decreases LDL levels. However, the mechanisms responsible for these effects of cocoa on cholesterol metabolism have yet to be fully elucidated. The present study investigated the effects of cacao polyphenols on the production of apolipoproteins A1 and B in human hepatoma HepG2 and intestinal Caco2 cell lines. The cultured HepG2 cells or Caco2 cells were incubated for 24 h in the presence of cacao polyphenols such as (-)-epicatechin, (+)-catechin, procyanidin B2, procyanidin C1, and cinnamtannin A2. The concentration of apolipoproteins in the cell culture media was quantified using an enzyme-linked immunoassay, and the mRNA expression was quantified by RT-PCR. Cacao polyphenols increased apolipoprotein A1 protein levels and mRNA expression, even though apolipoprotein B protein and the mRNA expression were slightly decreased in both HepG2 cells and Caco2 cells. In addition, cacao polyphenols increased sterol regulatory element binding proteins (SREBPs) and activated LDL receptors in HepG2 cells. These results suggest that cacao polyphenols may increase the production of mature form SREBPs and LDL receptor activity, thereby increasing ApoA1 and decreasing ApoB levels. These results elucidate a novel mechanism by which HDL cholesterol levels become elevated with daily cocoa intake.

  6. Enhanced AIS receiver design for satellite reception

    NASA Astrophysics Data System (ADS)

    Clazzer, Federico; Lázaro, Francisco; Plass, Simon

    2016-12-01

    The possibility to detect Automatic Identification System (AIS) messages from low earth orbit (LEO) satellites paves the road for a plurality of new and unexplored services. Besides worldwide tracking of vessels, maritime traffic monitoring, analysis of vessel routes employing big data, and oceans monitoring are just few of the fields, where satellite-aided AIS is beneficial. Designed for ship-to-ship communication and collision avoidance, AIS satellite reception performs poorly in regions with a high density of vessels. This calls for the development of advanced satellite AIS receivers able to improve the decoding capabilities. In this context, our contribution focuses on the introduction of a new enhanced AIS receiver design and its performance evaluation. The enhanced receiver makes use of a coherent receiver for the low signal-to-noise ratio (SNR) region, while for medium to high SNRs, a differential Viterbi receiver is used. Additional novelty of our work is in the exploitation of previously decoded packets from one vessel that is still under the LEO reception range, to improve the vessel detection probability. The assessment of the performance against a common receiver is done making the use of a simple and tight model of the medium access (MAC) layer and the multi-packet reception (MPR) matrix for physical layer (PHY) representation. Performance results show the benefits of such enhanced receiver, especially when it is bundled with successive interference cancellation (SIC).

  7. Comparison of AIS 1990 update 98 versus AIS 2005 for describing PMHS injuries in lateral and oblique sled tests.

    PubMed

    Yoganandan, Narayan; Pintar, Frank A; Humm, John R; Stadter, Gregory W; Curry, William H; Brasel, Karen J

    2013-01-01

    This study analyzed skeletal and organ injuries in pure lateral and oblique impacts from 20 intact post mortem human surrogate (PMHS) sled tests at 6.7 m/s. Injuries to the shoulder, thorax, abdomen, pelvis and spine were scored using AIS 1990-1998 update and 2005. The Injury Severity Scores (ISS) were extracted for both loadings from both versions. Mean age, stature, total body mass and body mass index for pure lateral and oblique tests: 58 and 55 years, 1.7 and 1.8 m, 69 and 66 kg, and 24 and 21 kg/m(2). Skeletal injuries (ribs, sternum) occurred in both impacts. However, oblique impacts resulted in more injuries. Pure lateral and oblique impacts ISS: 0 to 16 and 0 to 24, representing a greater potential for injury-related consequences in real-world situations in oblique impacts. Internal organs were more involved in oblique impacts. ISS decreased in AIS 2005, reflecting changes to scoring and drawing attention to potential effects for pre-hospital care/medical aspects. Mean AIS scores for the two load vectors and two AIS coding schemes are included. From automotive crashworthiness perspectives, decreases in injury severities might alter injury risk functions with a shift to lower metrics for the same risk level than current risk estimations. This finding influences dummy-based injury criteria and occupant safety as risk functions are used for countermeasure effectiveness and cost-benefit analyses by regulatory bodies. Increase in organ injuries in oblique loading indicate the importance of this vector as current dummies and injury criteria used in regulations are based on pure lateral impact data.

  8. Comparison of AIS 1990 update 98 versus AIS 2005 for describing PMHS injuries in lateral and oblique sled tests

    PubMed Central

    Yoganandan, Narayan; Pintar, Frank A.; Humm, John R.; Stadter, Gregory W.; Curry, William H.; Brasel, Karen J.

    2013-01-01

    This study analyzed skeletal and organ injuries in pure lateral and oblique impacts from 20 intact post mortem human surrogate (PMHS) sled tests at 6.7 m/s. Injuries to the shoulder, thorax, abdomen, pelvis and spine were scored using AIS 1990–1998 update and 2005. The Injury Severity Scores (ISS) were extracted for both loadings from both versions. Mean age, stature, total body mass and body mass index for pure lateral and oblique tests: 58 and 55 years, 1.7 and 1.8 m, 69 and 66 kg, and 24 and 21 kg/m2. Skeletal injuries (ribs, sternum) occurred in both impacts. However, oblique impacts resulted in more injuries. Pure lateral and oblique impacts ISS: 0 to 16 and 0 to 24, representing a greater potential for injury-related consequences in real-world situations in oblique impacts. Internal organs were more involved in oblique impacts. ISS decreased in AIS 2005, reflecting changes to scoring and drawing attention to potential effects for pre-hospital care/medical aspects. Mean AIS scores for the two load vectors and two AIS coding schemes are included. From automotive crashworthiness perspectives, decreases in injury severities might alter injury risk functions with a shift to lower metrics for the same risk level than current risk estimations. This finding influences dummy-based injury criteria and occupant safety as risk functions are used for countermeasure effectiveness and cost-benefit analyses by regulatory bodies. Increase in organ injuries in oblique loading indicate the importance of this vector as current dummies and injury criteria used in regulations are based on pure lateral impact data. PMID:24406958

  9. Soya phytoestrogens, genistein and daidzein, decrease apolipoprotein B secretion from HepG2 cells through multiple mechanisms.

    PubMed

    Borradaile, Nica M; de Dreu, Linda E; Wilcox, Lisa J; Edwards, Jane Y; Huff, Murray W

    2002-09-01

    Diets containing the soya-derived phytoestrogens, genistein and daidzein, decrease plasma cholesterol in humans and experimental animals. The mechanisms responsible for the hypocholesterolaemic effects of these isoflavones are unknown. The present study was conducted to determine if genistein and daidzein regulate hepatocyte cholesterol metabolism and apolipoprotein (apo) B secretion in cultured human hepatoma (HepG2) cells. ApoB secretion was decreased dose-dependently by up to 63% and 71% by genistein and daidzein (100 microM; P<0.0001) respectively. In contrast, no effect on apoAI secretion was observed. Cellular cholesterol synthesis was inhibited 41% by genistein (100 microM; P<0.005) and 18% by daidzein (100 microM; P<0.05), which was associated with significant increases in 3-hydroxy-3-methylglutaryl-CoA reductase mRNA. Cellular cholesterol esterification was decreased 56% by genistein (100 microM; P<0.04) and 29% by daidzein (100 microM; P<0.04); however, mRNA levels for acyl-CoA:cholesterol acyltransferase (ACAT) 1 and ACAT2 were unaffected. At 100 microM, both isoflavones equally inhibited the activities of both forms of ACAT in cells transfected with either ACAT1 or ACAT2. Genistein (100 microM) and daidzein (100 microM) significantly decreased the activity of microsomal triacylglycerol transfer protein (MTP) by 30% and 24% respectively, and significantly decreased MTP mRNA levels by 35% and 55%. Both isoflavones increased low-density lipoprotein (LDL)-receptor mRNA levels by 3- to 6-fold (100 microM; P<0.03) and significantly increased the binding, uptake and degradation of (125)I-labelled LDL, suggesting that enhanced reuptake of newly secreted apoB-containing lipoproteins contributed to the net decrease in apoB secretion. These results indicate that genistein and daidzein inhibit hepatocyte apoB secretion through several mechanisms, including inhibition of cholesterol synthesis and esterification, inhibition of MTP activity and expression and

  10. Soya phytoestrogens, genistein and daidzein, decrease apolipoprotein B secretion from HepG2 cells through multiple mechanisms.

    PubMed Central

    Borradaile, Nica M; de Dreu, Linda E; Wilcox, Lisa J; Edwards, Jane Y; Huff, Murray W

    2002-01-01

    Diets containing the soya-derived phytoestrogens, genistein and daidzein, decrease plasma cholesterol in humans and experimental animals. The mechanisms responsible for the hypocholesterolaemic effects of these isoflavones are unknown. The present study was conducted to determine if genistein and daidzein regulate hepatocyte cholesterol metabolism and apolipoprotein (apo) B secretion in cultured human hepatoma (HepG2) cells. ApoB secretion was decreased dose-dependently by up to 63% and 71% by genistein and daidzein (100 microM; P<0.0001) respectively. In contrast, no effect on apoAI secretion was observed. Cellular cholesterol synthesis was inhibited 41% by genistein (100 microM; P<0.005) and 18% by daidzein (100 microM; P<0.05), which was associated with significant increases in 3-hydroxy-3-methylglutaryl-CoA reductase mRNA. Cellular cholesterol esterification was decreased 56% by genistein (100 microM; P<0.04) and 29% by daidzein (100 microM; P<0.04); however, mRNA levels for acyl-CoA:cholesterol acyltransferase (ACAT) 1 and ACAT2 were unaffected. At 100 microM, both isoflavones equally inhibited the activities of both forms of ACAT in cells transfected with either ACAT1 or ACAT2. Genistein (100 microM) and daidzein (100 microM) significantly decreased the activity of microsomal triacylglycerol transfer protein (MTP) by 30% and 24% respectively, and significantly decreased MTP mRNA levels by 35% and 55%. Both isoflavones increased low-density lipoprotein (LDL)-receptor mRNA levels by 3- to 6-fold (100 microM; P<0.03) and significantly increased the binding, uptake and degradation of (125)I-labelled LDL, suggesting that enhanced reuptake of newly secreted apoB-containing lipoproteins contributed to the net decrease in apoB secretion. These results indicate that genistein and daidzein inhibit hepatocyte apoB secretion through several mechanisms, including inhibition of cholesterol synthesis and esterification, inhibition of MTP activity and expression and

  11. Role of urea on recombinant Apo A-I stability and its utilization in anion exchange chromatography.

    PubMed

    Angarita, Monica; Arosio, Paolo; Müller-Späth, Thomas; Baur, Daniel; Falkenstein, Roberto; Kuhne, Wolfgang; Morbidelli, Massimo

    2014-08-08

    Apolipoprotein A-I (Apo A-I) is an important lipid-binding protein involved in the transport and metabolism of cholesterol. High protein purity, in particular with respect to endotoxins is required for therapeutic applications. The use of urea during the purification process of recombinant Apo A-I produced in Escherichia coli has been suggested so as to provide high endotoxin clearance. In this work, we show that urea can be used as a sole modifier during the ion exchange chromatographic purification of Apo A-I and we investigate the molecular mechanism of elution by correlating the effect of urea on self-association, conformation and adsorption equilibrium properties of a modified model Apo A-I. In the absence of urea the protein was found to be present as a population of oligomers represented mainly by trimers, hexamers and nonamers. The addition of urea induced oligomer dissociation and protein structure unfolding. We correlated the changes in protein association and conformation with variations of the adsorption equilibrium of the protein on a strong anion exchanger. It was confirmed that the adsorption isotherms, described by a Langmuir model, were dependent on both protein and urea concentrations. Monomers, observed at low urea concentration (0.5M), were characterized by larger binding affinity and adsorption capacity compared to both protein oligomers (0M) and unfolded monomers (2-8M). The reduction of both the binding strength and maximum adsorption capacity at urea concentrations larger than 0.5M explains the ability of urea of inducing elution of the protein from the ion exchange resin. The dissociation of the protein complexes occurring during the elution could likely be the origin of the effective clearance of endotoxins originally trapped inside the oligomers.

  12. Extended-release niacin alters the metabolism of plasma apolipoprotein (apo) A-I- and apoB-containing lipoproteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extended-release niacin effectively lowers plasma TG levels and raises plasma HDL cholesterol levels, but the mechanisms responsible for these effects are unclear. We examined the effects of extended-release niacin (2 g/d) and extended-release niacin (2 g/d) plus lovastatin (40 mg/d), relative to pl...

  13. Activated-Ion ETD (AI-ETD) Improves the Ability of ETD to Identify Peptides in a Complex Mixture

    PubMed Central

    Ledvina, Aaron R.; Beauchene, Nicole A.; McAlister, Graeme C.; Syka, John E. P.; Schwartz, Jae C.; Griep-Raming, Jens; Westphall, Michael S.; Coon, Joshua J.

    2010-01-01

    Using a modified ETD-enabled QLT mass spectrometer, we demonstrate the utility of IR activation concomitant with ETD ion-ion reactions (activated-ion ETD, AI-ETD). Analyzing 12 SCX fractions of a LysC digest of human cells (HS) using ETD, CAD, and AI-ETD, we find that AI-ETD generates 13,405 peptide spectral matches (PSMs) at a 1% false-discovery rate (1% FDR), surpassing both ETD (7,968) and CAD (10,904). We also analyze 12 SCX fractions of a tryptic HS digest and find that ETD produces 6,234 PSMs, AI-ETD 9,130 PSMs, and CAD 15,209 PSMs. Compared to ETcaD, AI-ETD generates ~80% more PSMs for tryptic whole cell lysate and ~50% more PSMs for LysC whole cell lysate. PMID:21062032

  14. Monogenic hypocholesterolaemic lipid disorders and apolipoprotein B metabolism.

    PubMed

    Hooper, Amanda J; van Bockxmeer, Frank M; Burnett, John R

    2005-01-01

    The study of apolipoprotein (apo) B metabolism is central to our understanding of human lipoprotein metabolism. Moreover, the assembly and secretion of apoB-containing lipoproteins is a complex process. Increased plasma concentrations of apoB-containing lipoproteins are an important risk factor for the development of atherosclerotic coronary heart disease. In contrast, decreased levels of, but not the absence of, these apoB-containing lipoproteins is associated with resistance to atherosclerosis and potential long life. The study of inherited monogenic dyslipidaemias has been an effective means to elucidate key metabolic steps and biologically relevant mechanisms. Naturally occurring gene mutations in affected families have been useful in identifying important domains of apoB and microsomal triglyceride transfer protein (MTP) governing the metabolism of apoB-containing lipoproteins. Truncation-causing mutations in the APOB gene cause familial hypobetalipoproteinaemia, whereas mutations in MTP result in abetalipoproteinaemia; both rare conditions are characterised by marked hypocholesterolaemia. The purpose of this review is to examine the role of apoB in lipoprotein metabolism and to explore the key biochemical, clinical, metabolic and genetic features of the monogenic hypocholesterolaemic lipid disorders affecting apoB metabolism.

  15. Glucose Regulates the Expression of the Apolipoprotein A5 Gene

    SciTech Connect

    Fruchart, Jamila; Nowak, Maxime; Helleboid-Chapman, Audrey; Jakel, Heidelinde; Moitrot, Emmanuelle; Rommens, Corinne; Pennacchio, Len A.; Fruchart-Najib, Jamila; Fruchart, Jean-Charles

    2008-04-07

    The apolipoprotein A5 gene (APOA5) is a key player in determining triglyceride concentrations in humans and mice. Since diabetes is often associated with hypertriglyceridemia, this study explores whether APOA5 gene expression is regulated by alteration in glucose homeostasis and the related pathways. D-glucose activates APOA5 gene expression in a time- and dose-dependent manner in hepatocytes, and the glycolytic pathway involved was determined using D-glucose analogs and metabolites. Together, transient transfections, electrophoretic mobility shift assays and chromatin immunoprecipitation assays show that this regulation occurs at the transcriptional level through an increase of USF1/2 binding to an E-box in the APOA5 promoter. We show that this phenomenon is not due to an increase of mRNA or protein expression levels of USF. Using protein phosphatases 1 and 2A inhibitor, we demonstrate that D-glucose regulates APOA5 gene via a dephosphorylation mechanism, thereby resulting in an enhanced USF1/2-promoter binding. Last, subsequent suppressions of USF1/2 and phosphatases mRNA through siRNA gene silencing abolished the regulation. We demonstrate that APOA5 gene is up regulated by D-glucose and USF through phosphatase activation. These findings may provide a new cross talk between glucose and lipid metabolism.

  16. Cerebrovascular effects of apolipoprotein E: implications for Alzheimer disease.

    PubMed

    Zlokovic, Berislav V

    2013-04-01

    Human apolipoprotein E (apoE) has 3 isoforms: apoE2, apoE3, and apoE4. APOE4 is a major genetic risk factor for Alzheimer disease and is associated with dementia in Down syndrome and poor neurological outcome after traumatic brain injury, cerebral hemorrhage, and other neuropathological disorders. While apoE4 can induce neuropathology by participating in various cellular and molecular pathways, herein I review data supporting the hypothesis that apoE4 has direct toxic effects on the cerebrovascular system that in turn can lead to secondary neuronal dysfunction and degeneration as well as accumulation of neurotoxins in brain such as β-amyloid (Aβ) in Alzheimer disease. I review Aβ-independent cerebrovascular effects of apoE, particularly activation of a proinflammatory cyclophilin A-mediated pathway in brain vascular pericytes by apoE4 that has recently been shown to lead to a loss of cerebrovascular integrity and blood-brain barrier breakdown causing neuronal injury. I also review Aβ-dependent cerebrovascular effects of apoE such as faulty Aβ clearance from brain to circulation by apoE4. Finally, I discuss isoform-specific interactions of apoE with low-density lipoprotein receptor-related protein 1 on brain vascular cells (ie, endothelial cells, pericytes), which play an important role in Aβ-independent and Aβ-dependent effects of apoE on cerebral vasculature.

  17. Purification and characterization of BmooAi: a new toxin from Bothrops moojeni snake venom that inhibits platelet aggregation.

    PubMed

    de Queiroz, Mayara Ribeiro; Mamede, Carla Cristine N; de Morais, Nadia Cristina G; Fonseca, Kelly Cortes; de Sousa, Bruna Barbosa; Migliorini, Thaís M; Pereira, Déborah Fernanda C; Stanziola, Leonilda; Calderon, Leonardo A; Simões-Silva, Rodrigo; Soares, Andreimar Martins; de Oliveira, Fábio

    2014-01-01

    In this paper, we describe the purification/characterization of BmooAi, a new toxin from Bothrops moojeni that inhibits platelet aggregation. The purification of BmooAi was carried out through three chromatographic steps (ion-exchange on a DEAE-Sephacel column, molecular exclusion on a Sephadex G-75 column, and reverse-phase HPLC chromatography on a C2/C18 column). BmooAi was homogeneous by SDS-PAGE and shown to be a single-chain protein of 15,000 Da. BmooAi was analysed by MALDI-TOF Spectrometry and revealed two major components with molecular masses 7824.4 and 7409.2 as well as a trace of protein with a molecular mass of 15,237.4 Da. Sequencing of BmooAi by Edman degradation showed two amino acid sequences: IRDFDPLTNAPENTA and ETEEGAEEGTQ, which revealed no homology to any known toxin from snake venom. BmooAi showed a rather specific inhibitory effect on platelet aggregation induced by collagen, adenosine diphosphate, or epinephrine in human platelet-rich plasma in a dose-dependent manner, whereas it had little or no effect on platelet aggregation induced by ristocetin. The effect on platelet aggregation induced by BmooAi remained active even when heated to 100°C. BmooAi could be of medical interest as a new tool for the development of novel therapeutic agents for the prevention and treatment of thrombotic disorders.

  18. Purification and Characterization of BmooAi: A New Toxin from Bothrops moojeni Snake Venom That Inhibits Platelet Aggregation

    PubMed Central

    Ribeiro de Queiroz, Mayara; Mamede, Carla Cristine N.; de Morais, Nadia Cristina G.; Cortes Fonseca, Kelly; Barbosa de Sousa, Bruna; Migliorini, Thaís M.; Pereira, Déborah Fernanda C.; Stanziola, Leonilda; Calderon, Leonardo A.; Simões-Silva, Rodrigo; Martins Soares, Andreimar; de Oliveira, Fábio

    2014-01-01

    In this paper, we describe the purification/characterization of BmooAi, a new toxin from Bothrops moojeni that inhibits platelet aggregation. The purification of BmooAi was carried out through three chromatographic steps (ion-exchange on a DEAE-Sephacel column, molecular exclusion on a Sephadex G-75 column, and reverse-phase HPLC chromatography on a C2/C18 column). BmooAi was homogeneous by SDS-PAGE and shown to be a single-chain protein of 15,000 Da. BmooAi was analysed by MALDI-TOF Spectrometry and revealed two major components with molecular masses 7824.4 and 7409.2 as well as a trace of protein with a molecular mass of 15,237.4 Da. Sequencing of BmooAi by Edman degradation showed two amino acid sequences: IRDFDPLTNAPENTA and ETEEGAEEGTQ, which revealed no homology to any known toxin from snake venom. BmooAi showed a rather specific inhibitory effect on platelet aggregation induced by collagen, adenosine diphosphate, or epinephrine in human platelet-rich plasma in a dose-dependent manner, whereas it had little or no effect on platelet aggregation induced by ristocetin. The effect on platelet aggregation induced by BmooAi remained active even when heated to 100°C. BmooAi could be of medical interest as a new tool for the development of novel therapeutic agents for the prevention and treatment of thrombotic disorders. PMID:24971359

  19. Peroxisome proliferator-activated receptorα agonists differentially regulate inhibitor of DNA binding expression in rodents and human cells.

    PubMed

    González, María Del Carmen; Corton, J Christopher; Acero, Nuria; Muñoz-Mingarro, Dolores; Quirós, Yolanda; Alvarez-Millán, Juan José; Herrera, Emilio; Bocos, Carlos

    2012-01-01

    Inhibitor of DNA binding (Id2) is a helix-loop-helix (HLH) transcription factor that participates in cell differentiation and proliferation. Id2 has been linked to the development of cardiovascular diseases since thiazolidinediones, antidiabetic agents and peroxisome proliferator-activated receptor (PPAR) gamma agonists, have been reported to diminish Id2 expression in human cells. We hypothesized that PPARα activators may also alter Id2 expression. Fenofibrate diminished hepatic Id2 expression in both late pregnant and unmated rats. In 24 hour fasted rats, Id2 expression was decreased under conditions known to activate PPARα. In order to determine whether the fibrate effects were mediated by PPARα, wild-type mice and PPARα-null mice were treated with Wy-14,643 (WY). WY reduced Id2 expression in wild-type mice without an effect in PPARα-null mice. In contrast, fenofibrate induced Id2 expression after 24 hours of treatment in human hepatocarcinoma cells (HepG2). MK-886, a PPARα antagonist, did not block fenofibrate-induced activation of Id2 expression, suggesting a PPARα-independent effect was involved. These findings confirm that Id2 is a gene responsive to PPARα agonists. Like other genes (apolipoprotein A-I, apolipoprotein A-V), the opposite directional transcriptional effect in rodents and a human cell line further emphasizes that PPARα agonists have different effects in rodents and humans.

  20. Peroxisome Proliferator-Activated Receptorα Agonists Differentially Regulate Inhibitor of DNA Binding Expression in Rodents and Human Cells

    PubMed Central

    González, María del Carmen; Corton, J. Christopher; Acero, Nuria; Muñoz-Mingarro, Dolores; Quirós, Yolanda; Álvarez-Millán, Juan José; Herrera, Emilio; Bocos, Carlos

    2012-01-01

    Inhibitor of DNA binding (Id2) is a helix-loop-helix (HLH) transcription factor that participates in cell differentiation and proliferation. Id2 has been linked to the development of cardiovascular diseases since thiazolidinediones, antidiabetic agents and peroxisome proliferator-activated receptor (PPAR) gamma agonists, have been reported to diminish Id2 expression in human cells. We hypothesized that PPARα activators may also alter Id2 expression. Fenofibrate diminished hepatic Id2 expression in both late pregnant and unmated rats. In 24 hour fasted rats, Id2 expression was decreased under conditions known to activate PPARα. In order to determine whether the fibrate effects were mediated by PPARα, wild-type mice and PPARα-null mice were treated with Wy-14,643 (WY). WY reduced Id2 expression in wild-type mice without an effect in PPARα-null mice. In contrast, fenofibrate induced Id2 expression after 24 hours of treatment in human hepatocarcinoma cells (HepG2). MK-886, a PPARα antagonist, did not block fenofibrate-induced activation of Id2 expression, suggesting a PPARα-independent effect was involved. These findings confirm that Id2 is a gene responsive to PPARα agonists. Like other genes (apolipoprotein A-I, apolipoprotein A-V), the opposite directional transcriptional effect in rodents and a human cell line further emphasizes that PPARα agonists have different effects in rodents and humans. PMID:22701468

  1. AI in space: Past, present, and possible futures

    NASA Technical Reports Server (NTRS)

    Rose, Donald D.; Post, Jonathan V.

    1992-01-01

    While artificial intelligence (AI) has become increasingly present in recent space applications, new missions being planned will require even more incorporation of AI techniques. In this paper, we survey some of the progress made to date in implementing such programs, some current directions and issues, and speculate about the future of AI in space scenarios. We also provide examples of how thinkers from the realm of science fiction have envisioned AI's role in various aspects of space exploration.

  2. Why Don't Accounting Students like AIS?

    ERIC Educational Resources Information Center

    Vatanasakdakul, Savanid; Aoun, Chadi

    2011-01-01

    Purpose: The demand for Accounting Information Systems (AIS) knowledge has increased exponentially over the past two decades, but studying AIS has not proved easy for many accounting students. The aim of the study is to understand the challenges accounting students face in studying AIS through investigation of the factors which may be contributing…

  3. The AI Interdisciplinary Context: Single or Multiple Research Bases?

    ERIC Educational Resources Information Center

    Khawam, Yves J.

    1992-01-01

    This study used citation analysis to determine whether the disciplines contributing to the journal literature of artificial intelligence (AI)--philosophy, psychology, linguistics, computer science, and engineering--share a common AI research base. The idea that AI consists of a completely interdisciplinary endeavor was refuted. (MES)

  4. 47 CFR 80.393 - Frequencies for AIS stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies for AIS stations. 80.393 Section 80.393 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Frequencies Ais Stations § 80.393 Frequencies for AIS stations....

  5. Tactical AI in Real Time Strategy Games

    DTIC Science & Technology

    2015-03-26

    evolutionary algorithms (MOEAs) in this tactical decision making problem allows an AI agent to make fast , effective solutions that do not require modification...ranged attacks. The terran army operates most similarly to Warcraft. The player must still balance food (supply depots), and two other resources (minerals...types of methods analyze the current status of enemy units and makes a decision based on a single metric. These techniques are very fast , but are open to

  6. SDI satellite autonomy using AI and Ada

    NASA Technical Reports Server (NTRS)

    Fiala, Harvey E.

    1990-01-01

    The use of Artificial Intelligence (AI) and the programming language Ada to help a satellite recover from selected failures that could lead to mission failure are described. An unmanned satellite will have a separate AI subsystem running in parallel with the normal satellite subsystems. A satellite monitoring subsystem (SMS), under the control of a blackboard system, will continuously monitor selected satellite subsystems to become alert to any actual or potential problems. In the case of loss of communications with the earth or the home base, the satellite will go into a survival mode to reestablish communications with the earth. The use of an AI subsystem in this manner would have avoided the tragic loss of the two recent Soviet probes that were sent to investigate the planet Mars and its moons. The blackboard system works in conjunction with an SMS and a reconfiguration control subsystem (RCS). It can be shown to be an effective way for one central control subsystem to monitor and coordinate the activities and loads of many interacting subsystems that may or may not contain redundant and/or fault-tolerant elements. The blackboard system will be coded in Ada using tools such as the ABLE development system and the Ada Production system.

  7. Apolipoprotein CII from rainbow trout (Oncorhynchus mykiss) is functionally active but structurally very different from mammalian apolipoprotein CII.

    PubMed

    Shen, Y; Lindberg, A; Olivecrona, G

    2000-08-22

    Apolipoprotein CII (apoCII) plays an important role in plasma lipid metabolism as an activator for lipoprotein lipase (LPL). We have amplified and sequenced apoCII cDNA from rainbow trout. Amino acid sequence analyses confirmed that this sequence corresponded to the protein that had apoCII activity. Northern blot analyses showed that apoCII mRNA was present in both liver and intestine, but the level in intestine was very low. Two major transcripts (800 and 600bp) were found. The predicted amino acid sequence consists of 112 amino acid residues, including the signal peptide. The mature peptide is seven residues longer than human apoCII (86 versus 79 residues) due to an extension at the amino-terminal end. The rainbow trout sequence showed an overall identity of only 20-25% to previously known apoCII sequences. The carboxy-terminal region (residues 51-79, human numbering) showed 35-45% identity to other apoCII sequences, while in the amino-terminal region, there was little if any identity and it was not possible to predict any long amphipathic, potentially lipid-binding alpha-helices. Trout apoCII was present in all lipoprotein fractions including LDL. At +10 degrees C trout plasma showed higher ability to stimulate LPL than human plasma. We conclude that apoCII from rainbow trout is in most parts structurally different from apoCII from other species, and that it is adapted to function at low temperature.

  8. Targeted Proteomics Identifies Paraoxonase/Arylesterase 1 (PON1) and Apolipoprotein Cs as Potential Risk Factors for Hypoalphalipoproteinemia in Diabetic Subjects Treated with Fenofibrate and Rosiglitazone.

    PubMed

    Ronsein, Graziella E; Reyes-Soffer, Gissette; He, Yi; Oda, Michael; Ginsberg, Henry; Heinecke, Jay W

    2016-03-01

    Low levels of high-density lipoprotein cholesterol (HDL-C) and high triglyceride levels contribute to the excess rate of cardiovascular events seen in subjects with type 2 diabetes. Fenofibrate treatment partially reverses dyslipidemia in these subjects. However, a paradoxical marked reduction in HDL-C and HDL's major protein, apolipoprotein A-I, is a complication of fenofibrate in combination with rosiglitazone, an insulin-sensitizing agent. Risk factors for this condition, termed hypoalphalipoproteinemia, have yet to be identified. Using a case-control study design with subjects enrolled in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, we tested the hypothesis that alterations in HDL's protein cargo predispose diabetic subjects to fenofibrate/rosiglitazone-induced hypoalphalipoproteinemia. HDL was isolated from blood obtained from controls (no decreases or increase in HDL-C while receiving fenofibrate/rosiglitazone therapy) and cases (developed hypoalphalipoproteinemia after fenofibrate/rosiglitazone treatment) participating in the ACCORD study before they began fenofibrate/rosiglitazone treatment. HDL proteins were quantified by targeted parallel reaction monitoring (PRM) and selected reaction monitoring (SRM) with isotope dilution. This approach demonstrated marked increases in the relative concentrations of paraoxonase/arylesterase 1 (PON1), apolipoprotein C-II (APOC2), apolipoprotein C-I, and apolipoprotein H in the HDL of subjects who developed hypoalphalipoproteinemia. The case and control subjects did not differ significantly in baseline HDL-C levels or other traditional lipid risk factors. We used orthogonal biochemical techniques to confirm increased levels of PON1 and APOC2. Our observations suggest that an imbalance in HDL proteins predisposes diabetic subjects to develop hypoalphalipoproteinemia on fenofibrate/rosiglitazone therapy.

  9. Kinetics of lipids, apolipoproteins, and cholesteryl ester transfer protein in plasma after a bicycle marathon.

    PubMed

    Föger, B; Wohlfarter, T; Ritsch, A; Lechleitner, M; Miller, C H; Dienstl, A; Patsch, J R

    1994-05-01

    The short-term effects of prolonged intense exercise on plasma lipid transport parameters including cholesterol, triglycerides (TGs), low-density lipoprotein (LD) cholesterol, high-density lipoprotein (HDL) cholesterol, and its subfractions HDL2 cholesterol and HDL3 cholesterol, on apolipoproteins (apos) A-I, A-II, and B, and on mass and activity of cholesteryl ester transfer protein (CETP) were studied in eight male endurance-trained athletes over the first week after a bicycle marathon. CETP mass concentration in plasma was quantified by a newly developed immunoradiometric assay (IRMA). Plasma concentrations of cholesterol, TGs, LDL cholesterol, apo B, CETP, and cholesteryl ester transfer activity (CETA) were significantly reduced in the recovery period compared with pre-exercise values (cholesterol by 20%, P < .05; TGs by 63%, P < .05; LDL cholesterol by 32%, P < .05; apo B by 18%, P < .05; CETP mass by 29%, P < .05; and CETA by 14%, P < .05). HDL cholesterol and HDL2 cholesterol, in contrast, were significantly increased in the post-exercise period (HDL cholesterol by 12%, P < .05, and HDL2 cholesterol by 96%, P < .05), whereas HDL3 cholesterol showed a tendency to decrease in the late recovery period (by 8%, NS). Although changes in cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, apo B, and CETP mass and activity were already evident in the early recovery period, HDL2 cholesterol showed a delayed response, reaching its maximum 72 hours after initiation of exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. RISK and SAFE Signaling Pathway Involvement in Apolipoprotein A-I-Induced Cardioprotection

    PubMed Central

    Kalakech, Hussein; Hibert, Pierre; Prunier-Mirebeau, Delphine; Tamareille, Sophie; Letournel, Franck; Macchi, Laurent; Pinet, Florence; Furber, Alain; Prunier, Fabrice

    2014-01-01

    Recent findings indicate that apolipoprotein A-I (ApoA-I) may be a protective humoral mediator involved in remote ischemic preconditioning (RIPC). This study sought to determine if ApoA-I mediates its protective effects via the RISK and SAFE signaling pathways implicated in RIPC. Wistar rats were allocated to one of the following groups. Control: rats were subjected to myocardial ischemia/reperfusion (I/R) without any further intervention; RIPC: four cycles of limb I/R were applied prior to myocardial ischemia; ApoA-I: 10 mg/Kg of ApoA-I were intravenously injected prior to myocardial ischemia; ApoA-I + inhibitor: pharmacological inhibitors of RISK/SAFE pro-survival kinase (Akt, ERK1/2 and STAT-3) were administered prior to ApoA-I injection. Infarct size was significantly reduced in the RIPC group compared to Control. Similarly, ApoA-I injection efficiently protected the heart, recapitulating RIPC-induced cardioprotection. The ApoA-I protective effect was associated with Akt and GSK-3β phosphorylation and substantially inhibited by pretreatment with Akt and ERK1/2 inhibitors. Pretreatment with ApoA-I in a rat model of I/R recapitulates RIPC-induced cardioprotection and shares some similar molecular mechanisms with those of RIPC-involved protection of the heart. PMID:25237809

  11. Charge-transfer interactions induce surface dependent conformational changes in apolipoprotein biocorona.

    PubMed

    Raghavendra, Achyut J; Alsaleh, Nasser; Brown, Jared M; Podila, Ramakrishna

    2017-03-07

    Upon introduction into a biological system, engineered nanomaterials (ENMs) rapidly associate with a variety of biomolecules such as proteins and lipids to form a biocorona. The presence of "biocorona" influences nano-bio interactions considerably, and could ultimately result in altered biological responses. Apolipoprotein A-I (ApoA-I), the major constituent of high-density lipoprotein (HDL), is one of the most prevalent proteins found in ENM-biocorona irrespective of ENM nature, size, and shape. Given the importance of ApoA-I in HDL and cholesterol transport, it is necessary to understand the mechanisms of ApoA-I adsorption and the associated structural changes for assessing consequences of ENM exposure. Here, the authors used a comprehensive array of microscopic and spectroscopic tools to elucidate the interactions between ApoA-I and 100 nm Ag nanoparticles (AgNPs) with four different surface functional groups. The authors found that the protein adsorption and secondary structural changes are highly dependent on the surface functionality. Our electrochemical studies provided new evidence for charge transfer interactions that influence ApoA-I unfolding. While the unfolding of ApoA-I on AgNPs did not significantly change their uptake and short-term cytotoxicity, the authors observed that it strongly altered the ability of only some AgNPs to generate of reactive oxygen species. Our results shed new light on the importance of surface functionality and charge transfer interactions in biocorona formation.

  12. Apolipoprotein E: Risk factor for Alzheimer disease

    SciTech Connect

    Tsai, M.S.; Thibodeau, S.N.; Tangalos, E.G.; Petersen, R.C.; Kokmen, E.; Smith, G.E.; Schaid, D.J.; Ivnik, R.J. )

    1994-04-01

    The apolipoprotein E gene (APOE) has three common alleles (E2, E3, and E4) that determine six genotypes in the general population. In this study, the authors examined 77 patients with late-onset Alzheimer disease (AD), along with an equal number of age- and sex-matched controls, for an association with the APOE-E4 allele. They show that the frequency of this allele among AD patients was significantly higher than that among the control population (.351 vs. .130, P = .000006). The genotype frequencies also differed between the two groups (P = .0002), with the APOE-E4/E3 genotype being the most common in the AD group and the APOE-E3/E3 being the most common in the control group. In the AD group, homozygosity for E4 was found in nine individuals, whereas none was found in the control group. The odds ratio for AD, when associated with one or two E4 alleles, was 4.6 (95% confidence interval [CI] 1.9-12.3), while the odds ratio for AD, when associated with heterozygosity for APOE-E4, was 3.6 (05% CI 1.5-9.8). Finally, the median age at onset among the AD patients decreased from 83 to 78 to 74 years as the number of APOE-E4 alleles increased from 0 to 1 to 2, respectively (test for trend, P = .001). The data, which are in agreement with recent reports, suggest that the APOE-E4 allele is associated with AD and that this allelic variant may be an important risk factor for susceptibility to AD in the general population. 30 refs., 5 tabs.

  13. Apolipoprotein A5, a crucial determinant of plasma triglyceridelevels, is highlyresponsive to PPARalpha activators

    SciTech Connect

    Vu-Dac, Ngoc; Gervois, Philippe; Jakel, Heidi; Nowak, Maxine; Bauge, Eric; Dehondt, Helene; Staels, Bart; Pennacchio, Len A.; Fruchart-Najib, Jamila; Fruchart, Jean-Charles

    2003-03-30

    The recently discovered APOA5 gene has been shown in humans and mice to be important in determining plasma triglycerides (TG) levels, a major cardiovascular disease risk factor. APOAV represents the first described apolipoprotein where over-expression lowers triglyceride levels. Since fibrates represent a commonly used therapy for lowering plasma triglycerides in humans, we investigated their ability to modulate APOA5 gene expression and consequently influence plasma TG levels. Human primary hepatocytes treated with Wy 14,643 or fenofibrate displayed a strong induction of APOA5 mRNA. Deletion and mutagenesis analyses of the proximal APOA5 promoter firmly demonstrate the presence of a functional PPAR response element. These findings demonstrate that APOA5 is a highly responsive PPARa target gene and support its role as a major mediator for how fibrates reduce plasma triglycerides in humans.

  14. Beef in an Optimal Lean Diet study: effects on lipids, lipoproteins, and apolipoproteins123

    PubMed Central

    Roussell, Michael A; Hill, Alison M; Gaugler, Trent L; West, Sheila G; Vanden Heuvel, John P; Alaupovic, Petar; Gillies, Peter J

    2012-01-01

    Background: A Step I diet with lean beef compared with lean white meat both decrease LDL cholesterol. To our knowledge, no studies have evaluated a low–saturated fatty acid (SFA) (<7% calories) diet that contains lean beef. Objective: We studied the effect on LDL cholesterol of cholesterol-lowering diets with varying amounts of lean beef [ie, Dietary Approaches to Stop Hypertension (DASH): 28 g beef/d; Beef in an Optimal Lean Diet (BOLD): 113 g beef/d; and Beef in an Optimal Lean Diet plus additional protein (BOLD+): 153 g beef/d] compared with that of a healthy American diet (HAD). Design: Thirty-six hypercholesterolemic participants (with LDL-cholesterol concentrations >2.8 mmol/L) were randomly assigned to consume each of the 4 diets (HAD: 33% total fat, 12% SFA, 17% protein, and 20 g beef/d), DASH (27% total fat, 6% SFA, 18% protein, and 28 g beef/d), BOLD (28% total fat, 6% SFA, 19% protein, and 113 g beef/d), and BOLD+ (28% total fat, 6% SFA, 27% protein, and 153 g beef/d) for 5 wk. Results: There was a decrease in total cholesterol (TC) and LDL-cholesterol concentrations (P < 0.05) after consumption of the DASH (−0.49 ± 0.11 and −0.37 ± 0.09 mmol/L, respectively), BOLD (−0.48 ± 0.10 and −0.35 ± 0.9 mmol/L, respectively), and BOLD+ (−0.50 ± 0.10 and −0.345 ± 0.09 mmol/L, respectively) diets compared with after consumption of the HAD (−0.22 ± 0.10 and −0.14 ± 0.10 mmol/L, respectively). Apolipoprotein A-I, C-III, and C-III bound to apolipoprotein A1 particles decreased after BOLD and BOLD+ diets compared with after the HAD, and there was a greater decrease in apolipoprotein B after consumption of the BOLD+ diet than after consumption of the HAD (P < 0.05 for both). LDL cholesterol and TC decreased after consumption of the DASH, BOLD, and BOLD+ diets when the baseline C-reactive protein (CRP) concentration was <1 mg/L; LDL cholesterol and TC decreased when baseline CRP concentration was >1 mg/L with the BOLD and BOLD+ diets

  15. Tel Aviv-Heidelberg three-generation offspring study: Genetic determinants of apolipoprotein A1 and apolipoprotein B

    SciTech Connect

    Livshits, G.; Graff, E.; Brunner, D.

    1995-07-03

    The contribution of major gene and multifactorial effects on variation of plasma apolipoproteins A1 and B has been tested in a large sample of population-based Israeli pedigrees. Our most parsimonious and best fitting model for both apolipoproteins is consistent with Mendelian transmissibility, with significant contribution of major genes (with 2 alleles recessive and dominant within each locus) and polygenes, but neglects effects of common sib environment as well as related intergeneration differences in polygenic effects. Total genetic effects explain 71 and 58% of phenotypic variance of APO-A1 and APO-B levels. The major genes account for about 44 and 32% of the variance in APO-A1 and APO-B, respectively, and the frequency of the recessive alleles determining the high level of apolipoproteins under the study in the Israeli population is in the vicinity of 40% at each locus. 27 refs, 1 fig., 4 tabs.

  16. Expression and prognostic significance of apolipoprotein D in breast cancer.

    PubMed Central

    Díez-Itza, I.; Vizoso, F.; Merino, A. M.; Sánchez, L. M.; Tolivia, J.; Fernández, J.; Ruibal, A.; López-Otín, C.

    1994-01-01

    Apolipoprotein D (apo D) is a glycoprotein involved in the human plasma lipid transport system and present at large amounts in cyst fluid from women with gross cystic disease of the breast. Apo D expression in breast carcinomas was examined by immunoperoxidase staining of a series of 163 tumors. A total of 60 (36.8%) tumors were negative for apo D immunostaining, 28 (17.2%) carcinomas were weakly positive, 33 (20.2%) were moderately stained, whereas the remaining 42 (25.8%) tumors were strongly stained with the specific antibodies. No significant correlation was found between apo D content and tumor size, lymph node involvement, or biochemical parameters such as estrogen receptors, cathepsin D, or pS2 protein. However, the finding of a significant association between apo D and menopausal status of patients or differentiation grade of tumors, with apo D values being lower in tumors from premenopausal women or in poorly differentiated carcinomas, suggested a potential value of this glycoprotein as a prognostic factor in breast cancer. Preliminary analysis of relapse-free survival and overall survival in a subgroup of 152 women with a mean follow-up of 42 months confirmed that low apo D values were significantly associated to a shorter relapse-free survival and poorer survival. According to these data, we propose that apo D in combination with other well-established prognostic factors may contribute to more accurately identify subgroups of breast cancer patients with low or high risk for relapse and death. Images Figure 1 Figure 2 Figure 3 PMID:8311115

  17. Cerebral lipid deposition in aged apolipoprotein-E-deficient mice.

    PubMed Central

    Walker, L. C.; Parker, C. A.; Lipinski, W. J.; Callahan, M. J.; Carroll, R. T.; Gandy, S. E.; Smith, J. D.; Jucker, M.; Bisgaier, C. L.

    1997-01-01

    To assess the influence of age and diet on cerebral pathology in mice lacking apolipoprotein E (apoE), four male apoE knockout mice (epsilon -/-), and five male wild-type (epsilon +/+) littermate controls were placed on a high-fat/high-cholesterol diet for 7 weeks beginning at 17 months of age. All four aged knockout mice developed xanthomatous lesions in the brain consisting mostly of crystalline cholesterol clefts, lipid globules, and foam cells. Smaller xanthomas were confined mainly to the choroid plexus and ventral fornix in the roof of the third ventricle, occasionally extending subpially along the choroidal fissure and into the adjacent parenchyma. More advanced xanthomas disrupted adjoining neural tissue in the fornix, hippocampus, and dorsal diencephalon; in one case, over 60% of one telencephalic hemisphere, including nearly the entire neocortex, was obliterated by the lesion. No xanthomas were observed in aged wild-type controls fed the high-fat/high-cholesterol diet. Brains from 42 additional animals, fed only conventional chow, were examined; 3 of 15 aged (15- to 23-month-old) apoE knockout mice developed small choroidal xanthomas. In contrast, no lesions were observed in five young (2- to 4-month-old) apoE knockout mice or in any wild-type controls between the ages of 2 and 23 months. Our findings indicate that disorders of lipid metabolism can induce significant pathological changes in the central nervous system of aged apoE knockout mice, particularly those on a high-fat/high-cholesterol diet. It may be fruitful to seek potential interactions between genetic factors and diet in modulating the risk of Alzheimer's disease and other neurodegenerative disorders in aged humans. Images Figure 1 Figure 2 PMID:9358763

  18. Covalent structure of apolipoprotein A-II from Macaca mulatta serum high-density lipoproteins.

    PubMed

    Edelstein, C; Noyes, C; Keim, P; Heinrikson, R L; Fellows, R E; Scanu, A M

    1976-03-23

    The covalent structure of apolipoprotein A-II, isolated from the serum high-density lipoprotein of a single male Rhesus monkey (Macaca mulatta), was determined. The amino acid sequence of this 77-residue polypeptide is: less than Glu-Ala-Glu-Glu-Pro5-Ser-Val-Glu-Ser-Leu10-Val-Ser-Gln-Tyr-Phe15-Gln-Thr-Val-Thr-Asp20-Tyr-Gly-Lys-Asp-Leu25-Met-Glu-Lys-Val-Lys30-Ser-Pro-Glu-Leu-Gln35-Ala-Gln-Ala-Lys-Ala40-Tyr-Phe-Glu-Lys-Ser45-Lys-Glu-Gln-Leu-Thr50-Pro-Leu-Val-Lys-Lys55-Ala-Gly-Thr-Asp-Leu60-Val-Asn-Phe-Leu-Ser65-Tyr-Phe-Val-Glu-Leu70-Arg-Thr-Gln-Pro-Ala75-Thr-Gln-COOH. A comparison of this structure to that of the monomeric form of human apolipoprotein A-II reveals a high degree of homology except for six conservative amino acid replacements (positions 3, 6, 40, 53, 59, and 71). Of particular structural significance is the replacement of cysteine by serine in position 6. This explaines why Rhesus A-II exists in monomeric form, contrary to the established dimeric nature of the human protein.

  19. Solid lipid nanoparticles as a vehicle for brain-targeted drug delivery: two new strategies of functionalization with apolipoprotein E

    NASA Astrophysics Data System (ADS)

    Rute Neves, Ana; Fontes Queiroz, Joana; Weksler, Babette; Romero, Ignacio A.; Couraud, Pierre-Olivier; Reis, Salette

    2015-12-01

    Nanotechnology can be an important tool to improve the permeability of some drugs for the blood-brain barrier. In this work we created a new system to enter the brain by functionalizing solid lipid nanoparticles with apolipoprotein E, aiming to enhance their binding to low-density lipoprotein receptors on the blood-brain barrier endothelial cells. Solid lipid nanoparticles were successfully functionalized with apolipoprotein E using two distinct strategies that took advantage of the strong interaction between biotin and avidin. Transmission electron microscopy images revealed spherical nanoparticles, and dynamic light scattering gave a Z-average under 200 nm, a polydispersity index below 0.2, and a zeta potential between -10 mV and -15 mV. The functionalization of solid lipid nanoparticles with apolipoprotein E was demonstrated by infrared spectroscopy and fluorimetric assays. In vitro cytotoxic effects were evaluated by MTT and LDH assays in the human cerebral microvascular endothelial cells (hCMEC/D3) cell line, a human blood-brain barrier model, and revealed no toxicity up to 1.5 mg ml-1 over 4 h of incubation. The brain permeability was evaluated in transwell devices with hCMEC/D3 monolayers, and a 1.5-fold increment in barrier transit was verified for functionalized nanoparticles when compared with non-functionalized ones. The results suggested that these novel apolipoprotein E-functionalized nanoparticles resulted in dynamic stable systems capable of being used for an improved and specialized brain delivery of drugs through the blood-brain barrier.

  20. AIS spectra of desert shrub canopies

    NASA Technical Reports Server (NTRS)

    Murray, R.; Isaacson, D. L.; Schrumpf, B. J.; Ripple, W. J.; Lewis, A. J.

    1986-01-01

    Airborne Imaging Spectrometer (AIS) data were collected 30 August 1985 from a desert shrub community in central Oregon. Spectra from artificial targets placed on the test site and from bare soil, big sagebrush (Artemesia tridentata wyomingensis), silver sagebrush (Artemesia cana bolander), and exposed volcanic rocks were studied. Spectral data from grating position 3 (tree mode) were selected from 25 ground positions for analysis by Principal Factor Analysis (PFA). In this grating position, as many as six factors were identified as significant in contributing to spectral structure. Channels 74 through 84 (tree mode) best characterized between-class differences. Other channels were identified as nondiscriminating and as associated with such errors as excessive atmospheric absorption and grating positin changes. The test site was relatively simple with the two species (A. tridentata and A. cana) representing nearly 95% of biomass and with only two mineral backgrounds, a montmorillonitic soil and volcanic rocks. If, as in this study, six factors of spectral structure can be extracted from a single grating position from data acquired over a simple vegetation community, then AIS data must be considered rich in information-gathering potential.

  1. AI techniques in geomagnetic storm forecasting

    NASA Astrophysics Data System (ADS)

    Lundstedt, Henrik

    This review deals with how geomagnetic storms can be predicted with the use of Artificial Intelligence (AI) techniques. Today many different Al techniques have been developed, such as symbolic systems (expert and fuzzy systems) and connectionism systems (neural networks). Even integrations of AI techniques exist, so called Intelligent Hybrid Systems (IHS). These systems are capable of learning the mathematical functions underlying the operation of non-linear dynamic systems and also to explain the knowledge they have learned. Very few such powerful systems exist at present. Two such examples are the Magnetospheric Specification Forecast Model of Rice University and the Lund Space Weather Model of Lund University. Various attempts to predict geomagnetic storms on long to short-term are reviewed in this article. Predictions of a month to days ahead most often use solar data as input. The first SOHO data are now available. Due to the high temporal and spatial resolution new solar physics have been revealed. These SOHO data might lead to a breakthrough in these predictions. Predictions hours ahead and shorter rely on real-time solar wind data. WIND gives us real-time data for only part of the day. However, with the launch of the ACE spacecraft in 1997, real-time data during 24 hours will be available. That might lead to the second breakthrough for predictions of geomagnetic storms.

  2. Hot spots in apolipoprotein A-II misfolding and amyloidosis in mice and men

    PubMed Central

    Gursky, Olga

    2014-01-01

    ApoA-II is the second-major protein of high-density lipoproteins. C-terminal extension in human apoA-II or point substitutions in murine apoA-II cause amyloidosis. The molecular mechanism of apolipoprotein misfolding, from the native predominantly α-helical conformation to cross-β-sheet in amyloid, is unknown. We used 12 sequence-based prediction algorithms to identify two ten-residue segments in apoA-II that probably initiate β-aggregation. Previous studies of apoA-II fragments experimentally verify this prediction. Together, experimental and bioinformatics studies explain why the C-terminal extension in human apoA-II causes amyloidosis and why, unlike murine apoA-II, human apoA-II normally does not cause amyloidosis despite its unusually high sequence propensity for β-aggregation. PMID:24561203

  3. Signal transduction pathways provide opportunities to enhance HDL and apoAI-dependent reverse cholesterol transport.

    PubMed

    Mulay, Vishwaroop; Wood, Peta; Rentero, Carles; Enrich, Carlos; Grewal, Thomas

    2012-02-01

    Binding of High Density Lipoprotein (HDL) and its major apolipoprotein A-I (apoA-I) to cell surface receptors is believed to initiate a plethora of signaling cascades that promote atheroprotective cell behavior, including the removal of excess cholesterol from lipid-loaded macrophages. More specifically, HDL and apoA-I binding to scavenger receptor BI (SR-BI) and ATP-binding cassette (ABC) transporter A1 has been shown to activate protein kinase A and C (PKA, PKC), Rac/Rho GTPases, Janus Kinase 2 (JAK2), calmodulin as well as mitogen-activated protein kinases (MAPK). Some of these signaling events upregulate mobilization of cholesterol from cellular pools, while others promote efflux pathways through increased expression, stability, and cell surface localization of SR-BI and ABCA1. This review aims to summarize the current knowledge of HDL- and apoA-I -induced signal transduction pathways that are linked to cholesterol efflux and discusses the underlying mechanisms that could couple ligand binding to SR-BI and ABCA1 with signaling and cholesterol export. Additional focus is given on the potential of pharmacological intervention to modulate the activity of signaling cascades for the inhibition or regression of cholesterol accumulation in atherosclerotic lesions.

  4. The implementation of AI technologies in computer wargames

    NASA Astrophysics Data System (ADS)

    Tiller, John A.

    2004-08-01

    Computer wargames involve the most in-depth analysis of general game theory. The enumerated turns of a game like chess are dwarfed by the exponentially larger possibilities of even a simple computer wargame. Implementing challenging AI is computer wargames is an important goal in both the commercial and military environments. In the commercial marketplace, customers demand a challenging AI opponent when they play a computer wargame and are frustrated by a lack of competence on the part of the AI. In the military environment, challenging AI opponents are important for several reasons. A challenging AI opponent will force the military professional to avoid routine or set-piece approaches to situations and cause them to think much deeper about military situations before taking action. A good AI opponent would also include national characteristics of the opponent being simulated, thus providing the military professional with even more of a challenge in planning and approach. Implementing current AI technologies in computer wargames is a technological challenge. The goal is to join the needs of AI in computer wargames with the solutions of current AI technologies. This talk will address several of those issues, possible solutions, and currently unsolved problems.

  5. Quantifying the tracking capability of space-based AIS systems

    NASA Astrophysics Data System (ADS)

    Skauen, Andreas Nordmo

    2016-01-01

    The Norwegian Defence Research Establishment (FFI) has operated three Automatic Identification System (AIS) receivers in space. Two are on dedicated nano-satellites, AISSat-1 and AISSat-2. The third, the NORAIS Receiver, was installed on the International Space Station. A general method for calculating the upper bound on the tracking capability of a space-based AIS system has been developed and the results from the algorithm applied to AISSat-1 and the NORAIS Receiver individually. In addition, a constellation of AISSat-1 and AISSat-2 is presented. The tracking capability is defined as the probability of re-detecting ships as they move around the globe and is explained to represent and upper bound on a space-based AIS system performance. AISSat-1 and AISSat-2 operates on the nominal AIS1 and AIS2 channels, while the NORAIS Receiver data used are from operations on the dedicated space AIS channels, AIS3 and AIS4. The improved tracking capability of operations on the space AIS channels is presented.

  6. Phospholipid transfer protein in human plasma associates with proteins linked to immunity and inflammation.

    PubMed

    Cheung, Marian C; Vaisar, Tomás; Han, Xianlin; Heinecke, Jay W; Albers, John J

    2010-08-31

    Phospholipid transfer protein (PLTP), which associates with apolipoprotein A-I (the major HDL protein), plays a key role in lipoprotein remodeling. Because its level in plasma increases during acute inflammation, it may also play previously unsuspected roles in the innate immune system. To gain further insight into its potential physiological functions, we isolated complexes containing PLTP from plasma by immunoaffinity chromatography and determined their composition. Shotgun proteomics revealed that only 6 of the 24 proteins detected in the complexes were apolipoproteins. The most abundant proteins were clusterin (apoJ), PLTP itself, coagulation factors, complement factors, and apoA-I. Remarkably, 20 of the 24 proteins had known protein-protein interactions. Biochemical studies confirmed two previously established interactions and identified five new ones between PLTP and proteins. Moreover, clusterin, apoA-I, and apoE preserved the lipid-transfer activity of recombinant PLTP in the absence of lipid, indicating that these interactions may have functional significance. Unexpectedly, lipids accounted for only 3% of the mass of the PLTP complexes. Collectively, our observations indicate that PLTP in human plasma resides on lipid-poor complexes dominated by clusterin and proteins implicated in host defense and inflammation. They further suggest that protein-protein interactions drive the formation of PLTP complexes in plasma.

  7. Cystatin C deficiency increases elastic lamina degradation and aortic dilatation in apolipoprotein E-null mice.

    PubMed

    Sukhova, Galina K; Wang, Bing; Libby, Peter; Pan, Jie-Hong; Zhang, Yaou; Grubb, Anders; Fang, Kenneth; Chapman, Harold A; Shi, Guo-Ping

    2005-02-18

    The pathogenesis of atherosclerosis and abdominal aortic aneurysm involves substantial proteolysis of the arterial extracellular matrix. The lysosomal cysteine proteases can exert potent elastolytic and collagenolytic activity. Human atherosclerotic plaques have increased cysteine protease content and decreased levels of the endogenous inhibitor cystatin C, suggesting an imbalance that would favor matrix degradation in the arterial wall. This study tested directly the hypothesis that impaired expression of cystatin C alters arterial structure. Cystatin C-deficient mice (Cyst C-/-) were crossbred with apolipoprotein E-deficient mice (ApoE-/-) to generate cystatin C and apolipoprotein E-double deficient mice (Cyst C-/-ApoE-/-). After 12 weeks on an atherogenic diet, cystatin C deficiency yielded significantly increased tunica media elastic lamina fragmentation, decreased medial size, and increased smooth muscle cell and collagen content in aortic lesions of ApoE-/- mice. Cyst C-/-ApoE-/- mice also showed dilated thoracic and abdominal aortae compared with control ApoE-/- mice, although atheroma lesion size, intimal macrophage accumulation, and lipid core size did not differ between these mice. These findings demonstrate directly the importance of cysteine protease/protease inhibitor balance in dysregulated arterial integrity and remodeling during experimental atherogenesis.

  8. Suppressive effects of cacao polyphenols on the development of atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Natsume, Midori; Baba, Seigo

    2014-01-01

    Previous studies in humans have shown that the cacao polyphenols, (-)-epicatechin and its oligomers, prevent in vitro and ex vivo low-density lipoprotein oxidation mediated by free radical generators and metal ions and also reduce plasma LDL-cholesterol levels. The aim of this study was to examine the effects of cacao polyphenols on the development of atherosclerosis in apolipoprotein E-deficient (-/-) mice. Mice aged 8 weeks (n = 90) were randomized into three groups, and fed either normal mouse chow (controls) or chow supplemented with 0.25 or 0.40 % cacao polyphenols for 16 weeks. The mean plaque area in cross-sections of the brachiocephalic trunk was measured and found to be lower in the 0.25 % cacao polyphenol group than in the control group (p < 0.05). Pathological observations showed that accumulation of cholesterol crystals in the plaque area was greater in the control group compared with the 0.40 % cacao polyphenol group (p < 0.05). Immunochemical staining in the 0.25 and 0.40 % groups showed that expression of the cell adhesion molecules (VCAM-1 and ICAM-1) and production of oxidative stress markers (4-hydroxynonenal, hexanoyl-lysine, and dityrosine) were reduced in cross-sections of the brachiocephalic trunk. These results suggest that cacao polyphenols inhibit the development of atherosclerosis in apolipoprotein E-deficient (-/-) mice by reducing oxidative stress and inflammatory responses.

  9. AI tools in computer based problem solving

    NASA Technical Reports Server (NTRS)

    Beane, Arthur J.

    1988-01-01

    The use of computers to solve value oriented, deterministic, algorithmic problems, has evolved a structured life cycle model of the software process. The symbolic processing techniques used, primarily in research, for solving nondeterministic problems, and those for which an algorithmic solution is unknown, have evolved a different model, much less structured. Traditionally, the two approaches have been used completely independently. With the advent of low cost, high performance 32 bit workstations executing identical software with large minicomputers and mainframes, it became possible to begin to merge both models into a single extended model of computer problem solving. The implementation of such an extended model on a VAX family of micro/mini/mainframe systems is described. Examples in both development and deployment of applications involving a blending of AI and traditional techniques are given.

  10. Application of AIS Technology to Forest Mapping

    NASA Technical Reports Server (NTRS)

    Yool, S. R.; Star, J. L.

    1985-01-01

    Concerns about environmental effects of large scale deforestation have prompted efforts to map forests over large areas using various remote sensing data and image processing techniques. Basic research on the spectral characteristics of forest vegetation are required to form a basis for development of new techniques, and for image interpretation. Examination of LANDSAT data and image processing algorithms over a portion of boreal forest have demonstrated the complexity of relations between the various expressions of forest canopies, environmental variability, and the relative capacities of different image processing algorithms to achieve high classification accuracies under these conditions. Airborne Imaging Spectrometer (AIS) data may in part provide the means to interpret the responses of standard data and techniques to the vegetation based on its relatively high spectral resolution.

  11. AI And Early Vision - Part II

    NASA Astrophysics Data System (ADS)

    Julesz, Bela

    1989-08-01

    A quarter of a century ago I introduced two paradigms into psychology which in the intervening years have had a direct impact on the psychobiology of early vision and an indirect one on artificial intelligence (AI or machine vision). The first, the computer-generated random-dot stereogram (RDS) paradigm (Julesz, 1960) at its very inception posed a strategic question both for AI and neurophysiology. The finding that stereoscopic depth perception (stereopsis) is possible without the many enigmatic cues of monocular form recognition - as assumed previously - demonstrated that stereopsis with its basic problem of finding matches between corresponding random aggregates of dots in the left and right visual fields became ripe for modeling. Indeed, the binocular matching problem of stereopsis opened up an entire field of study, eventually leading to the computational models of David Marr (1982) and his coworkers. The fusion of RDS had an even greater impact on neurophysiologists - including Hubel and Wiesel (1962) - who realized that stereopsis must occur at an early stage, and can be studied easier than form perception. This insight recently culminated in the studies by Gian Poggio (1984) who found binocular-disparity - tuned neurons in the input stage to the visual cortex (layer IVB in V1) in the monkey that were selectively triggered by dynamic RDS. Thus the first paradigm led to a strategic insight: that with stereoscopic vision there is no camouflage, and as such was advantageous for our primate ancestors to evolve the cortical machinery of stereoscopic vision to capture camouflaged prey (insects) at a standstill. Amazingly, although stereopsis evolved relatively late in primates, it captured the very input stages of the visual cortex. (For a detailed review, see Julesz, 1986a)

  12. Mechanism of hypertriglyceridemia in human apolipoprotein (apo) CIII transgenic mice. Diminished very low density lipoprotein fractional catabolic rate associated with increased apo CIII and reduced apo E on the particles.

    PubMed Central

    Aalto-Setälä, K; Fisher, E A; Chen, X; Chajek-Shaul, T; Hayek, T; Zechner, R; Walsh, A; Ramakrishnan, R; Ginsberg, H N; Breslow, J L

    1992-01-01

    Hypertriglyceridemia is common in the general population, but its mechanism is largely unknown. In previous work human apo CIII transgenic (HuCIIITg) mice were found to have elevated triglyceride levels. In this report, the mechanism for the hypertriglyceridemia was studied. Two different HuCIIITg mouse lines were used: a low expressor line with serum triglycerides of approximately 280 mg/dl, and a high expressor line with serum triglycerides of approximately 1,000 mg/dl. Elevated triglycerides were mainly in VLDL. VLDL particles were 1.5 times more triglyceride-rich in high expressor mice than in controls. The total amount of apo CIII (human and mouse) per VLDL particle was 2 and 2.5 times the normal amount in low and high expressors, respectively. Mouse apo E was decreased by 35 and 77% in low and high expressor mice, respectively. Under electron microscopy, VLDL particles from low and high expressor mice were found to have a larger mean diameter, 55.2 +/- 16.6 and 58.2 +/- 17.8 nm, respectively, compared with 51.0 +/- 13.4 nm from control mice. In in vivo studies, radiolabeled VLDL fractional catabolic rate (FCR) was reduced in low and high expressor mice to 2.58 and 0.77 pools/h, respectively, compared with 7.67 pools/h in controls, with no significant differences in the VLDL production rates. In an attempt to explain the reduced VLDL FCR in transgenic mice, tissue lipoprotein lipase (LPL) activity was determined in control and high expressor mice and no differences were observed. Also, VLDLs obtained from control and high expressor mice were found to be equally good substrates for purified LPL. Thus excess apo CIII in HuCIIITg mice does not cause reduced VLDL FCR by suppressing the amount of extractable LPL in tissues or making HuCIIITg VLDL a bad substrate for LPL. Tissue uptake of VLDL was studied in hepatoma cell cultures, and VLDL from transgenic mice was found to be taken up much more slowly than control VLDL (P < 0.0001), indicating that HuCIIITg VLDL is

  13. Increased HDL Size and Enhanced Apo A-I Catabolic Rates Are Associated With Doxorubicin-Induced Proteinuria in New Zealand White Rabbits.

    PubMed

    López-Olmos, Victoria; Carreón-Torres, Elizabeth; Luna-Luna, María; Flores-Castillo, Cristobal; Martínez-Ramírez, Miriam; Bautista-Pérez, Rocío; Franco, Martha; Sandoval-Zárate, Julio; Roldán, Francisco-Javier; Aranda-Fraustro, Alberto; Soria-Castro, Elizabeth; Muñoz-Vega, Mónica; Fragoso, José-Manuel; Vargas-Alarcón, Gilberto; Pérez-Méndez, Oscar

    2016-03-01

    The catabolism and structure of high-density lipoproteins (HDL) may be the determining factor of their atheroprotective properties. To better understand the role of the kidney in HDL catabolism, here we characterized HDL subclasses and the catabolic rates of apo A-I in a rabbit model of proteinuria. Proteinuria was induced by intravenous administration of doxorubicin in New Zealand white rabbits (n = 10). HDL size and HDL subclass lipids were assessed by electrophoresis of the isolated lipoproteins. The catabolic rate of HDL-apo A-I was evaluated by exogenous radiolabelling with iodine-131. Doxorubicin induced significant proteinuria after 4 weeks (4.47 ± 0.55 vs. 0.30 ± 0.02 g/L of protein in urine, P < 0.001) associated with increased uremia, creatininemia, and cardiotoxicity. Large HDL2b augmented significantly during proteinuria, whereas small HDL3b and HDL3c decreased compared to basal conditions. HDL2b, HDL2a, and HDL3a subclasses were enriched with triacylglycerols in proteinuric animals as determined by the triacylglycerol-to-phospholipid ratio; the cholesterol content in HDL subclasses remained unchanged. The fractional catabolic rate (FCR) of [(131)I]-apo A-I in the proteinuric rabbits was faster (FCR = 0.036 h(-1)) compared to control rabbits group (FCR = 0.026 h(-1), P < 0.05). Apo E increased and apo A-I decreased in HDL, whereas PON-1 activity increased in proteinuric rabbits. Proteinuria was associated with an increased number of large HDL2b particles and a decreased number of small HDL3b and 3c. Proteinuria was also connected to an alteration in HDL subclass lipids, apolipoprotein content of HDL, high paraoxonase-1 activity, and a rise in the fractional catabolic rate of the [(131)I]-apo A-I.

  14. Binding of an antibody mimetic of the human low density lipoprotein receptor to apolipoprotein E is governed through electrostatic forces. Studies using site-directed mutagenesis and molecular modeling.

    PubMed

    Raffaï, R; Weisgraber, K H; MacKenzie, R; Rupp, B; Rassart, E; Hirama, T; Innerarity, T L; Milne, R

    2000-03-10

    Monoclonal antibody 2E8 is specific for an epitope that coincides with the binding site of the low density lipoprotein receptor (LDLR) on human apoE. Its reactivity with apoE variants resembles that of the LDLR: it binds well with apoE3 and poorly with apoE2. The heavy chain complementarity-determining region (CDRH) 2 of 2E8 shows homology to the ligand-binding domain of the LDLR. To define better the structural basis of the 2E8/apoE interaction and particularly the role of electrostatic interactions, we generated and characterized a panel of 2E8 variants. Replacement of acidic residues in the 2E8 CDRHs showed that Asp(52), Glu(53), and Asp(56) are essential for high-affinity binding. Although Asp(31) (CDRH1), Glu(58) (CDRH2), and Asp(97) (CDRH3) did not appear to be critical, the Asp(97) --> Ala variant acquired reactivity with apoE2. A Thr(57) --> Glu substitution increased affinity for both apoE3 and apoE2. The affinities of wild-type 2E8 and variants for apoE varied inversely with ionic strength, suggesting that electrostatic forces contribute to both antigen binding and isoform specificity. We propose a model of the 2E8.apoE immune complex that is based on the 2E8 and apoE crystal structures and that is consistent with the apoE-binding properties of wild-type 2E8 and its variants. Given the similarity between the LDLR and 2E8 in terms of specificity, the LDLR/ligand interaction may also have an important electrostatic component.

  15. A macrophage receptor for apolipoprotein B48: Cloning, expression, and atherosclerosis

    PubMed Central

    Brown, Matthew L.; Ramprasad, M. P.; Umeda, Patrick K.; Tanaka, Akira; Kobayashi, Yasushi; Watanabe, Teruo; Shimoyamada, Hiroaki; Kuo, Wen-Lin; Li, Ran; Song, Ruiling; Bradley, William A.; Gianturco, Sandra H.

    2000-01-01

    We have cloned a human macrophage receptor that binds to apolipoprotein (apo)B48 of dietary triglyceride (TG)-rich lipoproteins. TG-rich lipoprotein uptake by the apoB48R rapidly converts macrophages and apoB48R-transfected Chinese hamster ovary cells in vitro into lipid-filled foam cells, as seen in atherosclerotic lesions. The apoB48R cDNA (3,744 bp) encodes a protein with no known homologs. Its ≈3.8-kb mRNA is expressed primarily by reticuloendothelial cells: monocytes, macrophages, and endothelial cells. Immunohistochemistry shows the apoB48R is in human atherosclerotic lesion foam cells. Normally, the apoB48R may provide essential lipids to reticuloendothelial cells. If overwhelmed, foam cell formation, endothelial dysfunction, and atherothrombogenesis may ensue, a mechanism for cardiovascular disease risk of elevated TG. PMID:10852956

  16. Ada in AI or AI in Ada. On developing a rationale for integration

    NASA Technical Reports Server (NTRS)

    Collard, Philippe E.; Goforth, Andre

    1988-01-01

    The use of Ada as an Artificial Intelligence (AI) language is gaining interest in the NASA Community, i.e., by parties who have a need to deploy Knowledge Based-Systems (KBS) compatible with the use of Ada as the software standard for the Space Station. A fair number of KBS and pseudo-KBS implementations in Ada exist today. Currently, no widely used guidelines exist to compare and evaluate these with one another. The lack of guidelines illustrates a fundamental problem inherent in trying to compare and evaluate implementations of any sort in languages that are procedural or imperative in style, such as Ada, with those in languages that are functional in style, such as Lisp. Discussed are the strengths and weakness of using Ada as an AI language and a preliminary analysis provided of factors needed for the development of criteria for the integration of these two families of languages and the environments in which they are implemented. The intent for developing such criteria is to have a logical rationale that may be used to guide the development of Ada tools and methodology to support KBS requirements, and to identify those AI technology components that may most readily and effectively be deployed in Ada.

  17. Vasculoprotective Effects of Apolipoprotein Mimetic Peptides: An Evolving Paradigm In Hdl Therapy (Vascular Disease Prevention, In Press.).

    PubMed

    White, C Roger; Datta, Geeta; Mochon, Paulina; Zhang, Zhenghao; Kelly, Ollie; Curcio, Christine; Parks, Dale; Palgunachari, Mayakonda; Handattu, Shaila; Gupta, Himanshu; Garber, David W; Anantharamaiah, G M

    2009-01-01

    Anti-atherogenic effects of high density lipoprotein (HDL) and its major protein component apolipoprotein A-I (apoA-I) are principally thought to be due to their ability to mediate reverse cholesterol transport. These agents also possess anti-oxidant properties that prevent the oxidative modification of low density lipoprotein (LDL) and anti-inflammatory properties that include inhibition of endothelial cell adhesion molecule expression. Results of the Framingham study revealed that a reduction in HDL levels is an independent risk factor for coronary artery disease (CAD). Accordingly, there has been considerable interest in developing new therapies that specifically elevate HDL cholesterol. However, recent evidence suggests that increasing circulating HDL cholesterol levels alone is not sufficient as a mode of HDL therapy. Rather, therapeutic approaches that increase the functional properties of HDL may be superior to simply raising the levels of HDL per se. Our laboratory has pioneered the development of synthetic, apolipoprotein mimetic peptides which are structurally and functionally similar to apoA-I but possess unique structural homology to the lipid-associating domains of apoA-I. The apoA-I mimetic peptide 4F inhibits atherogenic lesion formation in murine models of atherosclerosis. This effect is related to the ability of 4F to induce the formation of pre-β HDL particles that are enriched in apoA-I and paraoxonase. 4F also possesses anti-inflammatory and anti-oxidant properties that are independent of its effect on HDL quality per se. Recent studies suggest that 4F stimulates the expression of the antioxidant enzymes heme oxygenase and superoxide dismutase and inhibits superoxide anion formation in blood vessels of diabetic, hypercholesterolemic and sickle cell disease mice. The goal of this review is to discuss HDL-dependent and -independent mechanisms by which apoA-I mimetic peptides reduce vascular injury in experimental animal models.

  18. Reduced expression of the long non-coding RNA AI364715 in gastric cancer and its clinical significance.

    PubMed

    Zhu, Shengqian; Mao, Jinqin; Shao, Yongfu; Chen, Fang; Zhu, Xiaoqin; Xu, Dingli; Zhang, Xinjun; Guo, Junming

    2015-09-01

    Long non-coding RNA (lncRNA), which is greater than 200 nucleotides, is a class of RNA molecules without protein coding function. In recent years, studies have shown that lncRNAs are associated with cancers. They are affecting the occurrence and development of cancers. However, the diagnostic significances of lncRNAs in gastric cancer are largely unknown. In this study, we focused on AI364715, one typical lncRNA. A total of 186 samples were collected from two cancer centers. To find the potential association between its level and gastric cancer, we first collected 75 paired gastric cancer tissues and normal tissues, which are 5 cm away from the edge of carcinoma. Besides, 18 human healthy gastric mucosa and 18 gastric precancerous lesions (dysplasia) were also collected. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was first used to detect the expression level of AI364715 at multiple stages of gastric tumorigenesis. Then, the relationships between AI364715 level and the clinicopathological factors of patients with gastric cancer were analyzed. The results showed that the expression level of AI364715 in gastric cancer tissues was downregulated. Meanwhile, its expression level was closely associated with tumor size and differentiation. More importantly, AI364715 expression level was significantly changed in dysplasia, the typical precancerous lesions. Taken together, AI364715 may be a potential biomarker for the diagnosis of gastric cancer.

  19. Pedagogy and the PC: Trends in the AIS Curriculum

    ERIC Educational Resources Information Center

    Badua, Frank

    2008-01-01

    The author investigated the array of course topics in accounting information systems (AIS), as course syllabi embody. The author (a) used exploratory data analysis to determine the topics that AIS courses most frequently offered and (b) used descriptive statistics and econometric analysis to trace the diversity of course topics through time,…

  20. Integrating the Wall Street Journal into AIS Courses

    ERIC Educational Resources Information Center

    Kohlmeyer, James M., III

    2008-01-01

    While it is important for accounting information systems (AIS) students to understand computer technology, internal controls and business processes, such knowledge is of little use without reference to appropriate contexts. Integrating Wall Street Journal (WSJ) readings and discussions into AIS classes can enrich learning by stimulating…

  1. An Immune Agent for Web-Based AI Course

    ERIC Educational Resources Information Center

    Gong, Tao; Cai, Zixing

    2006-01-01

    To overcome weakness and faults of a web-based e-learning course such as Artificial Intelligence (AI), an immune agent was proposed, simulating a natural immune mechanism against a virus. The immune agent was built on the multi-dimension education agent model and immune algorithm. The web-based AI course was comprised of many files, such as HTML…

  2. Doctor AI: Predicting Clinical Events via Recurrent Neural Networks

    PubMed Central

    Choi, Edward; Bahadori, Mohammad Taha; Schuetz, Andy; Stewart, Walter F.; Sun, Jimeng

    2017-01-01

    Leveraging large historical data in electronic health record (EHR), we developed Doctor AI, a generic predictive model that covers observed medical conditions and medication uses. Doctor AI is a temporal model using recurrent neural networks (RNN) and was developed and applied to longitudinal time stamped EHR data from 260K patients over 8 years. Encounter records (e.g. diagnosis codes, medication codes or procedure codes) were input to RNN to predict (all) the diagnosis and medication categories for a subsequent visit. Doctor AI assesses the history of patients to make multilabel predictions (one label for each diagnosis or medication category). Based on separate blind test set evaluation, Doctor AI can perform differential diagnosis with up to 79% recall@30, significantly higher than several baselines. Moreover, we demonstrate great generalizability of Doctor AI by adapting the resulting models from one institution to another without losing substantial accuracy. PMID:28286600

  3. Serum protein changes in a rat model of chronic pain show a correlation between animal and humans

    PubMed Central

    Bellei, Elisa; Vilella, Antonietta; Monari, Emanuela; Bergamini, Stefania; Tomasi, Aldo; Cuoghi, Aurora; Guerzoni, Simona; Manca, Letizia; Zoli, Michele; Pini, Luigi Alberto

    2017-01-01

    In previous works we showed the overexpression of some proteins in biological fluids from patients suffering chronic pain. In this proteomic study we analysed serum from a rat model of neuropathic pain obtained by the chronic constriction injury (CCI) of sciatic nerve, at two time intervals, 2 and 5 weeks after the insult, to find proteins involved in the expression or mediation of pain. Sham-operated and CCI rats were treated with saline or indomethacin. Two weeks after ligation, we identified three serum proteins overexpressed in CCI rats, two of which, alpha-1-macroglobulin and vitamin D-binding protein (VDBP), remained increased 5 weeks post-surgery; at this time interval, we found increased levels of further proteins, namely apolipoprotein A-I (APOA1), apolipoprotein E (APOE), prostaglandin-H2 D-isomerase (PTGDS) and transthyretin (TTR), that overlap the overexpressed proteins found in humans. Indomethacin treatment reversed the effects of ligation. The qPCR analysis showed that transcript levels of APOA1, APOE, PTGDS and VDBP were overexpressed in the lumbar spinal cord (origin of sciatic nerve), but not in the striatum (an unrelated brain region), of CCI rats treated with saline 5 weeks after surgery, demonstrating that the lumbar spinal cord is a possible source of these proteins. PMID:28145509

  4. cDNA sequences of two apolipoproteins from lamprey

    SciTech Connect

    Pontes, M.; Xu, X.; Graham, D.; Riley, M.; Doolittle, R.F.

    1987-03-24

    The messages for two small but abundant apolipoproteins found in lamprey blood plasma were cloned with the aid of oligonucleotide probes based on amino-terminal sequences. In both cases, numerous clones were identified in a lamprey liver cDNA library, consistent with the great abundance of these proteins in lamprey blood. One of the cDNAs (LAL1) has a coding region of 105 amino acids that corresponds to a 21-residue signal peptide, a putative 8-residue propeptide, and the 76-residue mature protein found in blood. The other cDNA (LAL2) codes for a total of 191 residues, the first 23 of which constitute a signal peptide. The two proteins, which occur in the high-density lipoprotein fraction of ultracentrifuged plasma, have amino acid compositions similar to those of apolipoproteins found in mammalian blood; computer analysis indicates that the sequences are largely helix-permissive. When the sequences were searched against an amino acid sequence data base, rat apolipoprotein IV was the best matching candidate in both cases. Although a reasonable alignment can be made with that sequence and LAL1, definitive assignment of the two lamprey proteins to typical mammalian classes cannot be made at this point.

  5. A Systematic Investigation of Structure/Function Requirements for the Apolipoprotein A-I/Lecithin Cholesterol Acyltransferase Interaction Loop of High-density Lipoprotein.

    PubMed

    Gu, Xiaodong; Wu, Zhiping; Huang, Ying; Wagner, Matthew A; Baleanu-Gogonea, Camelia; Mehl, Ryan A; Buffa, Jennifer A; DiDonato, Anthony J; Hazen, Leah B; Fox, Paul L; Gogonea, Valentin; Parks, John S; DiDonato, Joseph A; Hazen, Stanley L

    2016-03-18

    The interaction of lecithin-cholesterol acyltransferase (LCAT) with apolipoprotein A-I (apoA-I) plays a critical role in high-density lipoprotein (HDL) maturation. We previously identified a highly solvent-exposed apoA-I loop domain (Leu(159)-Leu(170)) in nascent HDL, the so-called "solar flare" (SF) region, and proposed that it serves as an LCAT docking site (Wu, Z., Wagner, M. A., Zheng, L., Parks, J. S., Shy, J. M., 3rd, Smith, J. D., Gogonea, V., and Hazen, S. L. (2007) Nat. Struct. Mol. Biol. 14, 861-868). The stability and role of the SF domain of apoA-I in supporting HDL binding and activation of LCAT are debated. Here we show by site-directed mutagenesis that multiple residues within the SF region (Pro(165), Tyr(166), Ser(167), and Asp(168)) of apoA-I are critical for both LCAT binding to HDL and LCAT catalytic efficiency. The critical role for possible hydrogen bond interaction at apoA-I Tyr(166) was further supported using reconstituted HDL generated from apoA-I mutants (Tyr(166) → Glu or Asn), which showed preservation in both LCAT binding affinity and catalytic efficiency. Moreover, the in vivo functional significance of NO2-Tyr(166)-apoA-I, a specific post-translational modification on apoA-I that is abundant within human atherosclerotic plaque, was further investigated by using the recombinant protein generated from E. coli containing a mutated orthogonal tRNA synthetase/tRNACUA pair enabling site-specific insertion of the unnatural amino acid into apoA-I. NO2-Tyr(166)-apoA-I, after subcutaneous injection into hLCAT(Tg/Tg), apoA-I(-/-) mice, showed impaired LCAT activation in vivo, with significant reduction in HDL cholesteryl ester formation. The present results thus identify multiple structural features within the solvent-exposed SF region of apoA-I of nascent HDL essential for optimal LCAT binding and catalytic efficiency.

  6. A Systematic Investigation of Structure/Function Requirements for the Apolipoprotein A-I/Lecithin Cholesterol Acyltransferase Interaction Loop of High-density Lipoprotein*

    PubMed Central

    Gu, Xiaodong; Wu, Zhiping; Huang, Ying; Wagner, Matthew A.; Baleanu-Gogonea, Camelia; Mehl, Ryan A.; Buffa, Jennifer A.; DiDonato, Anthony J.; Hazen, Leah B.; Fox, Paul L.; Gogonea, Valentin; Parks, John S.; DiDonato, Joseph A.; Hazen, Stanley L.

    2016-01-01

    The interaction of lecithin-cholesterol acyltransferase (LCAT) with apolipoprotein A-I (apoA-I) plays a critical role in high-density lipoprotein (HDL) maturation. We previously identified a highly solvent-exposed apoA-I loop domain (Leu159–Leu170) in nascent HDL, the so-called “solar flare” (SF) region, and proposed that it serves as an LCAT docking site (Wu, Z., Wagner, M. A., Zheng, L., Parks, J. S., Shy, J. M., 3rd, Smith, J. D., Gogonea, V., and Hazen, S. L. (2007) Nat. Struct. Mol. Biol. 14, 861–868). The stability and role of the SF domain of apoA-I in supporting HDL binding and activation of LCAT are debated. Here we show by site-directed mutagenesis that multiple residues within the SF region (Pro165, Tyr166, Ser167, and Asp168) of apoA-I are critical for both LCAT binding to HDL and LCAT catalytic efficiency. The critical role for possible hydrogen bond interaction at apoA-I Tyr166 was further supported using reconstituted HDL generated from apoA-I mutants (Tyr166 → Glu or Asn), which showed preservation in both LCAT binding affinity and catalytic efficiency. Moreover, the in vivo functional significance of NO2-Tyr166-apoA-I, a specific post-translational modification on apoA-I that is abundant within human atherosclerotic plaque, was further investigated by using the recombinant protein generated from E. coli containing a mutated orthogonal tRNA synthetase/tRNACUA pair enabling site-specific insertion of the unnatural amino acid into apoA-I. NO2-Tyr166-apoA-I, after subcutaneous injection into hLCATTg/Tg, apoA-I−/− mice, showed impaired LCAT activation in vivo, with significant reduction in HDL cholesteryl ester formation. The present results thus identify multiple structural features within the solvent-exposed SF region of apoA-I of nascent HDL essential for optimal LCAT binding and catalytic efficiency. PMID:26797122

  7. The nonlinear association between apolipoprotein B to apolipoprotein A1 ratio and type 2 diabetes

    PubMed Central

    Mao, Yong; Xu, Yang; Lu, Leihong

    2017-01-01

    Abstract The ratio of ApoB/apolipoprotein A1 (ApoA1) has been found to be associated with type 2 diabetes, and it was proposed as a new biomarker for type 2 diabetes predictions. Previous studies have assumed that the association between apoB/apoA1 and type 2 diabetes was linear. However, the linearity assumption has rarely been examined. In the present study, we aimed to examine whether this association showed a linear trend in a nationally representative population. Participants aged 18 years and over (n = 8220) were selected from the China Health Nutrition Survey (CHNS). We used restricted cubic spline to model the association between ApoB/ApoA1 ratio and type 2 diabetes using logistic regression models. Additionally, we categorized the ApoB/ApoA1 ratio according to quartiles to compare with previous results. Age, gender, education, smoking status, high sensitivity C-reactive protein (hsCRP), lipid, body mass index (BMI), and hypertension were controlled as potential confounders. We found that the association between apoB/apoA1 ratio and type 2 diabetes may be nonlinear after adjusting for multiple potential confounders. Compared with the lowest quartile of apoB/apoA1 ratio, participants in the fourth quartile had a higher odds of type 2 diabetes [odds ratio (OR) = 1.35, 95% confidence interval (CI) = 1.01–1.81]. Our results suggest that, higher apoB/apoA1 ratio was associated with higher prevalence of type 2 diabetes. However, the association may be nonlinear. PMID:28072742

  8. Apolipoproteins and HDL cholesterol do not associate with the risk of future dementia and Alzheimer's disease: the National Finnish population study (FINRISK).

    PubMed

    Tynkkynen, Juho; Hernesniemi, Jussi A; Laatikainen, Tiina; Havulinna, Aki S; Sundvall, Jouko; Leiviskä, Jaana; Salo, Perttu; Salomaa, Veikko

    2016-12-01

    Data on associations of apolipoproteins A-I and B (apo A-I, apo B) and HDL cholesterol (HDL-C) with dementia and Alzheimer's disease (AD) are conflicting. Our aim was to examine, whether apo B, apoA-I, their ratio, or HDL-C are significant, independent predictors of incident dementia and AD in the general population free of dementia at baseline. We analyzed the results from two Finnish prospective population-based cohort studies in a total of 13,275 subjects aged 25 to 74 years with mainly Caucasian ethnicity. The follow-up time for both cohorts was 10 years. We used Cox proportional hazards regression to evaluate hazard ratios (HR) for incident dementia (including AD) (n = 220) and for AD (n = 154). Cumulative incidence function (CIF) analysis was also performed to adjust the results for competing risks of death. Adjusted for multiple dementia and AD risk factors, log-transformed apo A-I, log HDL-C, log apo B, and log apo B/A-I ratio were not associated with incident dementia or AD. HDL-C was inversely associated with AD risk when adjusted for competing risks but no other statistically significant associations were observed in the CIF analyses. Apo A-I, HDL-C, apo B, or apo B/A-I ratio were not associated with future dementia or AD. HDL-C was inversely associated with incident AD risk when adjusted for competing risks of death, but the finding is unlikely to be of clinical relevance. Our study does not support the use of these risk markers to predict incident dementia or AD.

  9. [Advances in the Association between Apolipoprotein (a) Gene Polymorphisms and Coronary Heart Disease].

    PubMed

    Zhu, Li; L, Zhan; Song, Yong-yan

    2015-08-01

    Human apolipoprotein (a) (LPA) gene is highly polymorphic, and the polymorphic loci on this gene include the Kringle 4 subtype 2(KIV-2) repeat polymorphism, the pentanucleotide repeat (TTTTA)n polymorphism, and a number of single nucleotide polymorphisms. KIV-2 repeat polymorphism was found to be significantly associated with coronary heart disease(CHD), and the reducing number of KIV-2 repeats is a risk factor for CHD. Both the increase and decrease of the pentanucleotide repeat(TTTTA)n polymorphism repeats are possibly associated with CHD risk. In single nucleotide polymorphisms loci, the rs10455872 and rs3798220 loci were widely reported to be associated with CHD, while other loci were less reported. The association between LPA polymorphisms and CHD may be mediated by either the elevation of plasma LPA level or the change of LPA subtypes. This article reviews the association between the LPA polymorphisms and CHD and the underlying mechanisms.

  10. Conformational flexibility in the apolipoprotein E amino-terminal domain structure determined from three new crystal forms: implications for lipid binding.

    PubMed Central

    Segelke, B. W.; Forstner, M.; Knapp, M.; Trakhanov, S. D.; Parkin, S.; Newhouse, Y. M.; Bellamy, H. D.; Weisgraber, K. H.; Rupp, B.

    2000-01-01

    An amino-terminal fragment of human apolipoprotein E3 (residues 1-165) has been expressed and crystallized in three different crystal forms under similar crystallization conditions. One crystal form has nearly identical cell dimensions to the previously reported orthorhombic (P2(1)2(1)2(1)) crystal form of the amino-terminal 22 kDa fragment of apolipoprotein E (residues 1-191). A second orthorhombic crystal form (P2(1)2(1)2(1) with cell dimensions differing from the first form) and a trigonal (P3(1)21) crystal form were also characterized. The structures of the first orthorhombic and the trigonal form were determined by seleno-methionine multiwavelength anomalous dispersion, and the structure of the second orthorhombic form was determined by molecular replacement using the structure from the trigonal form as a search model. A combination of modern experimental and computational techniques provided high-quality electron-density maps, which revealed new features of the apolipoprotein E structure, including an unambiguously traced loop connecting helices 2 and 3 in the four-helix bundle and a number of multiconformation side chains. The three crystal forms contain a common intermolecular, antiparallel packing arrangement. The electrostatic complimentarity observed in this antiparallel packing resembles the interaction of apolipoprotein E with the monoclonal antibody 2E8 and the low density lipoprotein receptor. Superposition of the model structures from all three crystal forms reveals flexibility and pronounced kinks in helices near one end of the four-helix bundle. This mobility at one end of the molecule provides new insights into the structural changes in apolipoprotein E that occur with lipid association. PMID:10850798

  11. Parameters influencing AIS 1 neck injury outcome in frontal impacts.

    PubMed

    Jakobsson, Lotta; Norin, Hans; Svensson, Mats Y

    2004-06-01

    In order to gain more knowledge of the neck injury scenario in frontal impacts, a statistical study of parameters influencing incidences of AIS 1 neck injuries was performed. The data set consisted of 616 occupants in Volvo cars. Information regarding the crash, the safety systems, occupant characteristics (including prior neck problems), behavior and sitting posture at the time of impact, and neck symptoms (including duration) was collected and analyzed. Occupant characteristics (mainly gender, weight, and age), kinematics (head impacts) and behavior at the time of impact were identified as the most prominent parameter areas with regard to AIS 1 neck injury outcome. Specifically, women had a significantly higher AIS 1 neck injury rate as compared to men, occupants under the age of 50 had a significantly higher AIS 1 neck injury rate as compared to those above 50 and occupants weighing less than 65 kg have a significantly higher AIS 1 neck injury rate than heavier occupants. Drivers stating that they impacted their head against a frontal interior structure had a significantly higher AIS 1 neck injury rate than those without head impact. Also, occupants who stated they had tensed their neck muscles at the time of impact, had a significantly higher AIS 1 neck injury rate as compared to occupants who did not. Occupant activities, such as tightly gripping the steering wheel or straightening their arms showed a significantly increased AIS 1 neck injury rate, indicating that occupant behavior at time of impact could be influential with respect to AIS 1 neck injury outcome. Also, occupants reporting prior neck problems had a higher rate of persistent symptoms (>1 year) but no difference with respect to passing symptoms (<3 months) as compared to those without prior neck problems. Additionally, there was no distinct pattern for the duration of neck symptoms.

  12. [Investigation of neuroprotective activity of apolipoprotein E peptide mimetic Cog1410 in transgenic lines of Drosophila melanogaster].

    PubMed

    Latypova, E M; Timoshenko, S I; Kislik, G A; Vitek, M; Shvartsman, A L; Sarantseva, S V

    2014-01-01

    The neuroprotective activity of apolipoprotein E (apoE) peptide mimetic Cog1410, containing amino acid sequence of the receptor-binding domain apoE, has been investigated in transgenic lines of Drosophila melanogaster expressing human APP and beta-secretase. Expression of two transgenes caused neuropathological processes attributed to Alzheimer's disease: neurodegeneration, cognitive abnormality and amyloid deposits formation in brain. It was shown that Cog 1410 reduces neurodegeneration in brain of transgenic flies and improves cognitive functions (odor recognition). These data suggest that Cog1410 is a potential neuroprotector that can be used in AD treatment.

  13. APOLIPOPROTEINS AND THEIR ASSOCIATION WITH CARDIOMETABOLIC RISK BIOMARKERS IN ADOLESCENTS.

    PubMed

    Neyla de Lima Albuquerque, Mellina; da Silva Diniz, Alcides; Kruze Grande de Arruda, Ilma

    2015-12-01

    Introducción: la razón apo B/apo A-I sigue siendo reportada como un predictor importante de riesgo cardiovascular, superior a lípidos, lipoproteínas y razones lipídicas convencionales. Objetivo: investigar la asociación entre las apolipoproteínas A-I y B y la razón apolipoproteína B/apolipoproteína A-I con variables de riesgo cardiometabólico en adolescentes. Métodos: estudio de corte transversal que incluye a 104 adolescentes de escuelas públicas de Recife, entre marzo/abril de 2013. Se evaluaron variables clínicas, bioquímicas, antropométricas y sociodemográficas. Se analizaron las apolipoproteínas por imunoturbidimetría. Resultados: índice de masa corporal, circunferencia de la cintura, circunferencia de la cintura/altura, triglicéridos, colesterol/HDL y apolipoproteína B/apolipoproteína A-I mostraron una reducción con la progresión de la distribución en percentil de las concentraciones de apolipoproteína A-I, mientras que HDL y apolipoproteína B aumentaron entre el primero y el último cuartil de las concentraciones de apolipoproteína A-I. Tensión arterial sistólica, índice de masa corporal, circunferencia de la cintura, circunferencia de la cintura/altura, colesterol, LDL, triglicéridos, colesterol/HDL y LDL/HDL presentaron un aumento progresivo en la distribución en cuartiles de las concentraciones de apolipoproteína B y de la apolipoproteína B/apolipoproteína A-I. Los niveles séricos de alfa-1-glicoproteína ácida aumentaron paralelamente a la progresión en percentil de apolipoproteína B. Conclusiones: los hallazgos evidencian una asociación importante de las apolipoproteínas A-I y B y de la razón apolipoproteína B/apolipoproteína A-I con biomarcadores clínicos, bioquímicos y antropométricos de riesgo cardiometabólico. Sin embargo, son recomendables estudios prospectivos para evaluar la pertenencia de la implementación de esos marcadores en la práctica clínica.

  14. AI and simulation: What can they learn from each other

    NASA Technical Reports Server (NTRS)

    Colombano, Silvano P.

    1988-01-01

    Simulation and Artificial Intelligence share a fertile common ground both from a practical and from a conceptual point of view. Strengths and weaknesses of both Knowledge Based System and Modeling and Simulation are examined and three types of systems that combine the strengths of both technologies are discussed. These types of systems are a practical starting point, however, the real strengths of both technologies will be exploited only when they are combined in a common knowledge representation paradigm. From an even deeper conceptual point of view, one might even argue that the ability to reason from a set of facts (i.e., Expert System) is less representative of human reasoning than the ability to make a model of the world, change it as required, and derive conclusions about the expected behavior of world entities. This is a fundamental problem in AI, and Modeling Theory can contribute to its solution. The application of Knowledge Engineering technology to a Distributed Processing Network Simulator (DPNS) is discussed.

  15. Utilizing AI in Temporal, Spatial, and Resource Scheduling

    NASA Technical Reports Server (NTRS)

    Stottler, Richard; Kalton, Annaka; Bell, Aaron

    2006-01-01

    Aurora is a software system enabling the rapid, easy solution of complex scheduling problems involving spatial and temporal constraints among operations and scarce resources (such as equipment, workspace, and human experts). Although developed for use in the International Space Station Processing Facility, Aurora is flexible enough that it can be easily customized for application to other scheduling domains and adapted as the requirements change or become more precisely known over time. Aurora s scheduling module utilizes artificial-intelligence (AI) techniques to make scheduling decisions on the basis of domain knowledge, including knowledge of constraints and their relative importance, interdependencies among operations, and possibly frequent changes in governing schedule requirements. Unlike many other scheduling software systems, Aurora focuses on resource requirements and temporal scheduling in combination. For example, Aurora can accommodate a domain requirement to schedule two subsequent operations to locations adjacent to a shared resource. The graphical interface allows the user to quickly visualize the schedule and perform changes reflecting additional knowledge or alterations in the situation. For example, the user might drag the activity corresponding to the start of operations to reflect a late delivery.

  16. Recent progresses on AI-2 bacterial quorum sensing inhibitors.

    PubMed

    Zhu, Peng; Li, Minyong

    2012-01-01

    Quorum sensing (QS) is a communication procedure that predominates gene expression in response to cell density and fluctuations in the neighboring environment as a result of discerning molecules termed autoinducers (AIs). It has been embroiled that QS can govern bacterial behaviors such as the secretion of virulence factors, biofilm formation, bioluminescence production, conjugation, sporulation and swarming motility. Autoinducer 2 (AI-2), a QS signaling molecule brought up to be involved in interspecies communication, exists in both gram-negative and -positive bacteria. Therefore, novel approaches to interrupt AI-2 quorum sensing are being recognized as next generation antimicrobials. In the present review article, we summarized recent progresses on AI-2 bacterial quorum sensing inhibitors and discussed their potential as the antibacterial agents.

  17. Quality measures and assurance for AI (Artificial Intelligence) software

    NASA Technical Reports Server (NTRS)

    Rushby, John

    1988-01-01

    This report is concerned with the application of software quality and evaluation measures to AI software and, more broadly, with the question of quality assurance for AI software. Considered are not only the metrics that attempt to measure some aspect of software quality, but also the methodologies and techniques (such as systematic testing) that attempt to improve some dimension of quality, without necessarily quantifying the extent of the improvement. The report is divided into three parts Part 1 reviews existing software quality measures, i.e., those that have been developed for, and applied to, conventional software. Part 2 considers the characteristics of AI software, the applicability and potential utility of measures and techniques identified in the first part, and reviews those few methods developed specifically for AI software. Part 3 presents an assessment and recommendations for the further exploration of this important area.

  18. NASA space station automation: AI-based technology review

    NASA Technical Reports Server (NTRS)

    Firschein, O.; Georgeff, M. P.; Park, W.; Neumann, P.; Kautz, W. H.; Levitt, K. N.; Rom, R. J.; Poggio, A. A.

    1985-01-01

    Research and Development projects in automation for the Space Station are discussed. Artificial Intelligence (AI) based automation technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics. AI technology will also be developed for the servicing of satellites at the Space Station, system monitoring and diagnosis, space manufacturing, and the assembly of large space structures.

  19. Apolipoprotein L1 Variant Associated with Increased Susceptibility to Trypanosome Infection

    PubMed Central

    Cuypers, Bart; Lecordier, Laurence; Meehan, Conor J.; Van den Broeck, Frederik; Imamura, Hideo; Büscher, Philippe; Dujardin, Jean-Claude; Laukens, Kris; Schnaufer, Achim; Dewar, Caroline; Lewis, Michael; Balmer, Oliver; Azurago, Thomas; Kyei-Faried, Sardick; Ohene, Sally-Ann; Duah, Boateng; Homiah, Prince; Mensah, Ebenezer Kofi; Anleah, Francis; Franco, Jose Ramon; Pays, Etienne

    2016-01-01

    ABSTRACT African trypanosomes, except Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, which cause human African trypanosomiasis, are lysed by the human serum protein apolipoprotein L1 (ApoL1). These two subspecies can resist human ApoL1 because they express the serum resistance proteins T. b. gambiense glycoprotein (TgsGP) and serum resistance-associated protein (SRA), respectively. Whereas in T. b. rhodesiense, SRA is necessary and sufficient to inhibit ApoL1, in T. b. gambiense, TgsGP cannot protect against high ApoL1 uptake, so different additional mechanisms contribute to limit this uptake. Here we report a complex interplay between trypanosomes and an ApoL1 variant, revealing important insights into innate human immunity against these parasites. Using whole-genome sequencing, we characterized an atypical T. b. gambiense infection in a patient in Ghana. We show that the infecting trypanosome has diverged from the classical T. b. gambiense strains and lacks the TgsGP defense mechanism against human serum. By sequencing the ApoL1 gene of the patient and subsequent in vitro mutagenesis experiments, we demonstrate that a homozygous missense substitution (N264K) in the membrane-addressing domain of this ApoL1 variant knocks down the trypanolytic activity, allowing the trypanosome to avoid ApoL1-mediated immunity. PMID:27073096

  20. Application of Artificial Intelligence (AI) programming techniques to tactical guidance for fighter aircraft

    NASA Technical Reports Server (NTRS)

    Mcmanus, John W.; Goodrich, Kenneth H.

    1989-01-01

    A research program investigating the use of Artificial Intelligence (AI) programming techniques to aid in the development of a Tactical Decision Generator (TDG) for Within-Visual-Range (WVR) air combat engagements is discussed. The application of AI methods for development and implementation of the TDG is presented. The history of the Adaptive Maneuvering Logic (AML) program is traced and current versions of the (AML) program is traced and current versions of the AML program are compared and contrasted with the TDG system. The Knowledge-Based Systems (KBS) used by the TDG to aid in the decision-making process are outlined and example rules are presented. The results of tests to evaluate the performance of the TDG against a version of AML and against human pilots in the Langley Differential Maneuvering Simulator (DMS) are presented. To date, these results have shown significant performance gains in one-versus-one air combat engagements.

  1. AI-2 of Aggregatibacter actinomycetemcomitans inhibits Candida albicans biofilm formation.

    PubMed

    Bachtiar, Endang W; Bachtiar, Boy M; Jarosz, Lucja M; Amir, Lisa R; Sunarto, Hari; Ganin, Hadas; Meijler, Michael M; Krom, Bastiaan P

    2014-01-01

    Aggregatibacter actinomycetemcomitans, a Gram-negative bacterium, and Candida albicans, a polymorphic fungus, are both commensals of the oral cavity but both are opportunistic pathogens that can cause oral diseases. A. actinomycetemcomitans produces a quorum-sensing molecule called autoinducer-2 (AI-2), synthesized by LuxS, that plays an important role in expression of virulence factors, in intra- but also in interspecies communication. The aim of this study was to investigate the role of AI-2 based signaling in the interactions between C. albicans and A. actinomycetemcomitans. A. actinomycetemcomitans adhered to C. albicans and inhibited biofilm formation by means of a molecule that was secreted during growth. C. albicans biofilm formation increased significantly when co-cultured with A. actinomycetemcomitans luxS, lacking AI-2 production. Addition of wild-type-derived spent medium or synthetic AI-2 to spent medium of the luxS strain, restored inhibition of C. albicans biofilm formation to wild-type levels. Addition of synthetic AI-2 significantly inhibited hypha formation of C. albicans possibly explaining the inhibition of biofilm formation. AI-2 of A. actinomycetemcomitans is synthesized by LuxS, accumulates during growth and inhibits C. albicans hypha- and biofilm formation. Identifying the molecular mechanisms underlying the interaction between bacteria and fungi may provide important insight into the balance within complex oral microbial communities.

  2. Calibrating AIS images using the surface as a reference

    NASA Technical Reports Server (NTRS)

    Smith, M. O.; Roberts, D. A.; Shipman, H. M.; Adams, J. B.; Willis, S. C.; Gillespie, A. R.

    1987-01-01

    A method of evaluating the initial assumptions and uncertainties of the physical connection between Airborne Imaging Spectrometer (AIS) image data and laboratory/field spectrometer data was tested. The Tuscon AIS-2 image connects to lab reference spectra by an alignment to the image spectral endmembers through a system gain and offset for each band. Images were calibrated to reflectance so as to transform the image into a measure that is independent of the solar radiant flux. This transformation also makes the image spectra directly comparable to data from lab and field spectrometers. A method was tested for calibrating AIS images using the surface as a reference. The surface heterogeneity is defined by lab/field spectral measurements. It was found that the Tuscon AIS-2 image is consistent with each of the initial hypotheses: (1) that the AIS-2 instrument calibration is nearly linear; (2) the spectral variance is caused by sub-pixel mixtures of spectrally distinct materials and shade, and (3) that sub-pixel mixtures can be treated as linear mixtures of pure endmembers. It was also found that the image can be characterized by relatively few endmembers using the AIS-2 spectra.

  3. A phospholipid-apolipoproteinA-I nanoparticle containing Amphotericin B as a drug delivery platform with cell membrane protective properties

    PubMed Central

    Burgess, Braydon L.; Cavigiolio, Giorgio; Fannucchi, Michelle V.; Illek, Beate; Forte, Trudy M.; Oda, Michael N.

    2010-01-01

    Amphotericin B (AMB), a potent antifungal agent, has been employed as an inhalable therapy for pulmonary fungal infections. We recently described a novel nano-sized delivery vehicle composed of phospholipid (PL) and apolipoprotein A-I, NanoDisk (ND), to which we added AMB as a payload (ND-AMB). The goal of the present study was to evaluate whether ND-AMB, compared to other formulations, preserves lung cell integrity in vitro, as AMB can be toxic to mammalian cells and reduce lung function when inhaled. Epithelial integrity was assessed by measuring K+ ion flux across a model airway epithelium, Calu-3 cells. In this assay ND-AMB was at least 8-fold less disruptive than AMB/deoxycholate (DOC). Cell viability studies confirmed this observation. Unexpectedly, the ND vehicle restored the integrity of a membrane compromised by prior exposure to AMB. An alternative formulation of ND-AMB containing a high load of AMB per ND was not protective, suggesting that ND with a low ratio of AMB to PL can sequester additional AMB from membranes. ND-AMB also protected HepG2 cells from the cytotoxicity of AMB, as determined by cellular viability and lactate dehydrogenase (LDH) levels. This study suggests that ND-AMB may be safe for administration via inhalation and reveals a unique activity whereby ND-AMB protects lung epithelial membranes from AMB toxicity. PMID:20696226

  4. Molecular Characterization and Growth Association of Two Apolipoprotein A-Ib Genes in Common Carp (Cyprinus carpio).

    PubMed

    Wang, Xinhua; Yu, Xiaomu; Tong, Jingou

    2016-09-16

    Apolipoprotein A-I (ApoA-I) is functionally involved in the transportation and metabolism of lipids in vertebrates. In this study, two isoforms of apoA-Ib in common carp (Cyprinus carpio L.) were characterized. Sequence comparison and phylogenetic analysis showed that C. carpio ApoA-Ib is relatively conserved within cyprinid fishes. During embryonic development, C. carpio apoA-Ib was first expressed at the stage of multi-cells, and the highest mRNA level was observed at the stage of optic vesicle. A ubiquitous expression pattern was detected in various tissues with extreme predominance in the liver. Significantly different expression levels were observed between light and heavy body weight groups and also in the compensatory growth test. Seventeen and eight single-nucleotide polymorphisms (SNPs) were identified in matured mRNA of the C. carpio apoA-Ib.1 and apoA-Ib.2, respectively. Two of these SNPs (apoA-Ib.2-g.183A>T and apoA-Ib.2-g.1753C>T) were significantly associated with body weight and body length in two populations of common carp. These results indicate that apoA-Ib may play an important role in the modulation of growth and development in common carp.

  5. β-COP as a Component of Transport Vesicles for HDL Apolipoprotein-Mediated Cholesterol Exocytosis

    PubMed Central

    Ma, Weilie; Lin, Margarita; Ding, Hang; Lin, Guorong; Zhang, Zhizhen

    2016-01-01

    Objective HDL and its apolipoproteins protect against atherosclerotic disease partly by removing excess cholesterol from macrophage foam cells. But the underlying mechanisms of cholesterol clearance are still not well defined. We investigated roles of vesicle trafficking of coatomer β-COP in delivering cholesterol to the cell surface during apoA-1 and apoE-mediated lipid efflux from fibroblasts and THP-1 macrophages. Methods shRNA knockout, confocal and electron microscopy and biochemical analysis were used to investigate the roles of β-COP in apolipoprotein-mediated cholesterol efflux in fibroblasts and THP-1 macrophages. Results We showed that β-COP knockdown by lentiviral shRNA resulted in reduced apoA-1-mediated cholesterol efflux, while increased cholesterol accumulation and formation of larger vesicles were observed in THP-1 macrophages by laser scanning confocal microscopy. Immunogold electron microscopy showed that β-COP appeared on the membrane protrusion complexes and colocalized with apoA-1 or apoE during cholesterol efflux. This was associated with releasing heterogeneous sizes of small particles into the culture media of THP-1 macrophage. Western blotting also showed that apoA-1 promotes β-COP translocation to the cell membrane and secretion into culture media, in which a total of 17 proteins were identified by proteomics. Moreover, β-COP exclusively associated with human plasma HDL fractions. Conclusion ApoA-1 and apoE promoted transport vesicles consisting of β-COP and other candidate proteins to exocytose cholesterol, forming the protrusion complexes on cell surface, which were then released from the cell membrane as small particles to media. PMID:26986486

  6. Apolipoprotein D takes center stage in the stress response of the aging and degenerative brain☆

    PubMed Central

    Dassati, Sarah; Waldner, Andreas; Schweigreiter, Rüdiger

    2014-01-01

    Apolipoprotein D (ApoD) is an ancient member of the lipocalin family with a high degree of sequence conservation from insects to mammals. It is not structurally related to other major apolipoproteins and has been known as a small, soluble carrier protein of lipophilic molecules that is mostly expressed in neurons and glial cells within the central and peripheral nervous system. Recent data indicate that ApoD not only supplies cells with lipophilic molecules, but also controls the fate of these ligands by modulating their stability and oxidation status. Of particular interest is the binding of ApoD to arachidonic acid and its derivatives, which play a central role in healthy brain function. ApoD has been shown to act as a catalyst in the reduction of peroxidized eicosanoids and to attenuate lipid peroxidation in the brain. Manipulating its expression level in fruit flies and mice has demonstrated that ApoD has a favorable effect on both stress resistance and life span. The APOD gene is the gene that is upregulated the most in the aging human brain. Furthermore, ApoD levels in the nervous system are elevated in a large number of neurologic disorders including Alzheimer's disease, schizophrenia, and stroke. There is increasing evidence for a prominent neuroprotective role of ApoD because of its antioxidant and anti-inflammatory activity. ApoD emerges as an evolutionarily conserved anti-stress protein that is induced by oxidative stress and inflammation and may prove to be an effective therapeutic agent against a variety of neuropathologies, and even against aging. PMID:24612673

  7. Apolipoprotein gene involved in lipid metabolism

    DOEpatents

    Rubin, Edward; Pennacchio, Len A.

    2007-07-03

    Methods and materials for studying the effects of a newly identified human gene, APOAV, and the corresponding mouse gene apoAV. The sequences of the genes are given, and transgenic animals which either contain the gene or have the endogenous gene knocked out are described. In addition, single nucleotide polymorphisms (SNPs) in the gene are described and characterized. It is demonstrated that certain SNPs are associated with diseases involving lipids and triglycerides and other metabolic diseases. These SNPs may be used alone or with SNPs from other genes to study individual risk factors. Methods for intervention in lipid diseases, including the screening of drugs to treat lipid-related or diabetic diseases are also disclosed.

  8. Apolipoprotein B-containing lipoproteins and atherosclerotic cardiovascular disease

    PubMed Central

    Shapiro, Michael D.; Fazio, Sergio

    2017-01-01

    Cholesterol-rich, apolipoprotein B (apoB)-containing lipoproteins are now widely accepted as the most important causal agents of atherosclerotic cardiovascular disease. Multiple unequivocal and orthogonal lines of evidence all converge on low-density lipoprotein and related particles as being the principal actors in the genesis of atherosclerosis. Here, we review the fundamental role of atherogenic apoB-containing lipoproteins in cardiovascular disease and several other humoral and parietal factors that are required to initiate and maintain arterial degeneration. The biology of foam cells and their interactions with high-density lipoproteins, including cholesterol efflux, are also briefly reviewed. PMID:28299190

  9. Nonreplication of an Association of Apolipoprotein E2 With Sinistrality

    PubMed Central

    Piper, Brian J.; Yasen, Alia L.; Taylor, Amy E.; Ruiz, Jonatan R.; Gaynor, J. William; Dayger, Catherine A.; Gonzalez-Gross, Marcela; Kwon, Oh D.; Nilsson, Lars-Göran; Day, Ian N. M.; Raber, Jacob; Miller, Jeremy K.

    2013-01-01

    A recent report found that left-handed adolescents were over three-fold more likely to have an Apolipoprotein (APOE) ε2 allele. This study was unable to replicate this association in young-adults (N=166). A meta-analysis of nine other datasets (N = 360 to 7,559, Power > 0.999) including that of National Alzheimer’s Coordinating Center also failed to find an over-representation of ε2 among left-handers indicating that this earlier outcome was most likely a statistical artifact. PMID:22721421

  10. Characterization of the axon initial segment (AIS) of motor neurons and identification of a para-AIS and a juxtapara-AIS, organized by protein 4.1B

    PubMed Central

    2011-01-01

    Background The axon initial segment (AIS) plays a crucial role: it is the site where neurons initiate their electrical outputs. Its composition in terms of voltage-gated sodium (Nav) and voltage-gated potassium (Kv) channels, as well as its length and localization determine the neuron's spiking properties. Some neurons are able to modulate their AIS length or distance from the soma in order to adapt their excitability properties to their activity level. It is therefore crucial to characterize all these parameters and determine where the myelin sheath begins in order to assess a neuron's excitability properties and ability to display such plasticity mechanisms. If the myelin sheath starts immediately after the AIS, another question then arises as to how would the axon be organized at its first myelin attachment site; since AISs are different from nodes of Ranvier, would this particular axonal region resemble a hemi-node of Ranvier? Results We have characterized the AIS of mouse somatic motor neurons. In addition to constant determinants of excitability properties, we found heterogeneities, in terms of AIS localization and Nav composition. We also identified in all α motor neurons a hemi-node-type organization, with a contactin-associated protein (Caspr)+ paranode-type, as well as a Caspr2+ and Kv1+ juxtaparanode-type compartment, referred to as a para-AIS and a juxtapara (JXP)-AIS, adjacent to the AIS, where the myelin sheath begins. We found that Kv1 channels appear in the AIS, para-AIS and JXP-AIS concomitantly with myelination and are progressively excluded from the para-AIS. Their expression in the AIS and JXP-AIS is independent from transient axonal glycoprotein-1 (TAG-1)/Caspr2, in contrast to juxtaparanodes, and independent from PSD-93. Data from mice lacking the cytoskeletal linker protein 4.1B show that this protein is necessary to form the Caspr+ para-AIS barrier, ensuring the compartmentalization of Kv1 channels and the segregation of the AIS, para-AIS

  11. Multiple reaction monitoring and multiple reaction monitoring cubed based assays for the quantitation of apolipoprotein F.

    PubMed

    Kumar, Abhinav; Gangadharan, Bevin; Zitzmann, Nicole

    2016-10-15

    Apolipoprotein F (APO-F) is a novel low abundance liver fibrosis biomarker and its concentration decreases in human serum and plasma across liver fibrosis stages. Current antibody based assays for APO-F suffer from limitations such as unspecific binding, antibody availability and undetectable target if the protein is degraded; and so an antibody-free assay has the potential to be a valuable diagnostic tool. We report an antibody-free, rapid, sensitive, selective and robust LC-MS/MS (MRM and MRM(3)) method for the detection and quantitation of APO-F in healthy human plasma. With further analysis of clinical samples, this LC-MS based method could be established as the first ever antibody-free biomarker assay for liver fibrosis. We explain the use of Skyline software for peptide selection and the creation of a reference library to aid in true peak identification of endogenous APO-F peptides in digests of human plasma without protein or peptide enrichment. Detection of a glycopeptide using MRM-EPI mode and reduction of interferences using MRM3 are explained. The amount of APO-F in human plasma from a healthy volunteer was determined to be 445.2ng/mL, the coefficient of variation (CV) of precision for 20 injections was <12% and the percentage error of each point along the calibration curve was calculated to be <8%, which is in line with the assay requirements for clinical samples.

  12. Targeting Apolipoproteins in Magnetic Resonance Imaging

    NASA Astrophysics Data System (ADS)

    Sriram, Renuka; Lagerstedt, Jens O.; Samardzic, Haris; Kreutzer, Ulrike; Petrolova, Jitka; Xie, Hongtao; Kaysen, George A.; Voss, John C.; Desreux, Jean F.; Jue, Thomas

    Maintaining normal physiological homeostasis depends upon a coordinated metabolism of both water-soluble and -insoluble substrates. In humans the body derives these molecules — such as glucose, amino acids, and fatty acids — from complex food matter. Water-soluble substrates can circulate readily in blood, while water-insoluble molecules — such as fatty acid, triacylglycerol, and cholesterol — require ampiphathic carriers to transport them from the site of biosynthesis (liver and intestine) to the target tissue. For fatty acid, albumin serves as the major transporter. For triacylglycerol and cholesterol, however, macromolecular complexes aggregate the hydrophobic molecules into the core and cover the surface with amphiphatic proteins and phospholipids to solubilize the particles in the lymphatic and circulatory systems. These macromolecules belong to a class of proteins, plasma lipoproteins, with specific functions and cellular targets. In the clinic these lipoproteins prognosticate the risk of cardiovascular disease (CVD). Lipoproteins divide usually into five major types: chylomicron, very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL). Each lipoprotein type exhibits characteristic density, size, and composition. As implied in the name, the density varies from the low-density chylomicron (<0.95 g/ml) to the high-density HDL (1.2 g/ml). Size also varies. The chylomicron has the largest diameter (75-1,200 nm), and HDL has the smallest (5-12 nm). The physical property variation arises from each lipoprotein's distinct composition. In a chylomicron, cholesterol, triacylglycerol, and phospholipid predominate and constitute about 90% of the particle. Protein constitutes only about 10%. In contrast, the smaller HDL has less cholesterol, triacylglycerol, and phospholipid (65% of the particle) but more protein (over 30%).

  13. Inverse modeling of biomass smoke emissions using the TOMS AI

    NASA Astrophysics Data System (ADS)

    Zhang, S. Y.; Penner, J. E.; Torres, O.

    2003-12-01

    Results of inverse modeling of biomass smoke emissions using the TOMS AI and a three-dimensional transport model are presented. The IMPACT model with DAO meteorology data in 1997 are utilized to obtain aerosol spatial and temporal distributions. Two absorbing aerosol types are considered, including biomass smoke and mineral dust. First, a radiative transfer model is applied to generate the modeled AI. Then a Bayesian inverse technique is applied to optimize the difference between the modeled AI and the EP TOMS AI in the same period by regulating monthly a priori biomass smoke emissions, while the dust emissions are fixed. The modeled AI with a posteriori emissions generally is in better agreement with the EP TOMS AI. The annual global a posteriori source increases by about 13% for the year 1997 (6.31 Tg/yr BC) in the base scenario, with a larger adjustment of monthly regional emissions. Five sensitivity scenarios are carried out, including sensitivity to the a priori uncertainties, the height of the smoke layer, the cloud screening criteria of the daily EP TOMS AI, the adjustment of emissions in a lumped region outside of the major biomass burning regions, and the covariances between observations. Results suggest that a posteriori annual global emissions in the sensitivity scenarios are within 15% of that of the base scenario. However, the difference of annual a posteriori emissions between the sensitivity scenarios and the base scenario can be as large as 50% on regional scale. We are also applying the inverse model technique to the year 2000 to compare with biomass emissions deduced from an analysis based on burned areas.

  14. The intravenous injection of oxidized LDL- or Apolipoprotein B100 – Coupled splenocytes promotes Th1 polarization in wildtype and Apolipoprotein E – Deficient mice

    SciTech Connect

    Steinmetz, Martin; Ponnuswamy, Padmapriya; Laurans, Ludivine; Esposito, Bruno; Tedgui, Alain; Mallat, Ziad

    2015-08-14

    Background: Th1 responses in atherosclerosis are mainly associated with the aggravation of atherosclerotic plaques, whereas Th2 responses lead to a less pronounced disease in mouse models. The fixation of antigens on cells by means of ethylene carbodiimide (ECDI), and subsequent injection of these antigen-coupled splenocytes (Ag-SP) to induce tolerance against the attached antigens, has been successfully used to treat murine type 1 diabetes or encephalomyelitis in. We analyzed this approach in a mouse model for atherosclerosis. Methods and results: OTII-transgenic mice that were treated with a single dose of 5 × 10{sup 7} OVA-coupled splenocytes (OVA-SP), had decreased splenocyte proliferation, and lower IFNγ production in vitro upon antigen recall. However, in vivo CD4 cell activation was increased. To try lipoprotein-derived, “atherosclerosis-associated” antigens, we first tested human oxidized LDL. In wild type mice, an increase of IFNγ production upon in vitro recall was detected in the oxLDL-SP group. In Apolipoprotein E − deficient (ApoE−/−) mice that received oxLDL-SP every 5 weeks for 20 weeks, we did not find any difference of atherosclerotic plaque burden, but again increased IFNγ production. To overcome xenogenous limitations, we then examined the effects of mouse Apolipoprotein B100 peptides P3 and P6. ApoB100-SP treatment again promoted a more IFNγ pronounced response upon in vitro recall. Flow cytometry analysis of cytokine secreting spleen cells revealed CD4 positive T cells to be mainly the source for IFNγ. In ApoE−/− mice that were administered ApoB100-SP during 20 weeks, the atherosclerotic plaque burden in aortic roots as well as total aorta was unchanged compared to PBS treated controls. Splenocyte proliferation upon antigen recall was not significantly altered in ApoB100-SP treated ApoE−/− mice. Conclusion: Although we did not observe a relevant anti-atherosclerotic benefit, the treatment with antigen

  15. Absence of apolipoprotein E protects mice from cerebral malaria.

    PubMed

    Kassa, Fikregabrail Aberra; Van Den Ham, Kristin; Rainone, Anthony; Fournier, Sylvie; Boilard, Eric; Olivier, Martin

    2016-09-20

    Cerebral malaria claims the life of millions of people each year, particularly those of children, and is a major global public health problem. Thus, the identification of novel malaria biomarkers that could be utilized as diagnostic or therapeutic targets is becoming increasingly important. Using a proteomic approach, we previously identified unique biomarkers in the sera of malaria-infected individuals, including apolipoprotein E (ApoE). ApoE is the dominant apolipoprotein in the brain and has been implicated in several neurological disorders; therefore, we were interested in the potential role of ApoE in cerebral malaria. Here we report the first demonstration that cerebral malaria is markedly attenuated in ApoE(-/-) mice. The protection provided by the absence of ApoE was associated with decreased sequestration of parasites and T cells within the brain, and was determined to be independent from the involvement of ApoE receptors and from the altered lipid metabolism associated with the knock-out mice. Importantly, we demonstrated that treatment of mice with the ApoE antagonist heparin octasaccharide significantly decreased the incidence of cerebral malaria. Overall, our study indicates that the reduction of ApoE could be utilized in the development of therapeutic treatments aimed at mitigating the neuropathology of cerebral malaria.

  16. Absence of apolipoprotein E protects mice from cerebral malaria

    PubMed Central

    Kassa, Fikregabrail Aberra; Van Den Ham, Kristin; Rainone, Anthony; Fournier, Sylvie; Boilard, Eric; Olivier, Martin

    2016-01-01

    Cerebral malaria claims the life of millions of people each year, particularly those of children, and is a major global public health problem. Thus, the identification of novel malaria biomarkers that could be utilized as diagnostic or therapeutic targets is becoming increasingly important. Using a proteomic approach, we previously identified unique biomarkers in the sera of malaria-infected individuals, including apolipoprotein E (ApoE). ApoE is the dominant apolipoprotein in the brain and has been implicated in several neurological disorders; therefore, we were interested in the potential role of ApoE in cerebral malaria. Here we report the first demonstration that cerebral malaria is markedly attenuated in ApoE−/− mice. The protection provided by the absence of ApoE was associated with decreased sequestration of parasites and T cells within the brain, and was determined to be independent from the involvement of ApoE receptors and from the altered lipid metabolism associated with the knock-out mice. Importantly, we demonstrated that treatment of mice with the ApoE antagonist heparin octasaccharide significantly decreased the incidence of cerebral malaria. Overall, our study indicates that the reduction of ApoE could be utilized in the development of therapeutic treatments aimed at mitigating the neuropathology of cerebral malaria. PMID:27647324

  17. Amphotericin B induced interdigitation of apolipoprotein stabilized nanodisk bilayers

    SciTech Connect

    Nguyen, T; Weers, P M; Sulchek, T; Hoeprich, P D; Ryan, R O

    2006-12-07

    Amphotericin B nanodisks (AMB-ND) are ternary complexes of AMB, phospholipid (PL) and apolipoprotein organized as discrete nanometer scale disk-shaped bilayers. In gel filtration chromatography experiments, empty ND lacking AMB elute as a single population of particles with a molecular weight in the range of 200 kDa. AMB-ND formulated at a 4:1 PL:AMB weight ratio, separated into two peaks. Peak 1 eluted at the position of control ND lacking AMB while the second peak, containing all of the AMB present in the original sample, eluted in the void volume. When ND prepared with increased AMB (1:1 phospholipid:AMB molar ratio) were subjected to gel filtration chromatography, an increased proportion of phospholipid and apolipoprotein were recovered in the void volume with the AMB. Prior to gel filtration the AMB-ND sample could be passed through a 0.22 {micro}m filter without loss of AMB while the voided material was lost. Native gel electrophoresis studies corroborated the gel permeation chromatography data. Far UV circular dichroism analyses revealed that apoA-I associated with AMB-ND denatures at a lower guanidine HCl concentration than apoA-I associated with ND lacking AMB. Atomic force microscopy revealed that AMB induces compression of the ND bilayer thickness consistent with bilayer interdigitation, a phenomenon that is likely related to the ability of AMB to induce pore formation in susceptible membranes.

  18. 76 FR 44045 - Establishment of the SANE/SART AI/AN Initiative Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ... of Justice Programs Establishment of the SANE/SART AI/AN Initiative Committee AGENCY: Office for... (SART) American Indian/Alaskan Native (AI/AN) Initiative (``SANE/SART AI/AN Initiative Committee'' or... (FACA), as amended, 5 U.S.C., App. 2. The SANE/SART AI/AN Initiative Committee will provide the...

  19. Surface properties of native human plasma lipoproteins and lipoprotein models.

    PubMed Central

    Massey, J B; Pownall, H J

    1998-01-01

    Plasma lipoprotein surface properties are important but poorly understood determinants of lipoprotein catabolism. To elucidate the relation between surface properties and surface reactivity, the physical properties of surface monolayers of native lipoproteins and lipoprotein models were investigated by fluorescent probes of surface lipid fluidity, surface lateral diffusion, and interfacial polarity, and by their reactivity to Naja melanoleuca phospholipase A2 (PLA2). Native lipoproteins were human very low, low-, and subclass 3 high-density lipoproteins (VLDL, LDL, and HDL3); models were 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or its ether analog in single-bilayer vesicles, large and small microemulsions of POPC and triolein, and reassembled HDL (apolipoprotein A-I plus phospholipid). Among lipoproteins, surface lipid fluidity increased in the order HDL3 < LDL < VLDL, varying inversely with their (protein + cholesterol)/phospholipid ratios. Models resembled VLDL in fluidity. Both lateral mobility in the surface monolayer and polarity of the interfacial region were lower in native lipoproteins than in models. Among native lipoproteins and models, increased fluidity in the surface monolayer was associated with increased reactivity to PLA2. Addition of cholesterol (up to 20 mol%) to models had little effect on PLA2 activity, whereas the addition of apolipoprotein C-III stimulated it. Single-bilayer vesicles, phospholipid-triolein microemulsions, and VLDL have surface monolayers that are quantitatively similar, and distinct from those of LDL and HDL3. Surface property and enzymatic reactivity differences between lipoproteins and models were associated with differences in surface monolayer protein and cholesterol contents. Thus differences in the surface properties that regulate lipolytic reactivity are a predictable function of surface composition. PMID:9533698

  20. Application of Artificial Intelligence (AI) Programming Techniques to Tactical Guidance for Fighter Aircraft

    NASA Technical Reports Server (NTRS)

    McManus, John W.; Goodrich, Kenneth H.

    1989-01-01

    A research program investigating the use of Artificial Intelligence (AI) techniques to aid in the development of a Tactical Decision Generator (TDG) for Within-Visual-Range (WVR) air combat engagements is discussed. The application of AI methods for development and implementation of the TDG is presented. The history of the Adaptive Maneuvering Logic (AML) program is traced and current versions of the AML program are compared and contrasted with the TDG system. The Knowledge-Based Systems (KBS) used by the TDG to aid in the decision-making process are outlined in detail and example rules are presented. The results of tests to evaluate the performance of the TDG versus a version of AML and versus human pilots in the Langley Differential Maneuvering Simulator (DMS) are presented. To date, these results have shown significant performance gains in one-versus-one air combat engagements, and the AI-based TDG software has proven to be much easier to modify than the updated FORTRAN AML programs.

  1. Identification of the ancestral haplotype for apolipoprotein B suggests an African origin of Homo sapiens sapiens and traces their subsequent migration to Europe and the Pacific

    SciTech Connect

    Rapacz, J.; Hasler-Rapacz, J.O. ); Chen, L.; Wu, Mingjiuan; Schumaker, V.N. ); Butler-Brunner, E.; Butler, R. )

    1991-02-15

    The probable ancestral haplotype for human apolipoprotein B (apoB) has been identified through immunological analysis of chimpanzee and gorilla serum and sequence analysis of their DNA. Moreover, the frequency of this ancestral apoB haplotype among different human populations provides strong support for the African origin of Homo sapiens sapiens and their subsequent migration from Africa to Europe and to the Pacific. The approach used here for the identification of the ancestral human apoB haplotype is likely to be applicable to many other genes.

  2. Application of AI techniques to blast furnace operations

    SciTech Connect

    Iida, Osamu; Ushijima, Yuichi; Sawada, Toshiro

    1995-10-01

    It was during the first stages of application of artificial intelligence (AI) to industrial fields, that the ironmaking division of Mizushima works at Kawasaki Steel recognized its potential. Since that time, the division has sought applications for these techniques to solve various problems. AI techniques applied to control the No. 3 blast furnace operations at the Mizushima works include: Blast furnace control by a diagnostic type of expert system that gives guidance to the actions required for blast furnace operation as well as control of furnace heat by automatically setting blast temperature; Hot stove combustion control by a combination of fuzzy inference and a physical model to insure good thermal efficiency of the stove; and blast furnace burden control using neural networks makes it possible to connect the pattern of gas flow distribution with the condition of the furnace. Experience of AI to control the blast furnace and other ironmaking operations has proved its capability for achieving automation and increased operating efficiency. The benefits are very high. For these reasons, the applications of AI techniques will be extended in the future and new techniques studied to further improve the power of AI.

  3. Discovering Knowledge from AIS Database for Application in VTS

    NASA Astrophysics Data System (ADS)

    Tsou, Ming-Cheng

    The widespread use of the Automatic Identification System (AIS) has had a significant impact on maritime technology. AIS enables the Vessel Traffic Service (VTS) not only to offer commonly known functions such as identification, tracking and monitoring of vessels, but also to provide rich real-time information that is useful for marine traffic investigation, statistical analysis and theoretical research. However, due to the rapid accumulation of AIS observation data, the VTS platform is often unable quickly and effectively to absorb and analyze it. Traditional observation and analysis methods are becoming less suitable for the modern AIS generation of VTS. In view of this, we applied the same data mining technique used for business intelligence discovery (in Customer Relation Management (CRM) business marketing) to the analysis of AIS observation data. This recasts the marine traffic problem as a business-marketing problem and integrates technologies such as Geographic Information Systems (GIS), database management systems, data warehousing and data mining to facilitate the discovery of hidden and valuable information in a huge amount of observation data. Consequently, this provides the marine traffic managers with a useful strategic planning resource.

  4. Artificial intelligence (AI) based tactical guidance for fighter aircraft

    NASA Technical Reports Server (NTRS)

    Mcmanus, John W.; Goodrich, Kenneth H.

    1990-01-01

    A research program investigating the use of artificial intelligence (AI) techniques to aid in the development of a Tactical Decision Generator (TDG) for Within Visual Range air combat engagements is discussed. The application of AI programming and problem solving methods in the development and implementation of the Computerized Logic For Air-to-Air Warfare Simulations (CLAWS), a second generation TDG, is presented. The knowledge-based systems used by CLAWS to aid in the tactical decision-making process are outlined in detail, and the results of tests to evaluate the performance of CLAWS versus a baseline TDG developed in FORTRAN to run in real time in the Langley Differential Maneuvering Simulator, are presented. To date, these test results have shown significant performance gains with respect to the TDG baseline in one-versus-one air combat engagements, and the AI-based TDG software has proven to be much easier to modify and maintain than the baseline FORTRAN TDG programs.

  5. Toward detecting California shrubland canopy chemistry with AIS data

    NASA Technical Reports Server (NTRS)

    Price, Curtis V.; Westman, Walter E.

    1987-01-01

    Airborne Imaging Spectrometer (AIS)-2 data of coastal sage scrub vegetation were examined for fine spectral features that might be used to predict concentrations of certain canopy chemical constituents. A Fourier notch filter was applied to the AIS data and the TREE and ROCK mode spectra were ratioed to a flat field. Portions of the resulting spectra resemble spectra for plant cellulose and starch in that both show reduced reflectance at 2100 and 2270 nm. The latter are regions of absorption of energy by organic bonds found in starch and cellulose. Whether the relationship is sufficient to predict the concentration of these chemicals from AIS spectra will require testing of the predictive ability of these wavebands with large field sample sizes.

  6. Frame synchronization of satellite based on AIS signals

    NASA Astrophysics Data System (ADS)

    Ma, Shexiang; Zhao, Dawei

    2016-10-01

    Frame synchronization play a very important role in coding of AIS. There are much arithmetic like maximum-likelihood, correlation and so on. But most of those cannot achieve good performance with large frequency offset. As satellite-based AIS system exist larger time delay and Doppler frequency offset, this paper propose arithmetic of frame synchronization. It is based on folding auto-correlation, where the top half and second half of training sequence have largest correlation after it is modulated by GMSK. Simulation experiments indicate that this arithmetic has good anti-frequency-offset performance.

  7. Rapid prototyping and AI programming environments applied to payload modeling

    NASA Technical Reports Server (NTRS)

    Carnahan, Richard S., Jr.; Mendler, Andrew P.

    1987-01-01

    This effort focused on using artificial intelligence (AI) programming environments and rapid prototyping to aid in both space flight manned and unmanned payload simulation and training. Significant problems addressed are the large amount of development time required to design and implement just one of these payload simulations and the relative inflexibility of the resulting model to accepting future modification. Results of this effort have suggested that both rapid prototyping and AI programming environments can significantly reduce development time and cost when applied to the domain of payload modeling for crew training. The techniques employed are applicable to a variety of domains where models or simulations are required.

  8. Diverter AI based decision aid, phases 1 and 2

    NASA Technical Reports Server (NTRS)

    Sexton, George A.; Bayles, Scott J.; Patterson, Robert W.; Schulke, Duane A.; Williams, Deborah C.

    1989-01-01

    It was determined that a system to incorporate artificial intelligence (AI) into airborne flight management computers is feasible. The AI functions that would be most useful to the pilot are to perform situational assessment, evaluate outside influences on the contemplated rerouting, perform flight planning/replanning, and perform maneuver planning. A study of the software architecture and software tools capable of demonstrating Diverter was also made. A skeletal planner known as the Knowledge Acquisition Development Tool (KADET), which is a combination script-based and rule-based system, was used to implement the system. A prototype system was developed which demonstrates advanced in-flight planning/replanning capabilities.

  9. AiGERM: A logic programming front end for GERM

    NASA Technical Reports Server (NTRS)

    Hashim, Safaa H.

    1990-01-01

    AiGerm (Artificially Intelligent Graphical Entity Relation Modeler) is a relational data base query and programming language front end for MCC (Mission Control Center)/STP's (Space Test Program) Germ (Graphical Entity Relational Modeling) system. It is intended as an add-on component of the Germ system to be used for navigating very large networks of information. It can also function as an expert system shell for prototyping knowledge-based systems. AiGerm provides an interface between the programming language and Germ.

  10. Icariin improves eNOS/NO pathway to prohibit the atherogenesis of apolipoprotein E-null mice.

    PubMed

    Xiao, Hong-Bo; Sui, Guo-Guang; Lu, Xiang-Yang

    2016-12-22

    Impaired endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) pathway induces atherogenesis. The present study examined whether icariin improves the eNOS/NO pathway to prohibit the atherogenesis of apolipoprotein E-null (ApoE(-/-)) mice. In vitro, primary human umbilical vein endothelial cells (HUVECs) were randomly divided into 7 groups: control; vehicle; icariin 10; lyphosphatidylcholine (LPC) group; LPC + icariin 1; LPC + icariin 3; and LPC + icariin 10. In vivo, 80 mice were separated randomly into 4 groups (n = 20): control, ApoE(-/-), ApoE(-/-) + icariin 10, and ApoE(-/-) + icariin 30. ApoE(-/-) mice had significantly more atherosclerosis in the aortic root together with increased aortic ROS production, body mass, plasma triglyceride (TG) and total cholesterol (TC) concentration, decreased aortic eNOS expression, and plasma NO concentration. LPC (10 μg/mL) treatment induced a big decline in NO level in the conditioned medium and eNOS expression, and an increase in intracellular reactive oxygen species (ROS) production in HUVECs. Icariin treatment decreased atherogenesis, ROS production, body mass, plasma TG concentration, and plasma TC concentration, and increased NO concentration and eNOS expression. These findings suggested icariin could improve eNOS/NO-pathway to prohibit the atherogenesis of apolipoprotein E-null mice by restraining oxidative stress.

  11. Aging, age-related macular degeneration, and the response-to-retention of apolipoprotein B-containing lipoproteins

    PubMed Central

    Curcio, Christine A.; Johnson, Mark; Huang, Jiahn-Dar; Rudolf, Martin

    2015-01-01

    The largest risk factor for age-related macular degeneration (ARMD) is advanced age. A prominent age-related change in the human retina is the accumulation of histochemically detectable neutral lipid in normal Bruch’s membrane (BrM) throughout adulthood. This change has the potential to have a major impact on physiology of the retinal pigment epithelium (RPE). It occurs in the same compartment as drusen and basal linear deposit, the pathognomonic extracellular, lipid-containing lesions of ARMD. Here we present evidence from light microscopic histochemistry, ultrastructure, lipid profiling of tissues and isolated lipoproteins, and gene expression analysis that this deposition can be accounted for by esterified cholesterol-rich, apolipoprotein B-containing lipoprotein particles constitutively produced by the RPE. This work collectively allows ARMD lesion formation and its aftermath to be conceptualized as a response to the retention of a sub-endothelial apolipoprotein B lipoprotein, similar to a widely accepted model of atherosclerotic coronary artery disease (CAD) (Tabas et al., 2007). This approach provides a wide knowledge base and sophisticated clinical armamentarium that can be readily exploited for the development of new model systems and the future benefit of ARMD patients. PMID:19698799

  12. Effects of blackberry (Morus nigra L.) consumption on serum concentration of lipoproteins, apo A-I, apo B, and high-sensitivity-C-reactive protein and blood pressure in dyslipidemic patients

    PubMed Central

    Aghababaee, Sahar Keshtkar; Vafa, Mohammadreza; Shidfar, Farzad; Tahavorgar, Atefeh; Gohari, Mahmoodreza; Katebi, Davod; Mohammadi, Vida

    2015-01-01

    Background: This study investigated blackberry (Persian mulberry) effects on apo A-I, apo B, high-sensitivity-C-reactive protein (hs-CRP), and systolic blood pressure (SBP) and diastolic blood pressure (DBP) in dyslipidemic patients. Materials and Methods: In this 8-week randomized clinical trial, 72 dyslipidemic patients were randomly divided into two groups: Intervention (300 mL/day blackberry juice with pulp) and control group (usual diets). Before and after the intervention, fasting blood samples were taken from both groups and serum concentration of lipoprotein, apo A-I and apo B, serum lipids (total cholesterol, low-density lipoprotein, high-density lipoprotein [HDL], and triglyceride), hs-CRP were measured. Blood pressure before and after the study was measured with a mercury manometer. Results: At week 8 in the intervention group, apo A-I and HDL increased significantly (P = 0.015, P = 0.001, respectively), apo B and hs-CRP decreased significantly (P = 0.044, P = 0.04, respectively). Mean changes in apo A-I and HDL and apo B/apo A-I ratio were significant between the groups (P = 0.005, P = 0.014, and P = 0.009, respectively). After 8 weeks, there was a significant difference between hs-CRP mean values (P = 0.01) of the groups. At week 8, SBP decreased significantly (P = 0.005) in the intervention group with no significant differences for SBP mean values between the groups. No significant changes were observed in other lipid parameters and DBP in the intervention group and between the groups. Conclusion: Blackberry consumption may exert beneficial effects on apolipoproteins, blood pressure, and inflammatory markers in individuals with lipid disorders. PMID:26622259

  13. Hepatosteatosis and estrogen increase apolipoprotein O production in the chicken.

    PubMed

    Schmidinger, Barbara; Weijler, Anna M; Schneider, Wolfgang J; Hermann, Marcela

    2016-08-01

    Apolipoprotein O (ApoO) is a recently discovered plasma apolipoprotein that may also play a role in the mitochondrial inner membrane. Possibly due to this complexity, its physiological functions have not been elucidated yet. To gain insight from a non-mammalian experimental system, we have investigated the regulation of ApoO levels in an alternative, well-suited model for studies on lipid metabolism, the chicken. qPCR using specific primer pairs and Western blot analysis with our rabbit anti-chicken ApoO antiserum demonstrated ApoO in the liver of chickens fed a control or a fat-enriched diet, as well as in 2 chicken hepatoma cell lines, LMH cells and the estrogen-responsive LMH-2A cells, under conditions of lipid loading by incubation with BSA-complexed oleic acid. Induced triglyceride accumulation in both the liver and the hepatic cells was associated with significantly increased levels of ApoO mRNA and protein. Furthermore, upon treatment for 24 h with estrogen of the estrogen receptor-expressing LMH-2A cells, quantitative analysis of ApoO transcripts and Western blotting revealed increases of ApoO expression. Finally, upon a single administration of estrogen to roosters that leads to hyperlipidemia, higher hepatic levels of both ApoO transcript and protein were observed within 24 h. Based on these data, we propose that hepatic expression of ApoO is tightly linked not only to diet-induced hepatosteatosis, but also to increased lipoprotein-production induced by, e.g., hormones. The findings support a role of ApoO as an effector of compromised mitochondrial function that likely accompanies the onset of non-alcoholic fatty liver disease.

  14. Mammalian embryonic cerebrospinal fluid proteome has greater apolipoprotein and enzyme pattern complexity than the avian proteome.

    PubMed

    Parada, Carolina; Gato, Angel; Bueno, David

    2005-01-01

    During early stages of embryo development, the brain cavity is filled with Embryonic Cerebro-Spinal Fluid, which has an essential role in the survival, proliferation and neurogenesis of the neuroectodermal stem cells. We identified and analyzed the proteome of Embryonic Cerebro-Spinal Fluid from rat embryos (Rattus norvegicus), which includes proteins involved in the regulation of Central Nervous System development. The comparison between mammalian and avian Embryonic Cerebro-Spinal Fluid proteomes reveals great similarity, but also greater complexity in some protein groups. The pattern of apolipoproteins and enzymes in CSF is more complex in the mammals than in birds. This difference may underlie the greater neural complexity and synaptic plasticity found in mammals. Fourteen Embryonic Cerebro-Spinal Fluid gene products were previously identified in adult human Cerebro-Spinal Fluid proteome, and interestingly they are altered in patients with neurodegenerative diseases and/or neurological disorders. Understanding these molecules and the mechanisms they control during embryonic neurogenesis may contribute to our understanding of Central Nervous System development and evolution, and these human diseases.

  15. Reading-frame restoration with an apolipoprotein B gene frameshift mutation.

    PubMed Central

    Linton, M F; Pierotti, V; Young, S G

    1992-01-01

    We examined a mutant human apolipoprotein B (apoB) allele that causes hypobetalipoproteinemia and has a single cytosine deletion in exon 26. This frameshift mutation was associated with the synthesis of a truncated apoB protein of the predicted size; however, studies in human subjects and minigene expression studies in cultured cells indicated that the mutant allele also yielded a full-length apoB protein. The 1-base-pair deletion in the mutant apoB allele created a stretch of eight consecutive adenines. To understand the mechanism whereby the mutant apoB allele yielded a full-length apoB protein, the cDNA from cells transfected with the mutant apoB minigene expression vector was examined. Splicing of the mRNA was normal; however, 11% of the cDNA clones had an additional adenine within the stretch of eight adenines, yielding nine consecutive adenines. The insertion of the extra adenine, presumably during apoB gene transcription, is predicted to restore the correct apoB reading frame, thereby permitting the synthesis of a full-length apoB protein. Images PMID:1454832

  16. AI in the Elementary, Middle, and Secondary Classroom.

    ERIC Educational Resources Information Center

    Kirkpatrick, Susan N.; Biglan, Barbara

    1990-01-01

    Describes activities that present concepts and applications of artificial intelligence (AI) for elementary and secondary school students. The use of Logo with elementary students is discussed; appropriate software is described; programing activities using Logo, BASIC, and Prolog are examined; and the field of robotics is discussed. (four…

  17. AI in CALL--Artificially Inflated or Almost Imminent?

    ERIC Educational Resources Information Center

    Schulze, Mathias

    2008-01-01

    The application of techniques from artificial intelligence (AI) to CALL has commonly been referred to as intelligent CALL (ICALL). ICALL is only slightly older than the "CALICO Journal", and this paper looks back at a quarter century of published research mainly in North America and by North American scholars. This "inventory…

  18. New directions for Artificial Intelligence (AI) methods in optimum design

    NASA Technical Reports Server (NTRS)

    Hajela, Prabhat

    1989-01-01

    Developments and applications of artificial intelligence (AI) methods in the design of structural systems is reviewed. Principal shortcomings in the current approach are emphasized, and the need for some degree of formalism in the development environment for such design tools is underscored. Emphasis is placed on efforts to integrate algorithmic computations in expert systems.

  19. Artificial Intelligence: Is the Future Now for A.I.?

    ERIC Educational Resources Information Center

    Ramaswami, Rama

    2009-01-01

    In education, artificial intelligence (AI) has not made much headway. In the one area where it would seem poised to lend the most benefit--assessment--the reliance on standardized tests, intensified by the demands of the No Child Left Behind Act of 2001, which holds schools accountable for whether students pass statewide exams, precludes its use.…

  20. State Revolving Fund American Iron and Steel (AIS) Requirement

    EPA Pesticide Factsheets

    The AIS provision requires CWSRF and DWSRF assistance recipients to use iron and steel products that are produced in the U.S. It applies to projects for the construction, alteration, maintenance, or repair of a public water system or treatment work.

  1. Automatic Identification System (AIS) Transmit Testing in Louisville Phase 2

    DTIC Science & Technology

    2014-08-01

    project. Two of the captains were Capt. David Williams and Capt. Spencer Kennedy. After leaving SCI, the team members went to Crounse Inc. and met...team members had a phone conference with Herbert Taylor (VP Operations, Kongsberg Maritime Simulation Inc.) to discuss the integration of AIS data in

  2. 33 CFR 164.46 - Automatic Identification System (AIS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... forth in IMO SN/Circ.227 (incorporated by reference, see § 164.03). Not all AIS units are able to broadcast position, course, and speed without the input of an external positioning device (e.g. dGPS); the use of other external devices (e.g. transmitting heading device, gyro, rate of turn indicator)...

  3. AI/Simulation Fusion Project at Lawrence Livermore National Laboratory

    SciTech Connect

    Erickson, S.A.

    1984-04-25

    This presentation first discusses the motivation for the AI Simulation Fusion project. After discussing very briefly what expert systems are in general, what object oriented languages are in general, and some observed features of typical combat simulations, it discusses why putting together artificial intelligence and combat simulation makes sense. We then talk about the first demonstration goal for this fusion project.

  4. Influence of Peripheral Artery Disease and Statin Therapy on Apolipoprotein Profiles

    PubMed Central

    Gardner, Andrew W.; Parker, Donald E.; Montgomery, Polly S.; Esponda, Omar L.; Casanegra, Ana I.

    2013-01-01

    Apolipoprotein B is a stronger predictor of myocardial infarction than LDL cholesterol, and it is inversely related to physical activity and modifiable with exercise training. As such, apolipoprotein measures may be of particular relevance for subjects with PAD and claudication. We compared plasma apolipoprotein profiles in 29 subjects with peripheral artery disease (PAD) and intermittent claudication and in 39 control subjects. Furthermore, we compared the plasma apolipoprotein profiles of subjects with PAD either treated (n = 17) or untreated (n = 12) with statin medications. For the apolipoprotein subparticle analyses, subjects with PAD had higher age-adjusted Lp-B:C (P < 0.05) and lower values of Lp-A-I:A-II (P < 0.05) than controls. The PAD group taking statins had lower age-adjusted values for apoB (P < 0.05), Lp-A-II:B:C:D:E (P < 0.05), Lp-B:E + Lp-B:C:E (P < 0.05), Lp-B:C (P < 0.05), and Lp-A-I (P < 0.05) than the untreated PAD group. Subjects with PAD have impaired apolipoprotein profiles than controls, characterized by Lp-B:C and Lp-A-I:A-II. Furthermore, subjects with PAD on statin medications have a more favorable risk profile, particularly noted in multiple apolipoprotein subparticles. The efficacy of statin therapy to improve cardiovascular risk appears more evident in the apolipoprotein sub-particle profile than in the more traditional lipid profile of subjects with PAD and claudication. This trial is registered with ClinicalTrials.gov NCT00618670. PMID:24102029

  5. Anti-inflammatory activity of polyphenolics from açai (Euterpe oleracea Martius) in intestinal myofibroblasts CCD-18Co cells.

    PubMed

    Dias, Manoela Maciel dos Santos; Martino, Hércia Stampini Duarte; Noratto, Giuliana; Roque-Andrade, Andrea; Stringheta, Paulo César; Talcott, Stephen; Ramos, Afonso Mota; Mertens-Talcott, Susanne U

    2015-10-01

    The demand for tropical fruits high in polyphenolics including açai (Euterpe oleracea Mart.) has been increasing based on ascribed health benefits and antioxidant properties. This study evaluated the anti-inflammatory activities of açai polyphenolics in human colon myofibroblastic CCD-18Co cells to investigate the suppression of reactive oxygen species (ROS), and mRNA and protein expression of inflammatory proteins. Non-cytotoxic concentrations of açai extract, 1-5 mg gallic acid equivalent L(-1), were selected. The generation of ROS was induced by lipopolysaccharide (LPS) and açai extract partially reversed this effect to 0.53-fold of the LPS-control. Açai extract (5 mg GAE L(-1)) down-regulated LPS-induced mRNA-expression of tumor necrosis factor alpha, TNF-α (to 0.42-fold), cyclooxygenase 2, COX-2 (to 0.61-fold), toll-like receptor-4, TLR-4 (to 0.52-fold), TNF receptor-associated factor 6, TRAF-6 (to 0.64-fold), nuclear factor kappa-B, NF-κB (to 0.76-fold), vascular cell adhesion molecule 1, VCAM-1 (to 0.71-fold) and intercellular adhesion molecule 1, ICAM-1 (to 0.68-fold). The protein levels of COX-2, TLR-4, p-NF-κB and ICAM-1 were induced by LPS and the açai extract partially reversed this effect in a dose-dependent manner. These results suggest the anti-inflammatory effect of açai polyphenolic extract in intestinal cells are at least in part mediated through the inhibition of ROS and the expression of TLR-4 and NF-κB. Results indicate the potential for açai polyphenolics in the prevention of intestinal inflammation.

  6. Smooth Muscle Cell Foam Cell Formation, Apolipoproteins, and ABCA1 in Intracranial Aneurysms: Implications for Lipid Accumulation as a Promoter of Aneurysm Wall Rupture.

    PubMed

    Ollikainen, Eliisa; Tulamo, Riikka; Lehti, Satu; Lee-Rueckert, Miriam; Hernesniemi, Juha; Niemelä, Mika; Ylä-Herttuala, Seppo; Kovanen, Petri T; Frösen, Juhana

    2016-07-01

    Saccular intracranial aneurysm (sIA) aneurysm causes intracranial hemorrhages that are associated with high mortality. Lipid accumulation and chronic inflammation occur in the sIA wall. A major mechanism for lipid clearance from arteries is adenosine triphosphate-binding cassette A1 (ABCA1)-mediated lipid efflux from foam cells to apolipoprotein A-I (apoA-I). We investigated the association of wall degeneration, inflammation, and lipid-related parameters in tissue samples of 16 unruptured and 20 ruptured sIAs using histology and immunohistochemistry. Intracellular lipid accumulation was associated with wall remodeling (p = 0.005) and rupture (p = 0.020). Foam cell formation was observed in smooth muscle cells, in addition to CD68- and CD163-positive macrophages. Macrophage infiltration correlated with intracellular lipid accumulation and apolipoproteins, including apoA-I. ApoA-I correlated with markers of lipid accumulation and wall degeneration (p = 0.01). ApoA-I-positive staining colocalized with ABCA1-positive cells particularly in sIAs with high number of smooth muscle cells (p = 0.003); absence of such colocalization was associated with wall degeneration (p = 0.017). Known clinical risk factors for sIA rupture correlated inversely with apoA-I. We conclude that lipid accumulation associates with sIA wall degeneration and risk of rupture, possibly via formation of foam cells and subsequent loss of mural cells. Reduced removal of lipids from the sIA wall via ABCA1-apoA-I pathway may contribute to this process.

  7. Association of apolipoprotein A1 and B with kidney function and chronic kidney disease in two multiethnic population samples

    PubMed Central

    Goek, Oemer-Necmi; Köttgen, Anna; Hoogeveen, Ron C.; Ballantyne, Christie M.; Coresh, Josef; Astor, Brad C.

    2012-01-01

    Background Circulating lipoproteins and their protein constituents, apolipoproteins, are risk factors for chronic kidney disease (CKD). The associations between apolipoprotein A1, apolipoprotein B and their ratio with glomerular filtration rate estimated from the new CKD Epidemiology Collaboration (CKD-EPI) equation (eGFR) are not well studied in the general population. Methods Associations between apolipoprotein A1, B and their ratio with the outcomes of eGFR, CKD (eGFR <60 mL/min/1.73m2) and albuminuria were examined in the Atherosclerosis Risk in Communities study (ARIC, n = 10 292, 1996–98) and the Third National Health and Nutrition Examination Survey (NHANES III, n = 7023, 1988–91). Cross-sectional multivariable-adjusted analyses were performed using linear and logistic regression. Prospective analyses related baseline apolipoprotein levels to subsequent CKD incidence over 10 years using the ARIC Carotid MRI follow-up cohort (n = 1659). Results Higher apolipoprotein A1 quartiles were associated with a lower prevalence of CKD [Q4 versus Q1: odds ratio (OR) 0.73, P-trend = 0.02 in ARIC; Q4 versus Q1: OR 0.53, P-trend <0.01 in NHANES III] as well as with higher eGFR (P-trend <0.01 in ARIC and NHANES III). No consistent significant associations were found for apolipoprotein B in either study. The apolipoprotein B/A1 ratio was significantly associated with eGFR across quartiles in both studies (P-trend <0.01) and with CKD in ARIC (Q4 versus Q1: OR 1.23, P-trend = 0.01). Prospectively, there were trends for the association of apolipoproteins with incident CKD [Q4 versus Q1: incidence rate ratio (IRR) = 0.68 for apolipoprotein A1, P-trend = 0.1; Q4 versus Q1: IRR = 1.35 for apolipoprotein B, P-trend = 0.2]. Associations were not systematically stronger when comparing traditional lipids (total cholesterol, low-density lipoprotein or high-density lipoprotein) to apolipoproteins. Conclusions Higher serum apolipoprotein A1 was associated with lower prevalence of CKD

  8. Detection of autoinducer (AI-2)-like activity in food samples.

    PubMed

    Sivakumar, Kirthiram K; Jesudhasan, Palmy R; Pillai, Suresh D

    2011-01-01

    The contamination, survival, and possible foodborne disease outbreaks are major issues confronting the food industry. However, from a microbial perspective, any food whether natural or processed is just another environmental niche that is available for colonization. Quorum sensing or cell-cell communication is a process by which microorganisms are thought to communicate with each other using a variety of small molecules termed autoinducers. The autoinducer AI-2 is thought to be a universal signaling molecule due to its ability to modulate the gene expression of a number of different bacterial species and genera. Pathogens such as Pseudomonas aeruginosa, Aeromonas hydrophila, Vibrio anguillarum, Streptococcus sp., and Burkholderia cepacia form biofilms on a variety of man-made and natural surfaces using cell-cell mechanisms. It is important to detect and study autoinducers and their activities in foods, since a better understanding of these molecules in food and food ingredients may help in designing new approaches to thwart microbial persistence and biofilm formation. The autoinducer AI-2 is thought to be involved in microbial attachment and biofilm formation leading to food spoilage. To better understand microbial cell-cell signaling in foods especially as it relates to pathogen persistence, biofilm formation, and food spoilage, methods to process, extract, and purify autoinducer molecules need to be developed. This chapter details methods to process food samples to obtain cell-free supernatants (CFS), which could subsequently be tested for the presence of AI-2 or "AI-2-like activity" in the extracted CFS using autoinducer bioassays. Additionally, the method of synthesizing AI-2 in the laboratory is also provided. The methods that are presented in this chapter are based on previously published research articles from the authors' laboratory.

  9. Measurement of apolipoproteins B and A by radial immunodiffusion: methodological assessment and clinical applications.

    PubMed

    Cano, M D; Gonzalvo, C; Scheen, A J; Castillo, M J

    1994-01-01

    The clinical evaluation of apolipoproteins is of interest in order to characterize the risk profile for ischemic heart disease both in normolipidemic and hyperlipidemic subjects. In the non-specialized and/or small practice clinical laboratory, the measurement of some apolipoproteins can be undertaken by simple methods of immunological analysis, among which radial immunodiffusion can be of interest due to its simplicity of use and because it does not require specific equipment. In this work several methodological questions concerning the measurement of plasma apolipoproteins B and A by radial immunodiffusion have been addressed; the results show that this method is particularly reliable for the apo B assay. Regression analysis between values obtained with radial immunodiffusion and radioimmunoassay was r = 0.972 for apo B and r = 0.782 for apo A. The recovery rate was above 90% for both apolipoproteins (93.8% for apo B and 99.5% for apo A). The inter and intraassay coefficients of variation were below 5%, and the detection limits were estimated as 9.6 mg/dl for apo A and 6.9 mg/dl for apo B. Neither the ingestion of a standard breakfast (500 Cal, 17 g fat, 120 mg cholesterol) 2 h prior to testing nor freezing the sample significantly affected the measurement of apolipoproteins B and A. Mean plasma concentrations of both apolipoproteins measured by radial immunodiffusion in normo and hyperlipidemic subjects are also presented.

  10. Scavenger receptor function of mouse Fcγ receptor III contributes to progression of atherosclerosis in apolipoprotein E hyperlipidemic mice.

    PubMed

    Zhu, Xinmei; Ng, Hang Pong; Lai, Yen-Chun; Craigo, Jodi K; Nagilla, Pruthvi S; Raghani, Pooja; Nagarajan, Shanmugam

    2014-09-01

    Recent studies showed loss of CD36 or scavenger receptor-AI/II (SR-A) does not ameliorate atherosclerosis in a hyperlipidemic mouse model, suggesting receptors other than CD36 and SR-A may also contribute to atherosclerosis. In this report, we show that apolipoprotein E (apoE)-CD16 double knockout (DKO; apoE-CD16 DKO) mice have reduced atherosclerotic lesions compared with apoE knockout mice. In vivo and in vitro foam cell analyses showed apoE-CD16 DKO macrophages accumulated less neutral lipids. Reduced foam cell formation in apoE-CD16 DKO mice is not due to change in expression of CD36, SR-A, and LOX-1. This led to a hypothesis that CD16 may have scavenger receptor activity. We presented evidence that a soluble form of recombinant mouse CD16 (sCD16) bound to malondialdehyde-modified low-density lipoprotein (MDALDL), and this binding is blocked by molar excess of MDA- modified BSA and anti-MDA mAbs, suggesting CD16 specifically recognizes MDA epitopes. Interestingly, sCD16 inhibited MDALDL binding to macrophage cell line, as well as soluble forms of recombinant mouse CD36, SR-A, and LOX-1, indicating CD16 can cross-block MDALDL binding to other scavenger receptors. Anti-CD16 mAb inhibited immune complex binding to sCD16, whereas it partially inhibited MDALDL binding to sCD16, suggesting MDALDL binding site may be in close proximity to the immune complex binding site in CD16. Loss of CD16 expression resulted in reduced levels of MDALDL-induced proinflammatory cytokine expression. Finally, CD16-deficient macrophages showed reduced MDALDL-induced Syk phosphorylation. Collectively, our findings suggest scavenger receptor activity of CD16 may, in part, contribute to the progression of atherosclerosis.

  11. GABAergic Interneuron Dysfunction Impairs Hippocampal Neurogenesis in Adult Apolipoprotein E4 Knock-in Mice

    PubMed Central

    Li, Gang; Bien-Ly, Nga; Andrews-Zwilling, Yaisa; Xu, Qin; Bernardo, Aubrey; Ring, Karen; Halabisky, Brian; Deng, Changhui; Mahley, Robert W.; Huang, Yadong

    2010-01-01

    SUMMARY Apolipoprotein (apo) E has important and diverse functions in neurobiology, and apoE4 is the major known genetic risk factor for Alzheimer’s disease. Here we report that adult neural stem/progenitor cells (NSCs) express apoE. In apoE knockout mice, neurogenesis in the hippocampus was ~60% lower than in wildtype mice, and most newborn cells developed into astrocytes rather than into neurons as in wildtype mice. This impairment was not observed in human apoE3 knock-in mice. In apoE4 knock-in mice, however, the maturation and dendritic development of newborn hippocampal neurons was significantly impaired as a result of apoE4 and its fragment-caused GABAergic interneuron dysfunction. This impairment was fully rescued by treatment with a GABAA receptor potentiator. These findings demonstrate the importance of apoE in adult hippocampal neurogenesis and show that apoE4 inhibits hippocampal neurogenesis by impairing neuronal maturation mediated by GABA signaling. PMID:19951691

  12. Gender differences in apolipoprotein D expression during aging and in Alzheimer disease.

    PubMed

    Ordóñez, Cristina; Navarro, Ana; Pérez, Cristina; Martínez, Eva; del Valle, Eva; Tolivia, Jorge

    2012-02-01

    Apolipoprotein D (Apo D) is a lipocalin expressed in a wide variety of mammalian tissues. Different studies have shown that this protein is upregulated in the central nervous system (CNS) in several neuropathological conditions, after traumatic brain injury and in aging. The Apo D promoter shows 3 estrogen response elements and it has been shown that its expression is influenced by estrogens in breast cyst fluid. The aim of this work is to study the possible relationship between gender and Apo D expression in human hippocampus and in the entorhinal and frontal cortices during aging and Alzheimer's disease (AD). We visualized Apo D immunohistochemically and then performed a quantification of the chromogen signal strength. Our findings show that Apo D expression is influenced by age, Braak stage, and sex. In most of the studied areas, Apo D expression is increased with age in women but not in men, and in AD progression in both genders. Apo D is always expressed by neurons with no signs of degeneration or death.

  13. Antibody Responses to Sarcoptes scabiei Apolipoprotein in a Porcine Model: Relevance to Immunodiagnosis of Recent Infection

    PubMed Central

    Rampton, Melanie; Walton, Shelley F.; Holt, Deborah C.; Pasay, Cielo; Kelly, Andrew; Currie, Bart J.; McCarthy, James S.; Mounsey, Kate E.

    2013-01-01

    No commercial immunodiagnostic tests for human scabies are currently available, and existing animal tests are not sufficiently sensitive. The recombinant Sarcoptes scabiei apolipoprotein antigen Sar s 14.3 is a promising immunodiagnostic, eliciting high levels of IgE and IgG in infected people. Limited data are available regarding the temporal development of antibodies to Sar s 14.3, an issue of relevance in terms of immunodiagnosis. We utilised a porcine model to prospectively compare specific antibody responses to a primary infestation by ELISA, to Sar s 14.3 and to S. scabiei whole mite antigen extract (WMA). Differences in the antibody profile between antigens were apparent, with Sar s 14.3 responses detected earlier, and declining significantly after peak infestation compared to WMA. Both antigens resulted in >90% diagnostic sensitivity from weeks 8–16 post infestation. These data provide important information on the temporal development of humoral immune responses in scabies and further supports the development of recombinant antigen based immunodiagnostic tests for recent scabies infestations. PMID:23762351

  14. The Complex Role of Apolipoprotein E in Alzheimer's Disease: an Overview and Update.

    PubMed

    Mahoney-Sanchez, Laura; Belaidi, Abdel Ali; Bush, Ashley I; Ayton, Scott

    2016-11-01

    Apolipoprotein E (ApoE) plays a crucial role in the homeostatic control of lipids in both the periphery and the central nervous system (CNS). In humans, ApoE exists in three different isoforms: ε2, ε3 and ε4. ApoE ε3 is the most common isoform, while the ε4 isoform confers the greatest genetic risk for Alzheimer's disease (AD). However, the mechanisms underlying how ApoE contributes to the pathogenesis of AD are still debated. ApoE has been shown to impact amyloid β (Aβ) deposition and clearance in the brain. ApoE also has Aβ-independent pathways in AD, which has led to the discovery of new roles of ApoE ranging from mitochondria dysfunction to, most recently, iron metabolism. Here, we review the role of ApoE in health and in AD, with the view of identifying therapeutic approaches that could prevent the risk associated with the ε4 isoform.

  15. Cytoplasmic Lipid Droplets Are Sites of Convergence of Proteasomal and Autophagic Degradation of Apolipoprotein B

    PubMed Central

    Cheng, Jinglei; Fujita, Akikazu; Tokumoto, Toshinobu

    2006-01-01

    Lipid esters stored in cytoplasmic lipid droplets (CLDs) of hepatocytes are used to synthesize very low-density lipoproteins (VLDLs), into which apolipoprotein B (ApoB) is integrated cotranslationally. In the present study, by using Huh7 cells, derived from human hepatoma and competent for VLDL secretion, we found that ApoB is highly concentrated around CLDs to make “ApoB-crescents.” ApoB-crescents were seen in <10% of Huh7 cells under normal conditions, but the ratio increased to nearly 50% after 12 h of proteasomal inhibition by N-acetyl-l-leucinyl-l-leucinyl-l-norleucinal. Electron microscopy showed ApoB to be localized to a cluster of electron-lucent particles 50–100 nm in diameter adhering to CLDs. ApoB, proteasome subunits, and ubiquitinated proteins were detected in the CLD fraction, and this ApoB was ubiquitinated. Interestingly, proteasome inhibition also caused increases in autophagic vacuoles and ApoB in lysosomes. ApoB-crescents began to decrease after 12–24 h of proteasomal inhibition, but the decrease was blocked by an autophagy inhibitor, 3-methyladenine. Inhibition of autophagy alone caused an increase in ApoB-crescents. These observations indicate that both proteasomal and autophagy/lysosomal degradation of ApoB occur around CLDs and that the CLD surface functions as a unique platform for convergence of the two pathways. PMID:16597703

  16. C-terminal interactions of apolipoprotein E4 respond to the postprandial state.

    PubMed

    Tetali, Sarada D; Budamagunta, Madhu S; Voss, John C; Rutledge, John C

    2006-07-01

    Increased triglyceride-rich lipoproteins (TGRLs) in the postprandial state are associated with atherosclerosis. We investigated whether the postprandial state induced structural changes at the apolipoprotein E4 (apoE4) C terminus, its principal lipid binding domain, using electron paramagnetic resonance (EPR) spectroscopy of a site-directed spin label attached to the cysteine of apoE4-W264C. Spin coupling between labels located in the C termini was followed after mixing with preprandial and postprandial human plasma samples. Our results indicate that postprandial plasma triggers a reorganization of the protein such that the dipolar broadening is diminished, indicating a reduction in C-terminal interaction. The loss of spectral broadening was directly correlated with an increase in postprandial plasma triglycerides and was reduced with delipidated plasma. The spin-labeled apoE4 displayed a lipid preference of VLDL > LDL > HDL in the preprandial and postprandial states. The apoE4 shift to VLDL during the postprandial state was accompanied by a loss in spectral broadening of the protein. These findings suggest that apoE4 associated with LDL maintains self-association via its C terminus and that this association is diminished in VLDL-associated protein. Lipolyzed TGRL reflected a depletion of the C-terminal interaction of apoE4. Addition of palmitate to VLDL gave a similar response as lipolyzed TGRL, suggesting that lipolysis products play a major role in reorganizing apoE4 during the postprandial state.

  17. Antiatherosclerotic and antioxidative effects of captopril in apolipoprotein E-deficient mice.

    PubMed

    Hayek, T; Attias, J; Smith, J; Breslow, J L; Keidar, S

    1998-04-01

    The effect of the angiotensin-converting enzyme (ACE) inhibitor, captopril, on the development of atherosclerosis was determined in the apolipoprotein (apo) E-deficient mice. These mice develop severe hypercholesterolemia and extensive atherosclerotic lesions on chow diet, similar to those found in humans. Furthermore, in these mice, accelerated atherosclerosis is associated with increased plasma lipid peroxidation, a phenomenon that may play a crucial role in the buildup of the atherosclerotic lesions. Mice received either placebo or 50 mg/kg/day of captopril. After 12 weeks of treatment, captopril reduced the aortic-lesion area by 70% compared with that of the placebo-treated group. Captopril also increased the resistance of low-density lipoprotein (LDL) to CuSO4-induced oxidative stress, as shown by a significant reduction in the LDL content of malondialdehyde (MDA) by 30%, as well as by the prolongation of the lag time required for LDL oxidation from 55 min in the placebo-treated mice to 70 min in the captopril-treated mice, and reduction of the maximum LDL oxidation at 150 min by 35%. In vitro studies demonstrated that preincubation of LDL with captopril, inhibited the onset of CuSO4-induced LDL peroxidation up to 120 min, and reduced the LDL content of MDA by 90%. We conclude that captopril attenuates atherosclerosis in the apo E-deficient mice, and this phenomenon may be related to its inhibitory effect on the plasma LDL oxidation.

  18. Acute exposure to apolipoprotein A1 inhibits macrophage chemotaxis in vitro and monocyte recruitment in vivo

    PubMed Central

    Iqbal, Asif J; Barrett, Tessa J; Taylor, Lewis; McNeill, Eileen; Manmadhan, Arun; Recio, Carlota; Carmineri, Alfredo; Brodermann, Maximillian H; White, Gemma E; Cooper, Dianne; DiDonato, Joseph A; Zamanian-Daryoush, Maryam; Hazen, Stanley L; Channon, Keith M

    2016-01-01

    Apolipoprotein A1 (apoA1) is the major protein component of high-density lipoprotein (HDL) and has well documented anti-inflammatory properties. To better understand the cellular and molecular basis of the anti-inflammatory actions of apoA1, we explored the effect of acute human apoA1 exposure on the migratory capacity of monocyte-derived cells in vitro and in vivo. Acute (20–60 min) apoA1 treatment induced a substantial (50–90%) reduction in macrophage chemotaxis to a range of chemoattractants. This acute treatment was anti-inflammatory in vivo as shown by pre-treatment of monocytes prior to adoptive transfer into an on-going murine peritonitis model. We find that apoA1 rapidly disrupts membrane lipid rafts, and as a consequence, dampens the PI3K/Akt signalling pathway that coordinates reorganization of the actin cytoskeleton and cell migration. Our data strengthen the evidence base for therapeutic apoA1 infusions in situations where reduced monocyte recruitment to sites of inflammation could have beneficial outcomes. DOI: http://dx.doi.org/10.7554/eLife.15190.001 PMID:27572261

  19. Mutations of the apolipoprotein A5 gene with inherited hypertriglyceridaemia: review of the current literature.

    PubMed

    Melegh, B I; Duga, B; Sümegi, K; Kisfali, P; Maász, A; Komlósi, K; Hadzsiev, K; Komoly, S; Kosztolányi, G; Melegh, B

    2012-01-01

    Apoliporotein A5 (APOA5), a member of the apolipoprotein family, plays a key regulatory role in triglyceride (TG) metabolism. Even though the exact biochemical background of its mechanism is not yet fully understood, diseases associated with this particular gene highlighted its key role in the metabolism of triglycerides in humans. Naturally occurring functional variants of the gene and their natural major haplotypes are known to associate with moderately elevated triglyceride levels, and are also known to confer risk or protection for major polygenic diseases, like coronary heart disease, stroke, or metabolic syndrome. On the other hand, case reports and even robust resequencing studies verified APOA5 mutations as underlying genetic defects behind extreme hypertriglyceridemic phenotype. Soon after the recognition of the first cases, there were indications which suggest the existence of less frequent genetic variants which, in combination with the common allelic variants of the gene, can define haplotypes that are associated with substantial triglyceride level increase. In addition, it became evident, that there are rare mutations of the APOA5 gene which can be associated with specific complex phenotypes and different types of hyperlipoproteinemia, which includes extremely high triglyceride levels with multiple organ pathology. These rare mutations may cause inheritable hypertriglyceridemia, but they presented at a low frequency and could not be captured by standard genotyping array screenings. The identification of new mutations still relies on the direct sequencing of APOA5 gene of patients with hypertriglyceridemia with an unusual pattern, individually or in huge resequencing studies.

  20. Evolutionary analysis of apolipoprotein E by Maximum Likelihood and complex network methods

    PubMed Central

    Benevides, Leandro de Jesus; de Carvalho, Daniel Santana; Andrade, Roberto Fernandes Silva; Bomfim, Gilberto Cafezeiro; Fernandes, Flora Maria de Campos

    2016-01-01

    Abstract Apolipoprotein E (apo E) is a human glycoprotein with 299 amino acids, and it is a major component of very low density lipoproteins (VLDL) and a group of high-density lipoproteins (HDL). Phylogenetic studies are important to clarify how various apo E proteins are related in groups of organisms and whether they evolved from a common ancestor. Here, we aimed at performing a phylogenetic study on apo E carrying organisms. We employed a classical and robust method, such as Maximum Likelihood (ML), and compared the results using a more recent approach based on complex networks. Thirty-two apo E amino acid sequences were downloaded from NCBI. A clear separation could be observed among three major groups: mammals, fish and amphibians. The results obtained from ML method, as well as from the constructed networks showed two different groups: one with mammals only (C1) and another with fish (C2), and a single node with the single sequence available for an amphibian. The accordance in results from the different methods shows that the complex networks approach is effective in phylogenetic studies. Furthermore, our results revealed the conservation of apo E among animal groups. PMID:27560837

  1. 78 FR 17232 - Meeting of the SANE/SART AI/AN Initiative Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ... Indian/ Alaska Native (AI/AN) Sexual Assault Nurse Examiner (SANE)--Sexual Assault Response Team (SART.../Alaskan Native (AI/AN) Sexual Assault Nurse Examiner (SANE)--Sexual Assault Response Team...

  2. Google Earth Visualizations of the Marine Automatic Identification System (AIS): Monitoring Ship Traffic in National Marine Sanctuaries

    NASA Astrophysics Data System (ADS)

    Schwehr, K.; Hatch, L.; Thompson, M.; Wiley, D.

    2007-12-01

    The Automatic Identification System (AIS) is a new technology that provides ship position reports with location, time, and identity information without human intervention from ships carrying the transponders to any receiver listening to the broadcasts. In collaboration with the USCG's Research and Development Center, NOAA's Stellwagen Bank National Marine Sanctuary (SBNMS) has installed 3 AIS receivers around Massachusetts Bay to monitor ship traffic transiting the sanctuary and surrounding waters. The SBNMS and the USCG also worked together propose the shifting the shipping lanes (termed the traffic separation scheme; TSS) that transit the sanctuary slightly to the north to reduce the probability of ship strikes of whales that frequent the sanctuary. Following approval by the United Nation's International Maritime Organization, AIS provided a means for NOAA to assess changes in the distribution of shipping traffic caused by formal change in the TSS effective July 1, 2007. However, there was no easy way to visualize this type of time series data. We have created a software package called noaadata-py to process the AIS ship reports and produce KML files for viewing in Google Earth. Ship tracks can be shown changing over time to allow the viewer to feel the motion of traffic through the sanctuary. The ship tracks can also be gridded to create ship traffic density reports for specified periods of time. The density is displayed as map draped on the sea surface or as vertical histogram columns. Additional visualizations such as bathymetry images, S57 nautical charts, and USCG Marine Information for Safety and Law Enforcement (MISLE) can be combined with the ship traffic visualizations to give a more complete picture of the maritime environment. AIS traffic analyses have the potential to give managers throughout NOAA's National Marine Sanctuaries an improved ability to assess the impacts of ship traffic on the marine resources they seek to protect. Viewing ship traffic

  3. Effect of aerobic exercise on risk factors of cardiovascular disease and the apolipoprotein B / apolipoprotein a-1 ratio in obese woman.

    PubMed

    Kim, Dae-Young; Jung, Sun-Young

    2014-11-01

    [Purpose] The objective of this study was to confirm whether consistent aerobic exercise has an effect on the apolipoprotein B/apolipoprotein A-1 ratio or reduces the risk of cardiovascular disease in obese women. [Subjects and Methods] The participants included 32 obese women between the ages of 40 and 49. Subjects were randomly divided into two groups (n = 16 in each group): the control group and the exercise group. The exercise program in this study corresponded to an intensity of 50 to 60% of the maximum volume of minute oxygen consumption and was performed three times per week over 12 weeks. Physical measurements, measurement of cardiorespiratory fitness and blood pressure, and blood collection were done before and after the 12 weeks of exercise at the same time and under the same conditions. [Results] Based on the results of this study, there were significant interaction effects in both time and group weight, for body mass index, percent body fat, maximum volume of minute oxygen consumption, high-density lipoprotein cholesterol, and the apolipoprotein B/apolipoprotein A-1 ratio. Moreover, waist circumference, total cholesterol, and the atherogenic index decreased significantly after 12 weeks of aerobic exercise. [Conclusion] Regular aerobic exercise effectively improved cardiovascular risk factors and decreased the obesity index in obese women.

  4. 10 CFR 1017.28 - Processing on Automated Information Systems (AIS).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Processing on Automated Information Systems (AIS). 1017.28... UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION Physical Protection Requirements § 1017.28 Processing on Automated Information Systems (AIS). UCNI may be processed or produced on any AIS that complies with the guidance in...

  5. 10 CFR 1017.28 - Processing on Automated Information Systems (AIS).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Processing on Automated Information Systems (AIS). 1017.28... UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION Physical Protection Requirements § 1017.28 Processing on Automated Information Systems (AIS). UCNI may be processed or produced on any AIS that complies with the guidance in...

  6. 10 CFR 1017.28 - Processing on Automated Information Systems (AIS).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Processing on Automated Information Systems (AIS). 1017.28... UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION Physical Protection Requirements § 1017.28 Processing on Automated Information Systems (AIS). UCNI may be processed or produced on any AIS that complies with the guidance in...

  7. 10 CFR 1017.28 - Processing on Automated Information Systems (AIS).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Processing on Automated Information Systems (AIS). 1017.28... UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION Physical Protection Requirements § 1017.28 Processing on Automated Information Systems (AIS). UCNI may be processed or produced on any AIS that complies with the guidance in...

  8. 10 CFR 1017.28 - Processing on Automated Information Systems (AIS).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Processing on Automated Information Systems (AIS). 1017.28... UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION Physical Protection Requirements § 1017.28 Processing on Automated Information Systems (AIS). UCNI may be processed or produced on any AIS that complies with the guidance in...

  9. Oil spills and AI: How to manage resources through simulation

    SciTech Connect

    Giribone, P.; Bruzzone, A.G.; Caddeo, S.

    1995-12-31

    Today, in the Mediterranean theater of the Upper Tyrrhenian, the ecological risk involving oil installations is still quite high. This is due to the fact that valuable environmental and tourist areas exist together with large industrial and port structures; in particular, recent events have demonstrated the danger involving oil spills along the Ligurian coastline. This study proposes an approach to plan the operations that should be performed when accidents occur, based on the use of AI techniques.

  10. AiResearch QCGAT engine performance and emissions tests

    NASA Technical Reports Server (NTRS)

    Norgren, W. M.

    1980-01-01

    Results of aerodynamic performance and emission tests, conducted on a specially designed QCGAT engine in the 17,793-N (4,000 lb) thrust class, are presented. Performance of the AiResearch QCGAT engine was excellent throughout all testing. No serious mechanical malfunctions were encountered, and no significant test time was lost due to engine-related problems. Emissions were drastically reduced over similar engines, and the engine exhibited good smoke performance.

  11. Artificial intelligence (AI) systems for interpreting complex medical datasets.

    PubMed

    Altman, R B

    2017-02-09

    Advances in machine intelligence have created powerful capabilities in algorithms that find hidden patterns in data, classify objects based on their measured characteristics, and associate similar patients/diseases/drugs based on common features. However, artificial intelligence (AI) applications in medical data have several technical challenges: complex and heterogeneous datasets, noisy medical datasets, and explaining their output to users. There are also social challenges related to intellectual property, data provenance, regulatory issues, economics, and liability.

  12. The AIS: A Spectrograph/Imager Ensemble for Space Flight

    DTIC Science & Technology

    1990-05-17

    emissions in the vicinity of spacecraft. It includes nine spectrographs, which cover the spectral range from 115 to 1100 snm#.Vlithpe- tralI ...designations, wavelength ranges, and fields of view. 10 3. Spectrograph parameters and calibration results . 26 4. Imager parameters and calibration... results . 28 BI Weights and Dimensions of the boxes that comprise the AIS 42 Accession For NTIS GRA& DTIC TAB 0 Unamotced E0 Just ificat1o by Distrlbution

  13. Extracting uranium from seawater: Promising AI series adsorbents

    DOE PAGES

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; ...

    2015-11-10

    A series of adsorbent (AI10 through AI17) were successfully developed at ORNL by radiation induced graft polymerization (RIGP) of acrylonitrile (AN) and vinylphosphonic acid (VPA) (at different mole/mole ratios) onto high surface area polyethylene fiber, with higher degree of grafting which ranges from 110 300%. The grafted nitrile groups were converted to amidoxime groups by reaction with 10 wt% hydroxylamine at 80 C for 72 hours. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8 ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged frommore » 171-187 g-U/kg-ads irrespective of %DOG. The performance of the adsorbents for uranium adsorption in natural seawater was also carried out using flow-through-column at Pacific Northwest National Laboratory (PNNL). The three hours KOH conditioning was better for higher uranium uptake than one hour. The adsorbent AI11 containing AN and VPA at the mole ration of 3.52, emerged as the potential candidate for higher uranium adsorption (3.35 g-U/Kg-ads.) after 56 days of exposure in the seawater in the flow-through-column. The rate vanadium adsorption over uranium was linearly increased throughout the 56 days exposure. The total vanadium uptake was ~5 times over uranium after 56 days.« less

  14. Extracting Uranium from Seawater: Promising AI Series Adsorbents

    SciTech Connect

    Das, S.; Oyola, Y.; Mayes, R. T.; Janke, C. J.; Kuo, L. -J.; Gill, G.; Wood, J. R.; Dai, S.

    2016-04-20

    A new series of adsorbents (AI10 through AI17) were successfully developed at ORNL by radiation induced graft polymerization (RIGP) of acrylonitrile (AN) and vinylphosphonic acid (VPA) (at different mole to mole ratios) onto high surface area polyethylene fiber, with high degrees of grafting (DOG) varying from 110 to 300%. The grafted nitrile groups were converted to amidoxime groups by reaction with 5 wt % hydroxylamine at 80 °C for 72 h. The amidoximated adsorbents were then conditioned with 0.44 M KOH at 80 °C followed by screening at ORNL with prescreening brine spiked with 8 ppm uranium. Uranium adsorption capacities in prescreening ranged from 171 to 187 g-U/kg-ads irrespective of percent DOG. The performance of the adsorbents with respect to uranium adsorption in natural seawater was also investigated using flow-throughcolumn testing at the Pacific Northwest National Laboratory (PNNL). Three hours of KOH conditioning led to higher uranium uptake than 1 h of conditioning. The adsorbent AI11, containing AN and VPA at the mole ratio of 3.52, emerged as the potential candidate for the highest uranium adsorption (3.35 g-U/kg-ads.) after 56 days of exposure in seawater flow-through-columns. The rate of vanadium adsorption over uranium linearly increased throughout the 56 days of exposure. The total mass of vanadium uptake was ~5 times greater than uranium after 56 days.

  15. Functional subdivisions in low-frequency primary auditory cortex (AI).

    PubMed

    Wallace, M N; Palmer, A R

    2009-04-01

    We wished to test the hypothesis that there are modules in low-frequency AI that can be identified by their responsiveness to communication calls or particular regions of space. Units were recorded in anaesthetised guinea pig AI and stimulated with conspecific vocalizations and a virtual motion stimulus (binaural beats) presented via a closed sound system. Recording tracks were mainly oriented orthogonally to the cortical surface. Some of these contained units that were all time-locked to the structure of the chutter call (14/22 tracks) and/or the purr call (12/22 tracks) and/or that had a preference for stimuli from a particular region of space (8/20 tracks with four contralateral, two ipsilateral and two midline), or where there was a strong asymmetry in the response to beats of different direction (two tracks). We conclude that about half of low-frequency AI is organized into modules that are consistent with separate "what" and "where" pathways.

  16. LUT observations of the mass-transferring binary AI Dra

    NASA Astrophysics Data System (ADS)

    Liao, Wenping; Qian, Shengbang; Li, Linjia; Zhou, Xiao; Zhao, Ergang; Liu, Nianping

    2016-06-01

    Complete UV band light curve of the eclipsing binary AI Dra was observed with the Lunar-based Ultraviolet Telescope (LUT) in October 2014. It is very useful to adopt this continuous and uninterrupted light curve to determine physical and orbital parameters of the binary system. Photometric solutions of the spot model are obtained by using the W-D (Wilson and Devinney) method. It is confirmed that AI Dra is a semi-detached binary with secondary component filling its critical Roche lobe, which indicates that a mass transfer from the secondary component to the primary one should happen. Orbital period analysis based on all available eclipse times suggests a secular period increase and two cyclic variations. The secular period increase was interpreted by mass transfer from the secondary component to the primary one at a rate of 4.12 ×10^{-8}M_{⊙}/yr, which is in agreement with the photometric solutions. Two cyclic oscillations were due to light travel-time effect (LTTE) via the presence of two cool stellar companions in a near 2:1 mean-motion resonance. Both photometric solutions and orbital period analysis confirm that AI Dra is a mass-transferring binary, the massive primary is filling 69 % of its critical Roche lobe. After the primary evolves to fill the critical Roche lobe, the mass transfer will be reversed and the binary will evolve into a contact configuration.

  17. Extracting uranium from seawater: Promising AI series adsorbents

    SciTech Connect

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; Janke, Christopher James; Kuo, Li-Jung; Gill, Gary; Wood, Jordana; Dai, Sheng

    2015-11-10

    A series of adsorbent (AI10 through AI17) were successfully developed at ORNL by radiation induced graft polymerization (RIGP) of acrylonitrile (AN) and vinylphosphonic acid (VPA) (at different mole/mole ratios) onto high surface area polyethylene fiber, with higher degree of grafting which ranges from 110 300%. The grafted nitrile groups were converted to amidoxime groups by reaction with 10 wt% hydroxylamine at 80 C for 72 hours. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8 ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 171-187 g-U/kg-ads irrespective of %DOG. The performance of the adsorbents for uranium adsorption in natural seawater was also carried out using flow-through-column at Pacific Northwest National Laboratory (PNNL). The three hours KOH conditioning was better for higher uranium uptake than one hour. The adsorbent AI11 containing AN and VPA at the mole ration of 3.52, emerged as the potential candidate for higher uranium adsorption (3.35 g-U/Kg-ads.) after 56 days of exposure in the seawater in the flow-through-column. The rate vanadium adsorption over uranium was linearly increased throughout the 56 days exposure. The total vanadium uptake was ~5 times over uranium after 56 days.

  18. The AI Bus architecture for distributed knowledge-based systems

    NASA Technical Reports Server (NTRS)

    Schultz, Roger D.; Stobie, Iain

    1991-01-01

    The AI Bus architecture is layered, distributed object oriented framework developed to support the requirements of advanced technology programs for an order of magnitude improvement in software costs. The consequent need for highly autonomous computer systems, adaptable to new technology advances over a long lifespan, led to the design of an open architecture and toolbox for building large scale, robust, production quality systems. The AI Bus accommodates a mix of knowledge based and conventional components, running on heterogeneous, distributed real world and testbed environment. The concepts and design is described of the AI Bus architecture and its current implementation status as a Unix C++ library or reusable objects. Each high level semiautonomous agent process consists of a number of knowledge sources together with interagent communication mechanisms based on shared blackboards and message passing acquaintances. Standard interfaces and protocols are followed for combining and validating subsystems. Dynamic probes or demons provide an event driven means for providing active objects with shared access to resources, and each other, while not violating their security.

  19. Artificial Intelligence (AI) Based Tactical Guidance for Fighter Aircraft

    NASA Technical Reports Server (NTRS)

    McManus, John W.; Goodrich, Kenneth H.

    1990-01-01

    A research program investigating the use of Artificial Intelligence (AI) techniques to aid in the development of a Tactical Decision Generator (TDG) for Within Visual Range (WVR) air combat engagements is discussed. The application of AI programming and problem solving methods in the development and implementation of the Computerized Logic For Air-to-Air Warfare Simulations (CLAWS), a second generation TDG, is presented. The Knowledge-Based Systems used by CLAWS to aid in the tactical decision-making process are outlined in detail, and the results of tests to evaluate the performance of CLAWS versus a baseline TDG developed in FORTRAN to run in real-time in the Langley Differential Maneuvering Simulator (DMS), are presented. To date, these test results have shown significant performance gains with respect to the TDG baseline in one-versus-one air combat engagements, and the AI-based TDG software has proven to be much easier to modify and maintain than the baseline FORTRAN TDG programs. Alternate computing environments and programming approaches, including the use of parallel algorithms and heterogeneous computer networks are discussed, and the design and performance of a prototype concurrent TDG system are presented.

  20. Recombinant neural protein PrP can bind with both recombinant and native apolipoprotein E in vitro.

    PubMed

    Gao, Chen; Lei, Yan-Jun; Han, Jun; Shi, Qi; Chen, Lan; Guo, Yan; Gao, Yong-Jun; Chen, Jian-Ming; Jiang, Hui-Ying; Zhou, Wei; Dong, Xiao-Ping

    2006-09-01

    The most essential and crucial step during the pathogenesis of transmissible spongiform encephalopathy is the conformational change of cellular prion protein (PrP(C)) to pathologic isoform (PrP(Sc)). A lot of data revealed that caveolae-like domains (CLDs) in the cell surface were the probable place where the conversion of PrP proteins happened. Apolipoprotein E (ApoE) is an apolipoprotein which is considered to play an important role in the development of Alzheimer's disease and other neurodegenerative diseases by forming protein complex through binding to the receptor located in the clathrin-coated pits of the cell surface. In this study, a 914-bp cDNA sequence encoding human ApoE3 was amplified from neuroblastoma cell line SH-SY5Y. Three human ApoE isomers were expressed and purified from Escherichia coli. ApoE-specific antiserum was prepared by immunizing rabbits with the purified ApoE3. GST/His pull-down assay, immunoprecipitation and ELISA revealed that three full-length ApoE isomers interact with the recombinant full-length PrP protein in vitro. The regions corresponding to protein binding were mapped in the N-terminal segment of ApoE (amino acid 1-194) and the N-terminal of PrP (amino acid 23-90). Moreover, the recombinant PrP showed the ability to form a complex with the native ApoE from liver tissues. Our data provided direct evidence of molecular interaction between ApoE and PrP. It also supplied scientific clues for assessing the significance of CLDs on the surface of cellular membrane in the process of conformational conversion from PrP(C) to PrP(Sc) and probing into the pathogenesis of transmissible spongiform encephalopathy.

  1. An apolipoprotein B100 mimotope prevents obesity in mice

    PubMed Central

    Lee, Hee Jong; Choi, Jung Soon; Han, Jemin; Kim, Ji Young; Na, Hyun Kyun; Joung, Hae-Jung; Kim, Young Sik

    2015-01-01

    Although apolipoprotein B100 (ApoB100) plays a key role in peripheral fat deposition, it is not considered a suitable therapeutic target in obesity. In the present study we describe a novel ApoB100 mimotope, peptide pB1, and the use of pB1-based vaccine-like formulations (BVFs) against high-fat diet (HFD)-induced obesity. In HFD- compared with chow-fed adolescent mice, BVFs reduced the 3-month body-weight gains attributable to increased dietary fat by 44–65%, and prevented mesenteric fat accumulation and liver steatosis. The body-weight reductions paralleled the titres of pB1-reactive immunoglobulin G (IgG) antibodies, and pB1-reactive antibodies specifically recognized native ApoB100 and a synthetic peptide from the C-terminal half of ApoB100. In cultured 3T3L1 adipocytes, anti-pB1 antibodies increased lipolysis and inhibited low-density lipoprotein (LDL) uptake. In cultured RAW 264.7 macrophages, the same antibodies enhanced LDL uptake (without causing foam cell formation). These findings make ApoB100 a promising target for an immunization strategy against HFD-induced obesity. PMID:26519425

  2. Apolipoprotein A5: Extracellular and Intracellular Roles in Triglyceride Metabolism.

    PubMed

    Forte, Trudy M; Ryan, Robert O

    2015-01-01

    This review addresses two major functions of apolipoprotein (apo) A5 including (1) its role in maintaining normal plasma levels of circulating triglyceride (TG) and (2) its role as a component of hepatic lipid droplets. ApoA5 is synthesized solely in the liver and circulating concentrations are extremely low. In the plasma, ApoA5 associates with TG-rich lipoproteins and enhances TG hydrolysis and remnant lipoprotein clearance. ApoA5 loss-of-function single nucleotide polymorphisms are associated with reduced lipolysis, poor remnant clearance and concomitantly, hypertriglyceridemia. Although there have been substantial breakthroughs in understanding pathophysiology associated with secreted ApoA5, there is a paucity of knowledge on the functionality of intracellular ApoA5. However, recent studies indicate that overexpression of intracellular ApoA5 is positively associated with accumulation of TG-rich lipid droplets in hepatocytes. It is thought that ApoA5 may have a causal role in non-alcoholic fatty liver disease (NAFLD) and thus, may serve as a target for developing therapeutics for NAFLD.

  3. MicroRNAs regulating apolipoprotein B-containing lipoprotein production.

    PubMed

    Zhou, Liye; Irani, Sara; Sirwi, Alaa; Hussain, M Mahmood

    2016-12-01

    MicroRNAs (miRs) are small, non-coding RNAs that regulate gene expression and have been implicated in many pathological conditions. Significant progress has been made to unveil their role in lipid metabolism. This review aims at summarizing the role of different miRs that regulate hepatic assembly and secretion of apolipoprotein B (apoB)-containing lipoproteins. Overproduction and/or impaired clearance of these lipoproteins from circulation increase plasma concentrations of lipids enhancing risk for cardiovascular disease. So far, three miRs, miR-122, miR-34a, and miR-30c have been shown to modulate hepatic production of apoB-containing low density lipoproteins. In this review, we will first provide a brief overview of lipid metabolism and apoB-containing lipoprotein assembly to orient readers to different steps that have been shown to be regulated by miRs. Then, we will discuss the role of each miR on plasma lipids and atherosclerotic burden. Furthermore, we will summarize mechanistic studies explaining how these miRs regulate hepatic lipid synthesis, fatty acid oxidation, and lipoprotein secretion. Finally, we will briefly highlight the potential use of each miR as a therapeutic drug for treating cardiovascular diseases. This article is part of a Special Issue entitled: MicroRNAs and lipid/energy metabolism and related diseases edited by Carlos Fernández-Hernando and Yajaira Suárez.

  4. Apolipoprotein E and Alzheimer disease: risk, mechanisms, and therapy

    PubMed Central

    Liu, Chia-Chen; Kanekiyo, Takahisa; Xu, Huaxi; Bu, Guojun

    2013-01-01

    Apolipoprotein E (ApoE) is a major cholesterol carrier that supports lipid transport and injury repair in the brain. APOE polymorphic alleles are the main genetic determinants of Alzheimer disease (AD) risk: individuals carrying the ε4 allele are at increased risk of AD compared with those carrying the more common ε3 allele, whereas the ε2 allele decreases risk. Presence of the APOE ε4 allele is also associated with increased risk for cerebral amyloid angiopathy and age-related cognitive decline during normal ageing. ApoE–lipoproteins bind to several cell-surface receptors to deliver lipids and also to hydrophobic amyloid-β (Aβ) peptide, which is thought to initiate toxic events that lead to synaptic dysfunction and neurodegeneration in AD. ApoE isoforms differentially regulate Aβ aggregation and clearance in the brain, and have distinct functions in regulating brain lipid transport, glucose metabolism, neuronal signalling, neuroinflammation, and mitochondrial function. In this Review, we describe current knowledge on ApoE in the CNS, with a particular emphasis on the clinical and pathological features associated with carriers of different ApoE isoforms. We also discuss Aβ-dependent and Aβ-independent mechanisms that link ApoE4 status with AD risk, and consider how to design effective strategies for AD therapy by targeting ApoE. PMID:23296339

  5. Apolipoprotein D Internalization Is a Basigin-dependent Mechanism.

    PubMed

    Najyb, Ouafa; Brissette, Louise; Rassart, Eric

    2015-06-26

    Apolipoprotein D (apoD), a member of the lipocalin family, is a 29-kDa secreted glycoprotein that binds and transports small lipophilic molecules. Expressed in several tissues, apoD is up-regulated under different stress stimuli and in a variety of pathologies. Numerous studies have revealed that overexpression of apoD led to neuroprotection in various mouse models of acute stress and neurodegeneration. This multifunctional protein is internalized in several cells types, but the specific internalization mechanism remains unknown. In this study, we demonstrate that the internalization of apoD involves a specific cell surface receptor in 293T cells, identified as the transmembrane glycoprotein basigin (BSG, CD147); more particularly, its low glycosylated form. Our results show that internalized apoD colocalizes with BSG into vesicular compartments. Down-regulation of BSG disrupted the internalization of apoD in cells. In contrast, overexpression of basigin in SH-5YSY cells, which poorly express BSG, restored the uptake of apoD. Cyclophilin A, a known ligand of BSG, competitively reduced apoD internalization, confirming that BSG is a key player in the apoD internalization process. In summary, our results demonstrate that basigin is very likely the apoD receptor and provide additional clues on the mechanisms involved in apoD-mediated functions, including neuroprotection.

  6. Apolipoprotein E and Alzheimer disease: risk, mechanisms and therapy.

    PubMed

    Liu, Chia-Chen; Liu, Chia-Chan; Kanekiyo, Takahisa; Xu, Huaxi; Bu, Guojun

    2013-02-01

    Apolipoprotein E (Apo-E) is a major cholesterol carrier that supports lipid transport and injury repair in the brain. APOE polymorphic alleles are the main genetic determinants of Alzheimer disease (AD) risk: individuals carrying the ε4 allele are at increased risk of AD compared with those carrying the more common ε3 allele, whereas the ε2 allele decreases risk. Presence of the APOE ε4 allele is also associated with increased risk of cerebral amyloid angiopathy and age-related cognitive decline during normal ageing. Apo-E-lipoproteins bind to several cell-surface receptors to deliver lipids, and also to hydrophobic amyloid-β (Aβ) peptide, which is thought to initiate toxic events that lead to synaptic dysfunction and neurodegeneration in AD. Apo-E isoforms differentially regulate Aβ aggregation and clearance in the brain, and have distinct functions in regulating brain lipid transport, glucose metabolism, neuronal signalling, neuroinflammation, and mitochondrial function. In this Review, we describe current knowledge on Apo-E in the CNS, with a particular emphasis on the clinical and pathological features associated with carriers of different Apo-E isoforms. We also discuss Aβ-dependent and Aβ-independent mechanisms that link Apo-E4 status with AD risk, and consider how to design effective strategies for AD therapy by targeting Apo-E.

  7. Prenatal mercury exposure, neurodevelopment and apolipoprotein E genetic polymorphism.

    PubMed

    Snoj Tratnik, Janja; Falnoga, Ingrid; Trdin, Ajda; Mazej, Darja; Fajon, Vesna; Miklavčič, Ana; Kobal, Alfred B; Osredkar, Joško; Sešek Briški, Alenka; Krsnik, Mladen; Neubauer, David; Kodrič, Jana; Stropnik, Staša; Gosar, David; Lešnik Musek, Petra; Marc, Janja; Jurkovič Mlakar, Simona; Petrović, Oleg; Vlašić-Cicvarić, Inge; Prpić, Igor; Milardović, Ana; Radić Nišević, Jelena; Vuković, Danijela; Fišić, Elizabeta; Špirić, Zdravko; Horvat, Milena

    2017-01-01

    The aim of the present study was to evaluate the association between prenatal exposure to mercury (Hg) and neurodevelopment of the child, taking into account genetic polymorphism of apolipoprotein E (Apoe) and other relevant confounders. Six hundred and one mother-child pairs were recruited from the central Slovenia region and 243 from Rijeka, on the Croatian coast of the northern Adriatic. The total Hg in cord blood, Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) assessment at 18 months of age and Apoe genotyping was performed on 361 children; 237 of them were from Slovenia and 124 from Croatia. The results showed negative association between low-to-moderate Hg exposure in children with normal neurodevelopmental outcome and cognitive and fine motor scores at 18 months of age as assessed by Bayley III. The Hg-related decrease in cognitive score was observed only in children carrying at least one Apoe ε4 allele, while the decrease in fine motor scores was independent of the Apoe genotype. Adjusting for selenium (Se) and lead (Pb) levels, a positive association between Se and the language score and a negative association between Pb and the motor score was observed, but not in the subgroup of children carrying the ε4 allele.

  8. The Apolipoprotein L1 Gene and Cardiovascular Disease

    PubMed Central

    Robinson, Todd W.; Freedman, Barry I.

    2016-01-01

    Relative to those with European ancestry, African Americans have an excess incidence of nondiabetic chronic kidney disease predominantly due to two coding renal-risk variants in the apolipoprotein L1 gene (APOL1). This APOL1–kidney disease association is independent of systemic hypertension or blood pressure. Recent reports describe extra-renal effects of the APOL1 G1 and G2 renal-risk variants on cardiovascular disease (CVD), subclinical atherosclerosis, lipoprotein particle concentrations, and survival. However, results have been less consistent than those seen in kidney disease, and the observed APOL1 associations with CVD vary from risk to protective. This manuscript reviews the relationships between APOL1 renal-risk variants and CVD, with an emphasis on study-specific factors that may have contributed to disparate observations. It is possible that APOL1 renal-risk variants impact the systemic vasculature, not only the kidneys. As novel therapies for APOL1-associated nephropathy are developed, APOL1 variant protein effects on large blood vessels and risk of CVD will need to be considered. PMID:28298955

  9. Alzheimer's disease, apolipoprotein E and hormone replacement therapy.

    PubMed

    Depypere, H; Vierin, A; Weyers, S; Sieben, A

    2016-12-01

    Alzheimer's disease is the most frequent cause of dementia in older patients. The prevalence is higher in women than in men. This may be the result of both the higher life expectancy of women and the loss of neuroprotective estrogen after menopause. Earlier age at menopause (spontaneous or surgical) is associated with an enhanced risk of developing Alzheimer's disease. Therefore, it is postulated that estrogen could be protective against it. If so, increasing exposure to estrogen through the use of postmenopausal hormone replacement could also be protective against Alzheimer's disease. The results of the clinical studies that have examined this hypothesis are inconclusive, however. One explanation for this is that estrogen treatment is protective only if it is initiated in the years immediately after menopause. Another possibility is that the neuroprotective effects of estrogen are negated by a particular genotype of apolipoprotein E. This protein plays an important role in cholesterol transport to the neurons. Studies that have examined the link between estrogen replacement therapy, Alzheimer's disease and the E4 allele of ApoE are inconclusive. This article reviews the literature on the influence of hormone replacement therapy on the incidence and progression of Alzheimer's disease.

  10. Lineage-Specific Changes in Biomarkers in Great Apes and Humans

    PubMed Central

    Ronke, Claudius; Dannemann, Michael; Halbwax, Michel; Fischer, Anne; Helmschrodt, Christin; Brügel, Mathias; André, Claudine; Atencia, Rebeca; Mugisha, Lawrence; Scholz, Markus; Ceglarek, Uta; Thiery, Joachim; Pääbo, Svante; Prüfer, Kay; Kelso, Janet

    2015-01-01

    Although human biomedical and physiological information is readily available, such information for great apes is limited. We analyzed clinical chemical biomarkers in serum samples from 277 wild- and captive-born great apes and from 312 healthy human volunteers as well as from 20 rhesus macaques. For each individual, we determined a maximum of 33 markers of heart, liver, kidney, thyroid and pancreas function, hemoglobin and lipid metabolism and one marker of inflammation. We identified biomarkers that show differences between humans and the great apes in their average level or activity. Using the rhesus macaques as an outgroup, we identified human-specific differences in the levels of bilirubin, cholinesterase and lactate dehydrogenase, and bonobo-specific differences in the level of apolipoprotein A-I. For the remaining twenty-nine biomarkers there was no evidence for lineage-specific differences. In fact, we find that many biomarkers show differences between individuals of the same species in different environments. Of the four lineage-specific biomarkers, only bilirubin showed no differences between wild- and captive-born great apes. We show that the major factor explaining the human-specific difference in bilirubin levels may be genetic. There are human-specific changes in the sequence of the promoter and the protein-coding sequence of uridine diphosphoglucuronosyltransferase 1 (UGT1A1), the enzyme that transforms bilirubin and toxic plant compounds into water-soluble, excretable metabolites. Experimental evidence that UGT1A1 is down-regulated in the human liver suggests that changes in the promoter may be responsible for the human-specific increase in bilirubin. We speculate that since cooking reduces toxic plant compounds, consumption of cooked foods, which is specific to humans, may have resulted in relaxed constraint on UGT1A1 which has in turn led to higher serum levels of bilirubin in humans. PMID:26247603

  11. Lineage-Specific Changes in Biomarkers in Great Apes and Humans.

    PubMed

    Ronke, Claudius; Dannemann, Michael; Halbwax, Michel; Fischer, Anne; Helmschrodt, Christin; Brügel, Mathias; André, Claudine; Atencia, Rebeca; Mugisha, Lawrence; Scholz, Markus; Ceglarek, Uta; Thiery, Joachim; Pääbo, Svante; Prüfer, Kay; Kelso, Janet

    2015-01-01

    Although human biomedical and physiological information is readily available, such information for great apes is limited. We analyzed clinical chemical biomarkers in serum samples from 277 wild- and captive-born great apes and from 312 healthy human volunteers as well as from 20 rhesus macaques. For each individual, we determined a maximum of 33 markers of heart, liver, kidney, thyroid and pancreas function, hemoglobin and lipid metabolism and one marker of inflammation. We identified biomarkers that show differences between humans and the great apes in their average level or activity. Using the rhesus macaques as an outgroup, we identified human-specific differences in the levels of bilirubin, cholinesterase and lactate dehydrogenase, and bonobo-specific differences in the level of apolipoprotein A-I. For the remaining twenty-nine biomarkers there was no evidence for lineage-specific differences. In fact, we find that many biomarkers show differences between individuals of the same species in different environments. Of the four lineage-specific biomarkers, only bilirubin showed no differences between wild- and captive-born great apes. We show that the major factor explaining the human-specific difference in bilirubin levels may be genetic. There are human-specific changes in the sequence of the promoter and the protein-coding sequence of uridine diphosphoglucuronosyltransferase 1 (UGT1A1), the enzyme that transforms bilirubin and toxic plant compounds into water-soluble, excretable metabolites. Experimental evidence that UGT1A1 is down-regulated in the human liver suggests that changes in the promoter may be responsible for the human-specific increase in bilirubin. We speculate that since cooking reduces toxic plant compounds, consumption of cooked foods, which is specific to humans, may have resulted in relaxed constraint on UGT1A1 which has in turn led to higher serum levels of bilirubin in humans.

  12. Absolute parameters for AI Phoenicis using WASP photometry

    NASA Astrophysics Data System (ADS)

    Kirkby-Kent, J. A.; Maxted, P. F. L.; Serenelli, A. M.; Turner, O. D.; Evans, D. F.; Anderson, D. R.; Hellier, C.; West, R. G.

    2016-06-01

    Context. AI Phe is a double-lined, detached eclipsing binary, in which a K-type sub-giant star totally eclipses its main-sequence companion every 24.6 days. This configuration makes AI Phe ideal for testing stellar evolutionary models. Difficulties in obtaining a complete lightcurve mean the precision of existing radii measurements could be improved. Aims: Our aim is to improve the precision of the radius measurements for the stars in AI Phe using high-precision photometry from the Wide Angle Search for Planets (WASP), and use these improved radius measurements together with estimates of the masses, temperatures and composition of the stars to place constraints on the mixing length, helium abundance and age of the system. Methods: A best-fit ebop model is used to obtain lightcurve parameters, with their standard errors calculated using a prayer-bead algorithm. These were combined with previously published spectroscopic orbit results, to obtain masses and radii. A Bayesian method is used to estimate the age of the system for model grids with different mixing lengths and helium abundances. Results: The radii are found to be R1 = 1.835 ± 0.014 R⊙, R2 = 2.912 ± 0.014 R⊙ and the masses M1 = 1.1973 ± 0.0037 M⊙, M2 = 1.2473 ± 0.0039 M⊙. From the best-fit stellar models we infer a mixing length of 1.78, a helium abundance of YAI = 0.26 +0.02-0.01 and an age of 4.39 ± 0.32 Gyr. Times of primary minimum show the period of AI Phe is not constant. Currently, there are insufficient data to determine the cause of this variation. Conclusions: Improved precision in the masses and radii have improved the age estimate, and allowed the mixing length and helium abundance to be constrained. The eccentricity is now the largest source of uncertainty in calculating the masses. Further work is needed to characterise the orbit of AI Phe. Obtaining more binaries with parameters measured to a similar level of precision would allow us to test for relationships between helium

  13. [Serum apolipoprotein and lipoprotein levels in patients with diabetes mellitus type 2].

    PubMed

    Gosiewska, A; Zarzycki, W; Depta, K; Składanek, J; Kinalski, M; Lopaczyński, W

    1989-04-01

    Lipid disturbances were evaluated in type II diabetes comparing the results of determinations of total cholesterol and HDL-cholesterol with apolipoprotein A and B levels. The study was carried out in 32 diabetics with type II disease with mean duration 7 +/- 9 years, 15 males and 17 females, and in 30 controls. In all cases postprandial glycaemia, haemoglobin A1C, total cholesterol concentration (by the Liebermann-Burchardt method), HDL-cholesterol (by the Błaszczyszyn method), triglycerides (by the enzymatic method), an apolipoprotein A and B (by Mancini radial immunodiffusion method using a Bio-Merieux kit) were determined. A significant correlation was demonstrated between the concentrations of cholesterol and apolipoprotein A, on the one hand, and blood glucose level, on the other, and apolipoprotein A was found to be a better indicator of lipid disturbances in the aspect of diabetes control then apolipoprotein B. The latter was a better indicator of lipid disturbances in diabetes connected with obesity, than total cholesterol.

  14. A 10-bp deletion in the apolipoprotein epsilon gene causing apolipoprotein E deficiency and severe type III hyperlipoproteinemia.

    PubMed Central

    Feussner, G.; Dobmeyer, J.; Gröne, H. J.; Lohmer, S.; Wohlfeil, S.

    1996-01-01

    Type III hyperlipoproteinemia (HLP) is usually associated with homozygosity for apolipoprotein (apo) E2. We identified a 30-year-old male German of Hungarian ancestry with severe type III HLP and apo E deficiency. The disease was expressed in an extreme phenotype with multiple cutaneous xanthomas. Apo E was detectable only in trace amounts in plasma but not in the different lipoprotein fractions. Direct sequencing of PCR-amplified segments of the apo epsilon gene identified a 10-bp deletion in exon 4 (bp 4037-4046 coding for amino acids 209-212 of the mature protein). The mutation is predictive for a reading frameshift introducing a premature stop codon (TGA) at amino acid 229. By western blot analysis, we found small amounts of a truncated apo E in the patient's plasma. Family analysis revealed that the proband was homozygous--and 10 of 24 relatives were heterozygous--for the mutation. Heterozygotes had, as compared to unaffected family members, significantly higher triglycerides (TG), very low-density lipoprotein (VLDL) cholesterol and a significantly higher VLDL cholesterol-to-serum TG ratio, which is indicative of a delayed remnant catabolism. We propose that the absence of a functionally active apo E is the cause of the severe type III HLP in the patient and that the mutation, even in a single dose in heterozygotes, predisposes in variable severity to the phenotypic expression of the disease. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8571954

  15. Impact of apolipoprotein E genotype variation on means, variances, and correlations of plasma lipid, lipoprotein, and apolipoprotein traits in octogenarians

    SciTech Connect

    Haviland, M.B.; Sing, C.F.; Lussier-Cacan, S.; Davignon, J.

    1995-09-25

    The impact of apolipoprotein (apo) E genotype variation on means, variances and correlations between plasma lipid traits was studied in male and female octogenarians. Females had significantly higher mean levels of all 10 of the measured plasma lipid traits than males. The subset of concomitants (i.e., age, height, weight, body mass index, glucose and uric acid) that made a statistically significant contribution to interindividual variability was different in males and females for every trait considered. Gender-specific associations between variation in apo E genotype and variation in particular measures of lipid metabolism, adjusted for concomitant variation, were observed: in females there were no statistically significant associations while in males the means of the three common apo E genotypes were significantly different for adjusted measures of total cholesterol, low density lipoprotein cholesterol and low density lipoprotein-apo B. The common apo E genotypes were heterogeneous with respect to intragenotypic variance for adjusted log-transformed triglyceride levels in females only. Finally, the three common apo E genotypes were heterogeneous with respect to the correlation between traits, adjusted for concomitant variation, and gender influenced the manner in which the genotypes differed for specific correlations. This study documents that variation in the apo E gene has a significant impact on means, variances and correlations of plasma lipid traits in octogenarians, but the effects are context-, that is, gender- and age-, dependent. 65 refs., 4 figs., 3 tabs.

  16. Apolipoprotein E4 Elicits Lysosomal Cathepsin D Release, Decreased Thioredoxin-1 Levels, and Apoptosis

    PubMed Central

    Persson, Torbjörn; Lattanzio, Francesca; Calvo-Garrido, Javier; Rimondini, Roberto; Rubio-Rodrigo, Marta; Sundström, Erik; Maioli, Silvia; Sandebring-Matton, Anna; Cedazo-Mínguez, Ángel

    2016-01-01

    The major genetic risk factor for Alzheimer’s disease (AD), apolipoprotein E4 (ApoE4), has been suggested to have detrimental effects on neurons, including direct toxicity via apoptosis. Thioredoxin-1 (Trx1) is an endogenous antioxidant protein important for redox regulation and participates in the regulation of apoptosis through the inhibition of apoptosis signal-regulating kinase-1 (Ask-1). In this study, we have investigated the effects of ApoE on Trx1 in the brain. Our results showed that the protein levels of Trx1 were reduced in the hippocampus of ApoE4 targeted replacement (TR) mice compared to ApoE3 TR mice. The reduction was also seen in vitro after treatment of both human primary cortical neurons and neuroblastoma cells with human recombinant ApoE4 (rApoE4). Furthermore, ApoE4 caused a disruption of lysosomal integrity and a shift in the localization of Cathepsin D, an enzyme known to degrade Trx1. ApoE4 treatment induced in addition apoptosis through translocation of Death-domain associated protein-6 (Daxx) from the nucleus to the cytosol, suggesting an activation of the Ask-1 pathway. This toxicity was prevented by overexpression of Trx1 and other endogenous Ask-1 inhibitors. Our data suggests that down-regulation of Trx1 is involved in the toxicity caused by ApoE4. An activated ASK-1 pathway might indeed make cells more vulnerable to other insults such as amyloid-β, which could partially explain the mechanism behind the strongest genetic risk factor for AD. PMID:28035917

  17. Cognitive deficits and disruption of neurogenesis in a mouse model of apolipoprotein E4 domain interaction.

    PubMed

    Adeosun, Samuel O; Hou, Xu; Zheng, Baoying; Stockmeier, Craig; Ou, Xiaoming; Paul, Ian; Mosley, Thomas; Weisgraber, Karl; Wang, Jun Ming

    2014-01-31

    Apolipoprotein E4 (apoE4) allele is the major genetic risk factor for sporadic Alzheimer disease (AD) due to the higher prevalence and earlier onset of AD in apoE4 carriers. Accumulating data suggest that the interaction between the N- and the C-terminal domains in the protein may be the main pathologic feature of apoE4. To test this hypothesis, we used Arg-61 mice, a model of apoE4 domain interaction, by introducing the domain interaction feature of human apoE4 into native mouse apoE. We carried out hippocampus-dependent learning and memory tests and related cellular and molecular assays on 12- and 3-month-old Arg-61 and age-matched background C57BL/6J mice. Learning and memory task performance were impaired in Arg-61 mice at both old and young ages compared with C57BL/6J mice. Surprisingly, young Arg-61 mice had more mitotic doublecortin-positive cells in the subgranular zone; mRNA levels of brain-derived neurotrophic factor (BDNF) and TrkB were also higher in 3-month-old Arg-61 hippocampus compared with C57BL/6J mice. These early-age neurotrophic and neurogenic (proliferative) effects in the Arg-61 mouse may be an inadequate compensatory but eventually detrimental attempt by the system to "repair" itself. This is supported by the higher cleaved caspase-3 levels in the young animals that not only persisted, but increased in old age, and the lower levels of doublecortin at old age in the hippocampus of Arg-61 mice. These results are consistent with human apoE4-dependent cognitive and neuro-pathologic changes, supporting the principal role of domain interaction in the pathologic effect of apoE4. Domain interaction is, therefore, a viable therapeutic/prophylactic target for cognitive impairment and AD in apoE4 subjects.

  18. QML-AiNet: An immune network approach to learning qualitative differential equation models.

    PubMed

    Pang, Wei; Coghill, George M

    2015-02-01

    In this paper, we explore the application of Opt-AiNet, an immune network approach for search and optimisation problems, to learning qualitative models in the form of qualitative differential equations. The Opt-AiNet algorithm is adapted to qualitative model learning problems, resulting in the proposed system QML-AiNet. The potential of QML-AiNet to address the scalability and multimodal search space issues of qualitative model learning has been investigated. More importantly, to further improve the efficiency of QML-AiNet, we also modify the mutation operator according to the features of discrete qualitative model space. Experimental results show that the performance of QML-AiNet is comparable to QML-CLONALG, a QML system using the clonal selection algorithm (CLONALG). More importantly, QML-AiNet with the modified mutation operator can significantly improve the scalability of QML and is much more efficient than QML-CLONALG.

  19. QML-AiNet: An immune network approach to learning qualitative differential equation models

    PubMed Central

    Pang, Wei; Coghill, George M.

    2015-01-01

    In this paper, we explore the application of Opt-AiNet, an immune network approach for search and optimisation problems, to learning qualitative models in the form of qualitative differential equations. The Opt-AiNet algorithm is adapted to qualitative model learning problems, resulting in the proposed system QML-AiNet. The potential of QML-AiNet to address the scalability and multimodal search space issues of qualitative model learning has been investigated. More importantly, to further improve the efficiency of QML-AiNet, we also modify the mutation operator according to the features of discrete qualitative model space. Experimental results show that the performance of QML-AiNet is comparable to QML-CLONALG, a QML system using the clonal selection algorithm (CLONALG). More importantly, QML-AiNet with the modified mutation operator can significantly improve the scalability of QML and is much more efficient than QML-CLONALG. PMID:25648212

  20. Apolipoprotein A1 in channel catfish: Transcriptional analysis, antimicrobial activity, and efficacy as plasmid DNA immunostimulant against Aeromonas hydrophila infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to: 1) determine transcriptional profiles of apolipoprotein A1 (ApoA1) in collected channel catfish tissues after infection with A. hydrophila by bath immersion; 2) investigate whether recombinant channel catfish apolipoprotein A1 produced in E. coli expression syst...

  1. High-density lipoprotein 3 physicochemical modifications induced by interaction with human polymorphonuclear leucocytes affect their ability to remove cholesterol from cells.

    PubMed Central

    Cogny, A; Atger, V; Paul, J L; Soni, T; Moatti, N

    1996-01-01

    1. We have recently reported that a short incubation (60 min) in vitro of high-density lipoprotein (HDL) 3 with human polymorphonuclear leucocytes (PMNs) leads to a proteolytic cleavage of apolipoprotein (apo) AII and to a change in the distribution of apo AI isoforms [Cogny, Paul, Atger, Soni and Moatti (1994) Eur. J. Biochem. 222, 965-973]. Since PMNs have been observed to be present in the earliest atherosclerotic lesions for a number of days, we investigated the HDL3 physiochemical modifications induced by in vitro interaction for a long period of time (24 h) with PMNs and the consequences of the changes on the ability of HDL3 to remove cholesterol from cells. 2. The stimulated PMN modification of HDL3 over 24 h resulted in a partial loss of protein with no variation in lipid molar ratio and a loss of 50% of HDL alpha-tocopherol content. The decrease in total protein was due first to a complete degradation of apo AII, and secondly to a partial loss of apo AI. The apo AI remaining on the particles was in part hydrolysed and the apo AI-1 isoform was completely shifted to the apo AI-2 isoform. These apo changes were accompanied by a displacement of the native HDL3 apparent size toward predominantly larger particles. 3. The ability of PMN-modified HDL3 to remove 3H-labelled free cholesterol from cells was measured in two cell lines: Fu5AH rat hepatoma cells and J774 mouse macrophages. HDL3 which had only a limited contact with PMNs (60 min) showed only a small non-significant reduction in the efficiency of cholesterol efflux. On the other hand, compared with native HDL3, HDL3 modified by PMNs for 24 h had a markedly reduced ability to remove cholesterol from cells, regardless of the type of cell. 4. The results suggest that PMN-modified HDL3, if occurring in vivo, could contribute to acceleration of the atherogenic process by decreasing the cholesterol efflux from cells. PMID:8660296

  2. Transgenic rabbit that expresses a functional human lipoprotein (a)

    DOEpatents

    Rouy, Didier; Duverger, Nicolas; Emmanuel, Florence; Denefle, Patrice; Houdebine, Louis-Marie; Viglietta, Celine; Rubin, Edward M.; Hughes, Steven D.

    2003-01-01

    A transgenic rabbit which has in its genomic DNA sequences that encode apolipoprotein (a) and apolipoprotein B polypeptides which are capable of combining to produce lipoprotein (a), a process for creating such a rabbit, and the use of the rabbit to identify compounds which are effective in the treatment of human diseases which are associated with, induced and/or exacerbated by Lp(a) expression.

  3. Insulin resistance, dyslipidemia, and apolipoprotein E interactions as mechanisms in cognitive impairment and Alzheimer's disease

    PubMed Central

    Salameh, Therese S; Rhea, Elizabeth M; Hanson, Angela J

    2016-01-01

    An increased risk for Alzheimer's disease is associated with dyslipidemia and insulin resistance. A separate literature shows the genetic risk for developing Alzheimer's disease is strongly correlated to the presence of the E4 isoform of the apolipoprotein E carrier protein. Understanding how apolipoprotein E carrier protein, lipids, amyloid β peptides, glucose, central nervous system insulin, and peripheral insulin interact with one another in Alzheimer's disease is an area of increasing interest. Here, we will review the evidence relating apolipoprotein E carrier protein, lipids, and insulin action to Alzheimer's disease and Aβ peptides and then propose mechanisms as to how these factors might interact with one another to impair cognition and promote Alzheimer's disease. PMID:27470930

  4. AI's Philosophical Underpinnings: A Thinking Person's Walk through the Twists and Turns of Artificial Intelligence's Meandering Path

    NASA Technical Reports Server (NTRS)

    Colombano, Silvano; Norvig, Peter (Technical Monitor)

    2000-01-01

    Few human endeavors can be viewed both as extremely successful and unsuccessful at the same time. This is typically the case when goals have not been well defined or have been shifting in time. This has certainly been true of Artificial Intelligence (AI). The nature of intelligence has been the object of much thought and speculation throughout the history of philosophy. It is in the nature of philosophy that real headway is sometimes made only when appropriate tools become available. Similarly the computer, coupled with the ability to program (at least in principle) any function, appeared to be the tool that could tackle the notion of intelligence. To suit the tool, the problem of the nature of intelligence was soon sidestepped in favor of this notion: If a probing conversation with a computer could not be distinguished from a conversation with a human, then AI had been achieved. This notion became known as the Turing test, after the mathematician Alan Turing who proposed it in 1950. Conceptually rich and interesting, these early efforts gave rise to a large portion of the field's framework. Key to AI, rather than the 'number crunching' typical of computers until then, was viewed as the ability to manipulate symbols and make logical inferences. To facilitate these tasks, AI languages such as LISP and Prolog were invented and used widely in the field. One idea that emerged and enabled some success with real world problems was the notion that 'most intelligence' really resided in knowledge. A phrase attributed to Feigenbaum, one of the pioneers, was 'knowledge is the power.' With this premise, the problem is shifted from 'how do we solve problems' to 'how do we represent knowledge.' A good knowledge representation scheme could allow one to draw conclusions from given premises. Such schemes took forms such as rules,frames and scripts. It allowed the building of what became known as expert systems or knowledge based systems (KBS).

  5. Plasma Apolipoprotein A1 as a Biomarker for Parkinson's Disease

    PubMed Central

    Qiang, Judy K.; Wong, Yvette C.; Siderowf, Andrew; Hurtig, Howard I.; Xie, Sharon X.; Lee, Virginia M.-Y.; Trojanowski, John Q.; Yearout, Dora; Leverenz, James; Montine, Thomas J.; Stern, Matt; Mendick, Susan; Jennings, Danna; Zabetian, Cyrus; Marek, Ken; Chen-Plotkin, Alice S.

    2013-01-01

    Objective To identify plasma-based biomarkers for Parkinson's Disease (PD) risk. Methods In a discovery cohort of 152 PD patients, plasma levels of 96 proteins were measured by multiplex immunoassay; proteins associated with age at PD onset were identified by linear regression. Findings from discovery screening were then assessed in a second cohort of 187 PD patients, using a different technique. Finally, in a third cohort of at-risk, asymptomatic individuals enrolled in the Parkinson's Associated Risk Study (PARS, n=134), plasma levels of the top candidate biomarker were measured, and dopamine transporter (DAT) imaging performed, to evaluate the association of plasma protein levels with dopaminergic system integrity. Results One of the best candidate protein biomarkers to emerge from discovery screening was apolipoprotein A1 (ApoA1, p=0.001). Low levels of ApoA1 correlated with earlier PD onset, with a 26% decrease in risk of developing PD associated with each tertile increase in ApoA1 (Cox proportional hazards p<0.001, hazard ratio=0.742). The association between plasma ApoA1 levels and age at PD onset replicated in an independent cohort of PD patients (p<0.001). Finally, in the PARS cohort of high-risk, asymptomatic subjects, lower plasma levels of ApoA1 were associated with greater putaminal DAT deficit (p=0.037). Interpretation Lower ApoA1 levels correlate with dopaminergic system vulnerability in symptomatic PD patients and in asymptomatic individuals with physiological reductions in dopamine transporter density consistent with prodromal PD. Plasma ApoA1 may be a new biomarker for PD risk. PMID:23447138

  6. Thyroid hormones upregulate apolipoprotein E gene expression in astrocytes.

    PubMed

    Roman, Corina; Fuior, Elena V; Trusca, Violeta G; Kardassis, Dimitris; Simionescu, Maya; Gafencu, Anca V

    Apolipoprotein E (apoE), a protein mainly involved in lipid metabolism, is associated with several neurodegenerative disorders including Alzheimer's disease. Despite numerous attempts to elucidate apoE gene regulation in the brain, the exact mechanism is still uncovered. The mechanism of apoE gene regulation in the brain involves the proximal promoter and multienhancers ME.1 and ME.2, which evolved by gene duplication. Herein we questioned whether thyroid hormones and their nuclear receptors have a role in apoE gene regulation in astrocytes. Our data showed that thyroid hormones increase apoE gene expression in HTB14 astrocytes in a dose-dependent manner. This effect can be intermediated by the thyroid receptor β (TRβ) which is expressed in these cells. In the presence of triiodothyronine (T3) and 9-cis retinoic acid, in astrocytes transfected to overexpress TRβ and retinoid X receptor α (RXRα), apoE promoter was indirectly activated through the interaction with ME.2. To determine the location of TRβ/RXRα binding site on ME.2, we performed DNA pull down assays and found that TRβ/RXRα complex bound to the region 341-488 of ME.2. This result was confirmed by transient transfection experiments in which a series of 5'- and 3'-deletion mutants of ME.2 were used. These data support the existence of a biologically active TRβ binding site starting at 409 in ME.2. In conclusion, our data revealed that ligand-activated TRβ/RXRα heterodimers bind with high efficiency on tissue-specific distal regulatory element ME.2 and thus modulate apoE gene expression in the brain.

  7. Apolipoprotein E and its role in aging and survival.

    PubMed

    Bonomini, Francesca; Filippini, Francesca; Hayek, Tony; Aviram, Michael; Keidar, Shlomo; Rodella, Luigi F; Coleman, Raymond; Rezzani, Rita

    2010-02-01

    The study of biological aging has seen spectacular progress in the last decade and markers are increasingly employed for understanding physiological processes that change with age. Recently, it has been demonstrated that apolipoprotein E (apoE) has a major impact on longevity, but its mechanisms are still not fully understood. ApoE-deficient (E(o)) mice have proved to be a very popular model for studying spontaneous hypercholesterolemia and the subsequent development of atherosclerotic lesions, but only limited data are available with regard to aging and aging changes. We used this murine model to better characterize the involvement of apoE in aging and to evaluate its role in the maintenance of normal organ morphology. Our results show that E(0) mice at different ages (6, 12, 20 weeks old) developed age-dependent morphological and biochemical alterations, including fibrosis (newly formed collagen), pro-inflammatory cytokine (IL-6 and iNOS), lipofuscin accumulation, and decrease of antioxidant enzymes (superoxide dismutase and catalase) in several organs (kidney, liver and heart). It is significant that the observed degenerative findings in E(0) mice at different ages (6, 12, 20 weeks old) were not identified in control mice (C57BL), at 6, 12 and 20 weeks of age. Consequently, since these mice showed enzymatic and structural alterations, normally linked to the age, such as increase of lipofuscin, pro-inflammatory cytokines and decrease of antioxidant enzymes, we can conclude that apoE is a useful player in studies of longevity and age-related diseases, such as inflammatory status and atherosclerosis that are known risk factors for functional decline and early mortality. Moreover, it is possible that apoE may also play a role in other pathological conditions including, for example, cancer, rheumatoid arthritis and macular degeneration.

  8. Isoliquiritigenin Attenuates Atherogenesis in Apolipoprotein E-Deficient Mice

    PubMed Central

    Du, Fen; Gesang, Quzhen; Cao, Jia; Qian, Mei; Ma, Li; Wu, Dongfang; Yu, Hong

    2016-01-01

    Isoliquiritigenin (ISL) exhibits antioxidation and anti-inflammation activity. We sought to investigate the effects and mechanism of ISL on the development of atherosclerotic lesions in apolipoprotein E-deficient (apoE−/−) mice. Firstly, we determined that ISL reduced the mRNA levels of inflammatory factors interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and monocyte chemotactic protein-1 (MCP-1), while it increased the expression of several lipoprotein-related genes in peritoneal macrophages treated with lipopolysaccharide (LPS). ISL also enhanced peroxisome proliferator-activated receptor gamma (PPARγ) protein levels and reversed the changes of ATP-binding cassette transporter A (ABCA1) and cluster of differentiation 36 (CD36) in macrophages treated with oxidative low-density lipoprotein (ox-LDL). Then, in an in vivo study, female apoE−/− mice were fed a Western diet with ISL (0, 20, 100 mg/kg/day) added for 12 weeks. We found that ISL decreased the plasma cholesterol levels of very low-density lipoprotein (VLDL)/LDL, promoted plasma superoxide dismutase (SOD) and paraoxonase-1 (PON1) activities, and decreased plasma IL-6, TNF-α, and MCP-1 levels. Moreover, ISL significantly reduced the atherosclerotic lesions and hepatic steatosis in apoE−/− mice. In the liver, ISL altered the expression of several key genes (such as SRBI, ABCA1, ABCG8, PPARγ, and FASN) involving cholesterol-selective uptake and excretion into bile, triglyceride (TG) biosynthesis, and inflammation. These results suggest that the atheroprotective effects of ISL are due to the improvement of lipid metabolism, antioxidation, and anti-inflammation, which involve PPARγ-dependent signaling. PMID:27869741

  9. Does Apolipoprotein E Genotype Increase Risk of Postoperative Delirium?

    PubMed Central

    Vasunilashorn, Sarinnapha; Ngo, Long; Kosar, Cyrus M.; Fong, Tamara G.; Jones, Richard N.

    2015-01-01

    Objectives To determine whether Apolipoprotein E (ApoE) is associated with postoperative delirium incidence, severity, and duration in older patients free of dementia at baseline. Design, Setting, Participants We examined 557 non-demented patients age ≥70 undergoing major non-cardiac surgery enrolled in the Successful Aging after Elective Surgery (SAGES) Study. Measurements We considered three ApoE measures: ε2, ε4 carriers vs. non-carriers, and a three-category ApoE measure. Delirium was determined using the Confusion Assessment Method (CAM) and chart review. We used generalized linear models to estimate the association between ApoE and delirium incidence, severity (peak CAM Severity [CAM-S] score), and days. Results ApoE ε2 and ε4 was present in 15% and 19% respectively, and postoperative delirium occurred in 24%. Among patients with delirium, the mean peak CAM-S score was 8.0 (standard deviation 4), with most patients experiencing one or two delirium days (51% or 28%, respectively). After adjusting for age, sex, surgical procedure, and preoperative cognitive function, ApoE ε4 and ε2 carrier status were not associated with postoperative delirium: RR for ε4=1.0, 95% confidence interval (CI) 0.7-1.5 and RR for ε2=0.9, 95% CI 0.6-1.4. No association between ApoE and delirium severity or number of delirium days was observed. Conclusions In older surgery patients free of dementia, our findings do not support the hypothesis that the ApoE genotype does not confer either risk or protection in postoperative delirium incidence, severity, or duration. Thus, an important genetic risk factor for Alzheimer's Disease does not affect risk of delirium. PMID:26238230

  10. Pavlovian, Skinner, and Other Behaviourists' Contributions to AI. Chapter 9

    NASA Technical Reports Server (NTRS)

    Kosinski, Withold; Zaczek-Chrzanowska, Dominika

    2007-01-01

    A version of the definition of intelligent behaviour will be supplied in the context of real and artificial systems. Short presentation of principles of learning, starting with Pavlovian s classical conditioning through reinforced response and operant conditioning of Thorndike and Skinner and finishing with cognitive learning of Tolman and Bandura will be given. The most important figures within behaviourism, especially those with contribution to AI, will be described. Some tools of artificial intelligence that act according to those principles will be presented. An attempt will be made to show when some simple rules for behaviour modifications can lead to a complex intelligent behaviour.

  11. An AIS-Based E-mail Classification Method

    NASA Astrophysics Data System (ADS)

    Qing, Jinjian; Mao, Ruilong; Bie, Rongfang; Gao, Xiao-Zhi

    This paper proposes a new e-mail classification method based on the Artificial Immune System (AIS), which is endowed with good diversity and self-adaptive ability by using the immune learning, immune memory, and immune recognition. In our method, the features of spam and non-spam extracted from the training sets are combined together, and the number of false positives (non-spam messages that are incorrectly classified as spam) can be reduced. The experimental results demonstrate that this method is effective in reducing the false rate.

  12. AiResearch QCGAT engine, airplane, and nacelle design features

    NASA Technical Reports Server (NTRS)

    Heldenbrand, R. W.

    1980-01-01

    The quiet, clean, general aviation turbofan engine and nacelle system was designed and tested. The engine utilized the core of the AiResearch model TFE731-3 engine and incorporated several unique noise- and emissions-reduction features. Components that were successfully adapted to this core include the fan, gearbox, combustor, low-pressure turbine, and associated structure. A highly versatile workhorse nacelle incorporating interchangeable acoustic and hardwall duct liners, showed that large-engine attenuation technology could be applied to small propulsion engines. The application of the mixer compound nozzle demonstrated both performance and noise advantages on the engine. Major performance, emissions, and noise goals were demonstrated.

  13. Urban, Forest, and Agricultural AIS Data: Fine Spectral Structure

    NASA Technical Reports Server (NTRS)

    Vanderbilt, V. C.

    1985-01-01

    Spectra acquired by the Airborne Imaging Spectrometer (AIS) near Lafayette, IN, Ely, MN, and over the Stanford University campus, CA were analyzed for fine spectral structure using two techniques: the ratio of radiance of a ground target to the radiance of a standard and also the correlation coefficient of radiances at adjacent wavelengths. The results show ramp like features in the ratios. These features are due to the biochemical composition of the leaf and to the optical scattering properties of its cuticle. The size and shape of the ramps vary with ground cover.

  14. Human intestinal lipoproteins. Studies in chyluric subjects.

    PubMed

    Green, P H; Glickman, R M; Saudek, C D; Blum, C B; Tall, A R

    1979-07-01

    To explore the role of the human intestine as a source of apolipoproteins, we have studied intestinal lipoproteins and apoprotein secretion in two subjects with chyluria (mesenteric lymphatic-urinary fistulae). After oral corn oil, apolipoprotein A-I (apoA-I) and apolipoprotein A-II (apoA-II) output in urine increased in parallel to urinary triglyceride. One subject, on two occasions, after 40 g of corn oil, excreted 8.4 and 8.6 g of triglyceride together with 196 and 199 mg apoA-I and on one occasion, 56 mg apoA-II. The other subject, after 40 g corn oil, excreted 0.3 g triglyceride and 17.5 mg apoA-I, and, after 100 g of corn oil, excreted 44.8 mg apoA-I and 5.8 mg apoA-II. 14.5+/-2.1% of apoA-I and 17.7+/-4.3% of apoA-II in chylous urine was in the d < 1.006 fraction (chylomicrons and very low density lipoprotein). Calculations based on the amount of apoA-I and apoA-II excreted on triglyceride-rich lipoproteins revealed that for these lipid loads, intestinal secretion could account for 50 and 33% of the calculated daily synthetic rate of apoA-I and apoA-II, respectively. Similarly, subject 2 excreted 48-70% and 14% of the calculated daily synthetic rate of apoA-I and apoA-II, respectively. Chylous urine contained chylomicrons, very low density lipoproteins and high density lipoproteins, all of which contained apoA-I. Chylomicrons and very low density lipoproteins contained a previously unreported human apoprotein of 46,000 mol wt. We have called this apoprotein apoA-IV because of the similarity of its molecular weight and amino acid composition to rat apoA-IV. In sodium dodecyl sulfate gels, chylomicron apoproteins consisted of apoB 3.4+/-0.7%, apoA-IV 10.0+/-3.3%, apoE 4.4+/-0.3%, apoA-I 15.0+/-1.8%, and apoC and apoA-II 43.3+/-11.3%. Very low density lipoprotein contained more apoB and apoA-IV and less apoC than chylomicrons. Ouchterlony immunodiffusion of chylomicron apoproteins revealed the presence of apoC-I, apoC-II, and apoC-III. In contrast, plasma

  15. Apolipoprotein B100 is required for hepatitis C infectivity and Mipomersen inhibits hepatitis C

    PubMed Central

    Schaefer, Esperance A K; Meixiong, James; Mark, Christina; Deik, Amy; Motola, Daniel L; Fusco, Dahlene; Yang, Andrew; Brisac, Cynthia; Salloum, Shadi; Lin, Wenyu; Clish, Clary B; Peng, Lee F; Chung, Raymond T

    2016-01-01

    AIM To characterize the role of apolipoprotein B100 (apoB100) in hepatitis C viral (HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases (TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDA-approved antisense inhibitor of apoB100, on HCV using in vitro cell-culture competent HCV and determined its impact on viral infectivity with the TCID50 method. RESULTS We found that apoB100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALEN-mediated gene deletion of apoB (APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apoB did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wild-type virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION ApoB is required for the generation of fully infectious HCV virions, and inhibition of apoB with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV. PMID:28018102

  16. AN APOLIPOPROTEIN E4 FRAGMENT CAN PROMOTE INTRACELLULAR ACCUMULATION OF AMYLOID PEPTIDE BETA 42

    PubMed Central

    Dafnis, Ioannis; Stratikos, Efstratios; Tzinia, Athina; Tsilibary, Effie C.; Zannis, Vassilis I.; Chroni, Angeliki

    2010-01-01

    Apolipoprotein E (apoE) plays a crucial role in lipid transport in circulation and the brain. The apoE4 isoform is a major risk factor for Alzheimer's disease (AD). ApoE4 is more susceptible to proteolysis than other apoE isoforms and apoE4 fragments have been found in brains of AD patients. These apoE4 fragments have been hypothesized to be involved in the pathogenesis of AD, although the mechanism is not clear. In this study we examined the effect of lipid-free apoE4 on amyloid precursor protein (APP) processing and Aβ40 and Aβ42 levels in human neuroblastoma SK-N-SH cells. We discovered that a specific apoE4 fragment, apoE4[Δ(166-299)], can promote the cellular uptake of extracellular Aβ40 and Aβ42 either generated after APP transfection or added exogenously. A longer length fragment, apoE4[Δ(186-299)], or full-length apoE4 failed to elicit this effect. ApoE4[Δ(166-299)] effected a 20% reduction of cellular sphingomyelin levels, as well as changes in cellular membrane micro-fluidity. Following uptake, approximately 50% of Aβ42 remained within the cell for at least 24h, and led to increased formation of reactive oxygen species. Overall, our findings suggest a direct link between two early events in the pathogenesis of AD, apoE4 proteolysis and intraneuronal presence of Aβ. PMID:20412390

  17. Apolipoprotein E forms stable complexes with recombinant Alzheimer's disease beta-amyloid precursor protein.

    PubMed Central

    Haas, C; Cazorla, P; Miguel, C D; Valdivieso, F; Vázquez, J

    1997-01-01

    Apolipoprotein E (apoE), a protein genetically linked to the incidence of Alzheimer's disease, forms SDS-stable complexes in vitro with beta-amyloid peptide (Abeta), the primary component of senile plaques. In the present study, we investigated whether apoE was able to bind full-length Abeta precursor protein (APP). Using a maltose-binding-protein-APP fusion protein and human very-low-density lipoprotein (VLDL), we detected an interaction of apoE with APP that was inhibited by Abeta or anti-apoE antibody. Saturation-binding experiments indicated a single binding equilibrium with an apparent 1:1 stoichiometry and a dissociation constant of 15 nM. An interaction was also observed using apoE from cerebrospinal fluid or delipidated VLDL, as well as recombinant apoE. APP.apoE complexes were SDS-stable, and their formation was not inhibited by reducing conditions; however, they were dissociated by SDS under reducing conditions. ApoE.APP complexes formed high-molecular-mass aggregates, and competition experiments suggested that amino acids 14-23 of Abeta are responsible for complex-formation. Finally, no differences were found when studying the interaction of APP with apoE3 or apoE4. Taken together, our results demonstrate that apoE may form stable complexes with the Abeta moiety of APP with characteristics similar to those of complexes formed with isolated Abeta, and suggest the intriguing possibility that apoE-APP interactions may be pathologically relevant in vivo. PMID:9224643

  18. Xyloketal B Attenuates Atherosclerotic Plaque Formation and Endothelial Dysfunction in Apolipoprotein E Deficient Mice

    PubMed Central

    Zhao, Li-Yan; Li, Jie; Yuan, Feng; Li, Mei; Zhang, Quan; Huang, Yun-Ying; Pang, Ji-Yan; Zhang, Bin; Sun, Fang-Yun; Sun, Hong-Shuo; Li, Qian; Cao, Lu; Xie, Yu; Lin, Yong-Cheng; Liu, Jie; Tan, Hong-Mei; Wang, Guan-Lei

    2015-01-01

    Our previous studies demonstrated that xyloketal B, a novel marine compound with a unique chemical structure, has strong antioxidant actions and can protect against endothelial injury in different cell types cultured in vitro and model organisms in vivo. The oxidative endothelial dysfunction and decrease in nitric oxide (NO) bioavailability are critical for the development of atherosclerotic lesion. We thus examined whether xyloketal B had an influence on the atherosclerotic plaque area in apolipoprotein E-deficient (apoE−/−) mice fed a high-fat diet and investigated the underlying mechanisms. We found in our present study that the administration of xyloketal B dose-dependently decreased the atherosclerotic plaque area both in the aortic sinus and throughout the aorta in apoE−/− mice fed a high-fat diet. In addition, xyloketal B markedly reduced the levels of vascular oxidative stress, as well as improving the impaired endothelium integrity and NO-dependent aortic vasorelaxation in atherosclerotic mice. Moreover, xyloketal B significantly changed the phosphorylation levels of endothelial nitric oxide synthase (eNOS) and Akt without altering the expression of total eNOS and Akt in cultured human umbilical vein endothelial cells (HUVECs). Here, it increased eNOS phosphorylation at the positive regulatory site of Ser-1177, while inhibiting phosphorylation at the negative regulatory site of Thr-495. Taken together, these findings indicate that xyloketal B has dramatic anti-atherosclerotic effects in vivo, which is partly due to its antioxidant features and/or improvement of endothelial function. PMID:25874925

  19. Radiative-SPR platform for the detection of apolipoprotein E for use in medical diagnostics

    NASA Astrophysics Data System (ADS)

    Sciacca, Beniamino; Francois, Alexandre; Penno, Megan A. S.; Brazzatti, Julie A.; Klingler-Hoffmann, Manuela; Hoffmann, Peter; Monro, Tanya M.

    2012-03-01

    Surface Plasmon Resonance (SPR) based sensors enable the rapid, label-free and highly sensitive detection of a large range of biomolecules. We have previously shown that, using silver coated optical fibres with an high surface roughness, a re-scattering of the surface plasmons is possible, turning SPR into a radiative process. This approach overcomes limitations associated with current SPR technologies such as the tight tolerance on the metallic coating thickness, and results in a more compact, versatile, robust and cost-effective approach. However, the specific detection of small molecules is a challenge in SPR systems, regardless of the SPR architecture that is used. This new sensing platform, which has proved effective for the detection of large molecules such as viruses, is now demonstrated to be able to detect small proteins thanks to an improved surface functionalization procedure, a key point for reliable and robust immunosensors. Avidin, a tetrameric biotin-binding protein, was used to link biotinylated antibodies to the biotinylated surface, with a given orientation, to enable efficient sensing of the analyte. This approach may offer significant advantages compared to protein A surface functionalization strategies such as a limited cross reactivity with free IgG antibodies in clinical samples. We demonstrate that by bringing together this novel emission-based fibre SPR platform, with an improved surface functionalization process, is possible to rapidly and specifically detect human apolipoprotein E, a low molecular weight protein (~39kDa) known to be involved in cardiovascular diseases, in Alzheimer's disease and in gastric cancer. The results obtained clearly show that this new sensing platform has the potential to serve as a tool for point-of-decision medical diagnostics.

  20. Beta-amyloid protein-containing inclusions in skeletal muscle of apolipoprotein-E-deficient mice.

    PubMed Central

    Robertson, T. A.; Dutton, N. S.; Martins, R. N.; Roses, A. D.; Kakulas, B. A.; Papadimitriou, J. M.

    1997-01-01

    The tibialis anterior muscle and soleus muscle of apolipoprotein-E-deficient mice were examined by light and electron microscopy. By light microscopy, sarcoplasmic inclusions were seen in tibialis anterior muscle and 40% of type 2 myofibers were affected in all animals over 8 months of age. These inclusions reacted for nonspecific esterase, cytochrome oxidase, and myoadenylate deaminase and were also periodic acid Schiff positive and stained basophilic with hematoxylin. Moreover, they reacted immunocytochemically with an antibody specific to fragment 17 to 24 of the published sequence of Alzheimer's cerebrovascular amyloid peptide. Immunoreactivity was lost when the antibody was adsorbed with the appropriate synthetic peptide. Ultrastructurally, the inclusions consisted of tubular arrays and were similar to those observed in human muscle in several pathological conditions. In type 1 myofibers of both tibialis anterior and soleus muscle, however, mitochondrial abnormalities including an increase in their number and size were detected, but tubular aggregates were not seen. These large mitochondria possessed an electron-dense inner chamber with an increased number of tightly packed cristae. The results obtained suggest that in these mice there is a disturbed lipid metabolism in skeletal muscle fibers that manifests itself with an accumulation of phospholipid in the form of sarcoplasmic reticulum tubules in the type 2 fibers and enlarged mitochondria with tightly packed cristae in the type 1 fibers. In addition, beta-amyloid protein was closely associated with the accumulated tubules and vesicles of sarcoplasmic reticulum and may represent dysregulation of amyloid precursor protein metabolism. Images Figure 1 Figure 2 Figure 3 PMID:9033257

  1. Apolipoprotein E4 allele as a predictor of cholinergic deficits and treatment outcome in Alzheimer disease.

    PubMed Central

    Poirier, J; Delisle, M C; Quirion, R; Aubert, I; Farlow, M; Lahiri, D; Hui, S; Bertrand, P; Nalbantoglu, J; Gilfix, B M

    1995-01-01

    Apolipoprotein E (apoE) is critical in the modulation of cholesterol and phospholipid transport between cells of different types. Human apoE is a polymorphic protein with three common alleles, APO epsilon 2, APO epsilon 3, and APO epsilon 4. ApoE4 is associated with sporadic and late-onset familial Alzheimer disease (AD). Gene dose was shown to have an effect on risk of developing AD, age of onset, accumulation of senile plaques in the brain, and reduction of choline acetyltransferase (ChAT) activity in the hippocampus of AD subjects. To characterize the possible impact of the apoE4 allele on cholinergic markers in AD, we examined the effect of apoE4 allele copy number on pre- and postsynaptic markers of cholinergic activity. ApoE4 allele copy number showed an inverse relationship with residual brain ChAT activity and nicotinic receptor binding sites in both the hippocampal formation and the temporal cortex of AD subjects. AD cases lacking the apoE4 allele showed ChAT activities close or within age-matched normal control values. The effect of the apoE4 allele on cholinomimetic drug responsiveness was assessed next in a group (n = 40) of AD patients who completed a double-blind, 30-week clinical trial of the cholinesterase inhibitor tacrine. Results showed that > 80% of apoE4-negative AD patients showed marked improvement after 30 weeks as measured by the AD assessment scale (ADAS), whereas 60% of apoE4 carriers had ADAS scores that were worse compared to baseline. These results strongly support the concept that apoE4 plays a crucial role in the cholinergic dysfunction associated with AD and may be a prognostic indicator of poor response to therapy with acetylcholinesterase inhibitors in AD patients. Images Fig. 2 PMID:8618881

  2. Induction of fibroblast apolipoprotein E expression during apoptosis, starvation-induced growth arrest and mitosis.

    PubMed Central

    Quinn, Carmel M; Kågedal, Katarina; Terman, Alexei; Stroikin, Uri; Brunk, Ulf T; Jessup, Wendy; Garner, Brett

    2004-01-01

    Apolipoprotein E (apoE) mediates the hepatic clearance of plasma lipoproteins, facilitates cholesterol efflux from macrophages and aids neuronal lipid transport. ApoE is expressed at high levels in hepatocytes, macrophages and astrocytes. In the present study, we identify nuclear and cytosolic pools of apoE in human fibroblasts. Fibroblast apoE mRNA and protein levels were up-regulated during staurosporine-induced apoptosis and this was correlated with increased caspase-3 activity and apoptotic morphological alterations. Because the transcription of apoE and specific pro-apoptotic genes is regulated by the nuclear receptor LXR (liver X receptor) alpha, we analysed LXRalpha mRNA expression by quantitative real-time PCR and found it to be increased before apoE mRNA induction. The expression of ABCA1 (ATP-binding cassette transporter A1) mRNA, which is also regulated by LXRalpha, was increased in parallel with apoE mRNA, indicating that LXRalpha probably promotes apoE and ABCA1 transcription during apoptosis. Fibroblast apoE levels were increased under conditions of serum-starvation-induced growth arrest and hyperoxia-induced senescence. In both cases, an increased nuclear apoE level was observed, particularly in cells that accumulated lipofuscin. Nuclear apoE was translocated to the cytosol when mitotic nuclear disassembly occurred and this was associated with an increase in total cellular apoE levels. ApoE amino acid sequence analysis indicated several potential sites for phosphorylation. In vivo studies, using 32P-labelling and immunoprecipitation, revealed that fibroblast apoE can be phosphorylated. These studies reveal novel associations and potential roles for apoE in fundamental cellular processes. PMID:14656220

  3. Apolipoprotein D Transgenic Mice Develop Hepatic Steatosis through Activation of PPARγ and Fatty Acid Uptake

    PubMed Central

    Labrie, Marilyne; Lalonde, Simon; Najyb, Ouafa; Thiery, Maxime; Daneault, Caroline; Des Rosiers, Chrisitne; Rassart, Eric; Mounier, Catherine

    2015-01-01

    Transgenic mice (Tg) overexpressing human apolipoprotein D (H-apoD) in the brain are resistant to neurodegeneration. Despite the use of a neuron-specific promoter to generate the Tg mice, they expressed significant levels of H-apoD in both plasma and liver and they slowly develop hepatic steatosis and insulin resistance. We show here that hepatic PPARγ expression in Tg mice is increased by 2-fold compared to wild type (WT) mice. Consequently, PPARγ target genes Plin2 and Cide A/C are overexpressed, leading to increased lipid droplets formation. Expression of the fatty acid transporter CD36, another PPARgamma target, is also increased in Tg mice associated with elevated fatty acid uptake as measured in primary hepatocytes. Elevated expression of AMPK in the liver of Tg leads to phosphorylation of acetyl CoA carboxylase, indicating a decreased activity of the enzyme. Fatty acid synthase expression is also induced but the hepatic lipogenesis measured in vivo is not significantly different between WT and Tg mice. In addition, expression of carnitine palmitoyl transferase 1, the rate-limiting enzyme of beta-oxidation, is slightly upregulated. Finally, we show that overexpressing H-apoD in HepG2 cells in presence o