Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

ApoB-100 and apoB-48 may be readily resolved in 3.3% sodium dodecyl sulphate-polyacrylamide gels. This study has characterized the relative chromogenicities (staining intensity/micrograms protein) of human apoB-100 and apoB-48 in various lipoprotein classes with Coomassie Brilliant Blue (R250) upon SDS-PAGE. The relation between dye uptake and the mass of each apoB species in any lipoprotein preparation, was linear at least within the concentration range of total apoprotein B which is optimally resolved in these gels (20-50 micrograms total apoprotein B), and was a function of the density of the particular lipoprotein fraction under investigation. There was a constant and characteristic difference between the chromogenicity for apoB-100 and that for apoB-48 as determined from the slopes of their respective chromogenicity curves. The slope of the lines describing staining intensity vs. protein mass for both apoB-100 and apoB-48 decreased as the density of the lipoprotein fraction increased. The slope of the line for apoB-100 was steeper than that for apoB-48 (i.e. chromogenicity apoB-100 greater than apoB-48) in all lipoprotein fractions where both were present. The relationship between the slopes of the lines for apoB-100 and apoB-48 was constant regardless of the density of the lipoprotein fraction. The chromogenicity curves for apoB-100 and for apoB-48 obtained when lipoprotein samples were applied to gels in concentrations conventionally used for this technique (i.e. 20-100 micrograms total apoB/gel) did not extrapolate to the same point on the ordinate, which precludes the use of a simple ratio or "chromogenicity factor" to describe their relative chromogenicities over this concentration range, Hence, a novel approach was developed to determine the relative mass of apoB-100/apoB-48 in lipoprotein samples, based on their staining characteristics in SDS-PAGE.
Atherosclerosis 1987 May
PMID:The chromogenicity and quantitation of apoB-100 and apoB-48 of human plasma lipoproteins on analytical SDS gel electrophoresis. 360 34

The effects of pantethine on LDL peroxidation in vitro are reported. LDL isolation by density gradient ultracentrifugation from 12 normal subjects were dialyzed 48 h under conditions allowing oxidation. The LDL peroxides were assayed for the presence of malondialdehyde (MDA) on the lipoprotein. The effect of peroxidation on the LDL protein moiety (apo B) was studied by SDS-gel electrophoresis. The presence in the dialysis buffer of 1 mM reduced glutathione or of an equimolar concentration of pantethine markedly inhibited the MDA formation in LDL. Less effective were 0.5 and 2 mM pantethine, while 10 mM pantethine did not prevent the LDL peroxidation. Both glutathione and pantethine (1 or 2 mM) preserved the original LDL electrophoretic mobility. The electronegative charge of LDL was correlated to the MDA production during the dialysis procedures. Freshly prepared LDL showed a single apo B band by SDS-gel electrophoresis (apo B-100). Following peroxidation 2 or 3 bands with higher molecular weight appeared. Both glutathione and pantethine (1 or 2 mM) strongly inhibited the appearance of higher molecular weight peptides. In appropriate concentrations therefore pantethine inhibits the LDL peroxidation in vitro, thus preserving the molecular integrity of apo B.
Atherosclerosis 1985 Oct
PMID:Effects of pantethine on in-vitro peroxidation of low density lipoproteins. 407 66

The distribution and the relative content of the isoprotein forms (isoforms) of apoprotein A-I (apo A-I) of HDL isolated from rat, rabbit and human plasma were studied by combined isoelectrofocusing and SDS-polyacrylamide gel electrophoresis. Rat apo A-I consists of seven isoforms having the same molecular weight (27,000) and moving in the 6.44-5.58 pH range. Isoforms 4, 5 and 6 are the major ones. Both rat HDL2 (1.090-1.210 g/ml) and purified rat apo A-I contain additional minor bands (designated 4a, 5a and 6a) which have the same isoelectric point as isoforms 4-6 but higher molecular weight (27,900). It is suggested that they might represent precursors of the main apo A-I isoforms. Rabbit apo A-I contains five isoforms focusing in the 5.69-5.34 pH range. Isoform 4 accounts for about 90% of apo A-I mass. Human apo A-I consists of five isoforms focusing in the pH range 5.91-5.0. Isoforms 3 and 4 are the main ones: their respective contents show high degrees of individual variation.
Atherosclerosis 1984 Feb
PMID:Separation of the isoprotein forms of apoprotein A-I of rat, rabbit and human HDL by combined isoelectrofocusing and SDS-polyacrylamide gel electrophoresis. 642 88

Aortic intima-medias of normal and cholesterol-fed rabbits were studied with EM and cells were isolated by enzyme digestion. The composition of cytoskeletal and cytocontractile proteins was determined with SDS-PAGE and the primary growth and thymidine incorporation rates were assessed after seeding the cells into tissue culture flasks. Ultrastructurally, the SMCs in the thickened atherosclerotic intima differed from the contractile medial SMCs in containing lipid vacuoles, enlarged endoplasmic reticulum and a reduced number of myofilaments, thus showing characteristics of dedifferentiated SMCs. In SDS-PAGE, freshly isolated cells from the atherosclerotic intima-medias had a lower content of myosin and actin, and a higher proportion of vimentin and desmin than SMCs from normal aortas. Enzyme-isolated SMCs from normal aortas did not start to grow and incorporate radioactive thymidine until 5-6 days after seeding, whereas those from atherosclerotic aortas did so within 2 days. After a week in culture, SMCs from both sources resembled each other, and had decreased contents of myosin and actin, and increased concentrations of vimentin in comparison to freshly isolated normal SMCs. The present results indicate (a) that morphological dedifferentiation of SMCs in aortic lesions of cholesterol-fed rabbits is associated with an increased proportion of the proteins of the intermediate filaments and a decrease in those of the thin and thick myofilaments as determined with SDS-PAGE, and (b) that similar changes take place when normal SMCs are cultured in vitro. The results also suggest (c) that enzyme-isolated atherosclerotic SMCs proliferate in a primary culture without the lag period that normal SMCs apparently require for dedifferentiation.
Atherosclerosis 1984 Jul
PMID:Growth properties and composition of cytoskeletal and cytocontractile proteins in aortic cells isolated and cultured from normal and atherosclerotic rabbits. 646 13

An application of SDS gradient polyacrylamide slab gel electrophoresis to the analysis of lipoprotein polypeptides is described. The 10-15% polyacrylamide gradient provides a high degree of resolution and sensitivity resulting in a single separation of the major apoproteins which can be easily visualized. When combined with autofluorography, individual protein mass and radioactivity can be determined densitometrically while still retaining excellent resolution. Examples of rat lymph and plasma apolipoproteins are shown, and apparent heterogeneity of certain apoprotein subgroups is described.
Atherosclerosis 1984 Nov
PMID:Application of SDS gradient polyacrylamide slab gel electrophoresis to analysis of apolipoprotein mass and radioactivity of rat lipoproteins. 651 72

Collagenous components were extracted from bovine aorta by pepsin digestion. Differential salt precipitations separated the interstitial from the basement membrane (BM) collagens, and the latter were subsequently separated into three distinct types. Ion exchange chromatography, SDS-slab gel electrophoresis, cyanogen bromide and protease V8 peptide mapping, and amino acid analysis were used to characterize the component chains within each of these types. The major BM-class contained three distinct chains which were identical to the alpha 1(V), alpha 2(V) and alpha 3(V) chains of type V collagen from normal human placenta. The stoichiometry of the chains suggests a [alpha 1(V)]2 alpha 2(V)-helical organization, but the role of the alpha 3(V) chain in the overall structural organization of collagen V remains unknown. The second BM-class contained a heterogeneous group of molecules ranging in size from 40 000 to 140 000 daltons. Two predominant chains within this group were characterized as the alpha 1(IV) and alpha 2(IV) chains of type IV collagen. The last class of BM collagens consisted primarily of high molecular weight components; upon reduction these gave rise to two low molecular weight collagenous species (40 K and 45 K) characteristic of type VI, low molecular weight or 'linker' collagens. The functional roles of the isolated BM collagens, either individually or collectively, has not been ascertained to date.
Atherosclerosis 1984 Jan
PMID:Characterization of basement membrane collagens of bovine aortae. 669 80

Heterogeneity of apolipoprotein E (apo E) was analyzed by isoelectric focusing of apo VLDL in patients with hyperlipidemia and/or atherosclerosis. Six major apo E phenotypes were shown, in agreement with the current genetic model which is composed of 3 major apo E isoproteins, apo E-4, apo E-3 and apo E-2, resulting from three apo E alleles, epsilon 4, epsilon 3 and epsilon 2, at a single genetic locus. We recognized an additional apolipoprotein band, which is located basic to apo E-4 on an isoelectric focusing gel, in 3 patients with hyperlipidemia. The new apolipoprotein component, named apo E-5, was identical with ordinary apo E in apparent molecular weight by SDS-polyacrylamide gel electrophoresis and in its interactions with heparin-Sepharose gel and with anti-apo E antibody. This mutant apo E isoprotein had an isoelectric point more basic by one unit of charge than apo E-4. Two of 3 patients had the phenotype E5/3, and the other the phenotype E5/4. Genetic analysis of the apo E phenotypes in family members of the patients indicated the presence of a new apo E allele (epsilon 5) at the same genetic locus as hitherto known alleles. Since most of the subjects above 50 years old with apo E-5 had ischemic heart disease or cerebral infarction, it was suggested that the mutant apo E-5 may possibly be related to the development of atherosclerosis.
Atherosclerosis 1984 Feb
PMID:A new isoform of apolipoprotein E--apo E-5--associated with hyperlipidemia and atherosclerosis. 671 69

Apolipoprotein A-I was quantitated by electroimmunoassay in buffer-soluble fractions of both grossly normal intima and raised atherosclerosis lesions of the human aorta. The mean value for apolipoprotein A-I content in microgram/mg tissue dry weight of normal intima (12 cases) was 0.71 +/- 0.10 S.E. and of aortic plaques (19 cases) was 0.64 +/- 0.40 S.E. When compared to the buffer-extractable apolipoprotein B content measured in these same cases from both regions, the ratio of apolipoprotein B to apolipoprotein A-I was approximately 6. No apolipoprotein A-I was measurable in tunica media. Following differential ultracentrifugation into d less than 1.063, d 1.063-1.21 and d greater than 1.21 fractions, the distributions of recovered apolipoprotein A-I were, respectively: 1, 94 and 5% for normal intima, 19, 31 and 50% for plaques and 1, 89 and 10% for plasma. Characterization of a chromatographically purified d 1.063-1.21 or HDL density fraction from fatty-fibrous plaques demonstrated particles of between 60 and 120 A diameter, a characteristic apolipoprotein A-I band by SDS-polyacrylamide gel electrophoresis, and a precipitin peak closely migrating with that for plasma HDL by two-dimensional immunoelectrophoresis. The d greater than 1.21 density fraction from plaques isolated by affinity chromatography on a Sepharose-anti-apolipoprotein A-I column contained small amounts of phospholipid but no measurable cholesterol. The d 1.063-1.21 density fraction from plaques showed a significant increase in percent free cholesterol and phospholipid contents and decrease in cholesteryl ester content relative to plasma HDL. This increase in free cholesterol could represent evidence for an anti-atherogenic mechanism wherein infiltrated HDL removes cholesterol together with phospholipid from the arterial wall.
 ...
PMID:Lipoproteins containing apolipoprotein A-I extracted from human aortas. 680 57

Estimation of collagens types I and III in pepsin digests and by analysis of specific cyanogen-bromide derived peptides by SDS-polyacrylamide gel electrophoresis, has indicated that both the undiseased human aortic media and the atherosclerotic plaque of the diseased intima contain more type I collagen than type III. There was only a relatively small shift in composition in favour of type I collagen in the diseased compared to the undiseased tissue. Diffusely thickened intima was similar in composition to the atherosclerotic plaque. These results suggest that both atherogenesis and diffuse intimal thickening may involve primarily smooth muscle cell hyperplasia with increased overall collagen production but little alteration in cell phenotype as regards the relative proportions of the individual collagens produced. They do not support the contention that atherosclerosis involves a 'transformation' of smooth muscle cells to fibroblast in type, whereby a major switch in synthesis occurs from largely type III collagen to mainly type I in disease. Type V collagen(s) containing both alpha A- and alpha B-chains has been detected throughout the vessel wall in diffusely thickened intima, media and adventitia, as well as in the plaque where, in the latter case, a marked enrichment relative to interstitial collagens was noted. This is presumed to reflect the relatively cellular nature of the atherosclerotic lesion. The alpha C-chain of type V collagen was detected in porcine but not human aorta.
Atherosclerosis 1982 Mar
PMID:Collagen polymorphism in the normal and diseased blood vessel wall. Investigation of collagens types I, III and V. 708 17

This study investigated free hemin induced modifications in low density lipoprotein (LDL). By use of fluorescent probes hemin was found to associate with LDL thereby inducing peroxidation of both lipids and protein. Upon LDL peroxidation, covalent crosslinking of apolipoprotein B (Apo B) occurred as judged by SDS-PAGE. Concomitantly, a multifluorophore emission developed, which included contribution of bityrosines. The simultaneous formation of protein aggregates and bityrosines was interpreted as the involvement of intermolecular bityrosines in the hemin induced crosslinking of Apo B. Since LDL protein aggregation relates to conversion of macrophages into foam cells, hemin should be considered as an endogenous trigger of atherosclerosis.
 ...
PMID:Oxidative crosslinking of LDL protein induced by hemin: involvement of tyrosines. 769 84


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>