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

(1) Lipoproteins from the serum of male turkeys maintained on a normal diet were separated by sequential preparative ultracentrifugation into VLDL (d less than 1.006 g/ml), LDL (d = 1.006-1.063 g/ml), HDL (d = 1.063-1.21 g/ml) and VHDL (d greater than 1.21 g/ml). Lipoprotein density classes were characterized by analytical ultracentrifugation, agarose electrophoresis, immunodiffusion and immunoelectrophoresis, and by quantitative determination of protein, lipids and individual phosphatides. (2) HDL were the major density class representing 75% of the total lipoprotein content, LDL accounted for approximately 20% and VLDL for only 3-5% of the total lipoproteins. (3) VLDL were characterized by a relatively low content of glyceride (34%). Cholesterol esters were the major lipid (38%) of LDL, and the phospholipids (26%) of HDL. Glycerides of all major density classes consisted of equal amounts of triglycerides and diglycerides. (4) Phosphatidylcholine was the major phosphatide in all density classes. The composition of phosphatides was very similar in the VLDL and LDL, but it was different in the HDL. The ratio of phosphatidylcholine/sphingomyelin was higher in HDL than in VLDL and LD. (5) Immunological and electrophoretic studies showed that all three major density classes consisted of two lipoprotein families designated, in analogy to the human serum lipoprotein system [1], as LP-A and LP-B. The exception was HDL3 (d = 1.125-1.21 g/ml) which contained only LP-A. (6) ApoB was insoluble in aqueous buffers but could be solubilized after reduction and carboxymethylation. No C- or N-terminal amino acids were released by the usual chemical methods. The carbohydrate moiety of ApoB contained mannose, galactose and galactosamine. (7) ApoA consisted of a non-identical polypeptides designated in analogy to the human polypeptides as A-I and A-II. A-I was the major ApoA polypeptide and had a molecular weight of about 27,000. This polypeptide contained no half cystine, and the aspartic acid as the N-terminal and alanine as the C-terminal amino acids. A-II had a molecular weight of about 10,000, contained no half cystine and had alanine as the C-terminal amino acid. A-II showed no N-terminal amino acid by either dansylation, dinitrophenylation or Edman's procedure. Neither A-I nor A-II contained neutral sugars or hexosamines. (8) Concentrations of polypetides analogous to human ApoC, ApoD and "arginine-rich" polypeptide, if present, were too low for their unequivocal chemical characterization.
Atherosclerosis
PMID:Lipid transport in the avian species. Part I. Isolation and characterization of apolipoproteins and major lipoprotein density classes of male turkey serum. 18 83

A 1,500 Cal test meal was used to study in man the apoprotein B-carbohydrate content and composition of VLDL, IDL and LDL in relation to the variation of plasma lipids and lipoproteins and the VLDL-apoprotein composition. Three essential facts emerge from the study: (1) the mirror image (inverse significant correlation) between VLDL-apo B plasma concentration and N-acetylglucosamine content of apo B; (2) a reduction in total carbohydate concentration of VLDL- and LDL-apo B, 2--4 h after the test meal and a trend to a reduction in the mannose content; (3) a significant correlation between sialic acid and apoprotein B concentration in plasma LDL during fasting. The effect of diet and subsequent fasting on carbohydrates of lipoproteins and the consequence of such changes on lipoprotein uptake are briefly discussed.
Atherosclerosis 1978 Aug
PMID:Relationship between the carbohydrate content of apoproteins of VLDL, IDL, and LDL and the plasma level of these lipoproteins in man. Short dietary effect. 21 83

1. Carbohydrate composition of serum low and high density lipoproteins obtained from 5 nonhuman primate species (chimpanzee, patas, baboon, rhesus, and spider) and humans was studied. 2. Individual lipoproteins were isolated from pooled sera of each species by ultracentrifugal flotation between the densities 1.019-1.063 for LDL-2; 1.063-1.12 for HDL-2; and 1.12-1.21 for HDL-3. After delipidation, sialic acid, fucose, glucosamine, mannose, galactose, and glucose were determined on apo LDL-2, apo HDL-2, and apo HDL-3. 3. Glucosamine, galactose, and mannose constituted a major component of the sugars in apo LDL-2, with similar relative proportions in all species. Sialic acid, fucose, and glucose formed a minor component, the proportions of which varied greatly among the species. 4. Unlike apo LDL-2, sialic acid, fucose, and glucosamine constituted the bulk of the sugars in apo HDL-2 and apo HDL-3. Mannose, galactose, and glucose were minor components, with galactose predominating. 5. Qualitative differences were observed in electrophoretic mobilities of apo HDL-2 and apo HDL-3 on polyacrylamide gel. One faster moving band was unique to chimpanzee. 6. Intraspecies differences in the content of sialic acid and fucose of apolipoproteins may be related to lipoprotein metabolism and species susceptibility (or resistance) to either spontaneous or diet-induced atherosclerosis.
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PMID:Carbohydrate composition of serum low and high density lipoproteins of nonhuman primate species. 23 83

Rabbits become hypercholesterolemic when transferred from commercial feed to a low fat, cholesterol-free semisynthetic diet. The role of different dietary components in mediating this effect was investigated by varying the composition of the semisynthetic diet and of the commerical feed. Addition of alfalfa to the semisynthetic diet prevented the normal hypercholesterolemic response, but other plant products, including several with high fibre content, were ineffective. Increasing the content of powdered cellulose appeared to enhance the response. A commercially formulated diet in which the alfalfa and soybean meal components were replaced by ground corn and oats did not produce a significant elevation of plasma cholesterol. Substitution of different sugars or starches for the dextrose in the semisynthetic diet gave variable results, but of those tested, only potato starch prevented the hypercholesterolemia. The type of protein used in the semisynthetic diet had a marked influence on the level of plasma cholesterol. Semisynthetic diets containing proteins from animal sources gave higher plasma cholesterol levels than those containing proteins from plant sources. Very low levels were obtained with a low choline semisynthetic diet containing soy protein isolate, and supplementation with choline and methionine only raised the level to that normally obtained with commercial feed. Replacement of the salt mixture in the semisynthetic diet by one specially recommended for rabbits made no significant difference to the hypercholesterolemic response. Prevention of coprophagy did not significantly affect plasma cholesterol levels in rabbits on either commerical or semisynthetic diets. Growth performance was generally better on commercial feed than on semisynthetic diets but there was no direct correlation between weight gain and level of plasma cholesterol in rabbits on the different semisynthetic diets.
Atherosclerosis
PMID:Plasma cholesterol levels in rabbits fed low fat, low cholesterol diets: effects of dietary proteins, carbohydrates and fibre from different sources. 94 88

The monosaccharide content was examined in apoprotein B and lipids of total low density lipoprotein (LDL) preparations isolated from the blood of healthy individuals and patients with coronary atherosclerosis, as well as in desialylated and sialylated LDL obtained by affinity chromatography on Ricinus Communis Agglutinin-agarose. The glycoconjugates of total apoprotein-B of healthy subjects' LDL were found to consist of N-acetylglycosamine, galactose, mannose and sialic acid in a molar ratio of 2:1:2.5:1. The content of protein-bound neutral sugars was the same in healthy subjects and patients, while there was a lower sialic acid amount in the patients. The level of protein-bound sialic acid in patients' desialylated LDL was 2- to 3-fold lower than that in sialylated LDL. In contrast to apoprotein-B glycoconjugated, the lipid-bound carbohydrate chains of total LDL preparations had N-acetylgalactosamine and glucose, but not mannose. In total LDL from patients, the content of all lipid-bound carbohydrates was 1.5- to 4-fold lower than that in LDL from healthy subjects. In healthy subjects and in patients alike, the neutral sugar content of a lipid subfraction of desialylated LDL was lower than in those of sialylated LDL. It is concluded that atherogenic desialylated LDL differ from non-atherogenic sialylated LDL in neutral sugar levels.
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PMID:[Carbohydrate composition of native and desialylated low density lipoproteins in the plasma of patients with coronary atherosclerosis]. 128 15

Plasma lipid, lipoprotein and apolipoprotein levels are known to decrease after major surgery. Coronary artery bypass surgery additionally involves use of extracorporeal circulation by use of a cardiopulmonary bypass pump, which necessitates hemodilution due to saline dextrose infusion to prime the pump. To investigate changes in lipids, lipoproteins and apolipoproteins as well as changes in C-reactive protein and albumin we conducted a study on 22 patients undergoing cardiac surgery involving cardiopulmonary bypass. Timed arterial blood samples were taken before, during and after cardiopulmonary bypass. At the onset and during cardiopulmonary bypass a rapid and significant fall was observed in all lipids and lipoproteins except lipoprotein(a) with recovery to near basal levels by 72 h for cholesterol, triglycerides, high density lipoprotein cholesterol and albumin, while apolipoproteins AI and B remained below basal levels during the postoperative period up to 72 h. In contrast, lipoprotein(a) levels increased at the onset, doubled during cardiopulmonary bypass and remained elevated postoperatively. On the other hand, C-reactive protein levels fell at the onset and during cardiopulmonary bypass but they became markedly elevated postoperatively. When results were corrected for hemodilution, the response patterns remained unchanged. As lipoprotein(a) is both atherogenic and thrombogenic, its elevation during cardiopulmonary bypass may be clinically important.
Atherosclerosis 1992 Nov
PMID:Paradoxical response of plasma lipoprotein(a) in patients undergoing cardiopulmonary bypass. 814 47

We have previously demonstrated the heterogeneity of N-linked sugar chains of apolipoprotein (apo) B-100 in Watanabe heritable hyperlipidemic (WHHL) rabbit and fasting Japanese White rabbits (Arteriosclerosis, 10 (1990) 386-393). To investigate further the role of N-linked sugar chains of apo B-100 in lipid metabolism, we examined the correlation between the N-glycosylation of apo B-100 and serum cholesterol levels in WHHL rabbits. The N-linked sugar chains of apo B-100 were liberated by hydrazinolysis, followed by NaB3H4 reduction and were fractionated by paper electrophoresis and BioGel P-4 column chromatography. These were found to consist of one neutral (N) and two acidic fractions (A1 and A2). N contained a high mannose type oligosaccharide consisting of Man5.GlcNAc2 to Man9.GlcNAc2, while A1 and A2 contained monosialylated and disialylated complex type oligosaccharides, respectively. The molar ratio varied among the 5 WHHL rabbits. There was an inverse correlation between the ratio of acidic oligosaccharide fractions (A1 + A2) and serum cholesterol levels (r = -0.971, P less than 0.01) in the 5 WHHL rabbits. These results indicate that the N-glycosylation of apo B-100 is closely related to cholesterol metabolism in WHHL rabbits.
Atherosclerosis 1992 Apr
PMID:Association of N-glycosylation of apolipoprotein B-100 with plasma cholesterol levels in Watanabe heritable hyperlipidemic rabbits. 159 Aug 27

This study examined the effects of simvastatin, an inhibitor of HMG-CoA reductase, on the metabolism of labelled human low density lipoprotein (LDL) in animal models. Administration of 10 mg/kg per day simvastatin for 2 weeks reduced the levels of total cholesterol, LDL-cholesterol and triglycerides by 5.7 mg/dl (16%), 8.8 mg/dl (36%) and 4.9 mg/dl (13%), respectively in guinea pigs. High density lipoprotein-cholesterol levels rose 0.8 mg/dl (29%) by simvastatin treatment. Measurements of turnover of LDL were determined between simvastatin-treated guinea pigs and untreated guinea pigs using intravenous injection of 131I-labelled LDL and 125I-labelled galactose-treated LDL to quantify the LDL receptor pathway. Simvastatin significantly increased the fractional catabolic rate (FCR) of the LDL receptor-dependent pathway. In contrast, the FCR of the LDL receptor-independent pathway was not altered by simvastatin therapy. The FCR for LDL isolated from simvastatin-treated subjects compared to that from control subjects was very similar in both control and simvastatin-fed guinea pigs. These findings suggest that simvastatin mainly reduced serum cholesterol levels by accelerated FCR of LDL receptor mediated pathway.
Atherosclerosis 1991 Sep
PMID:Effect of simvastatin on receptor mediated metabolism of low density lipoprotein in guinea pigs. 166 74

Reduction of the blood levels of low density lipoprotein (LDL) is important for lowering the incidence of atherosclerosis. In this study, LDL was directed to rat parenchymal liver cells by lactosaminated Fab fragments of anti-apolipoprotein B antibodies (LacFab). We followed the fate of intravenously injected complexes of LacFab and [3H]cholesteryl oleate-labeled LDL. Complexing of LacFab to LDL led to rapid disappearance of LDL from the circulation. At 30 minutes after injection, the liver contained 58.5 +/- 9.0% of the injected dose (at that time the liver contained only 5.7 +/- 2.2% of an injected dose of free LDL). Liver uptake was blocked by N-acetylgalactosamine but not by N-acetylglucosamine, which indicates that galactose-specific recognition sites are responsible for the LacFab-induced hepatic uptake. By isolating liver cells, it was found that parenchymal, endothelial, and Kupffer cells account for 87%, 3%, and 10% of the total hepatic uptake, respectively. Subcellular fractionation of the liver indicated that the complexes are rapidly internalized and transported to lysosomes. Within 1 hour after injection, virtually all the [3H]cholesteryl oleate of the internalized LDL was hydrolyzed; hydrolysis was followed by excretion of radioactivity into the bile. Compared with rats injected with native [3H]cholesteryl oleate-labeled LDL, eight times as much radioactivity was excreted into the bile during the first 4 hours after the injection of LacFab-complexed [3H]cholesteryl oleate-labeled LDL. Thus, LacFab induces enhanced hepatic uptake of LDL via galactose receptors on the parenchymal cells, followed by processing in lysosomes and excretion into the bile. In this way, LacFab induces an increased irreversible removal of LDL cholesterol from the body.
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PMID:Enhanced hepatic uptake and processing of cholesterol esters from low density lipoprotein by specific lactosaminated Fab fragments. 193 82

Based on the results of previous investigations that pollen Typhae, a Traditional Chinese Medicine, Had antiatherogenic effects, several components were isolated successively from the drug and their effects on porcine aortic endothelial cell (EC) and smooth muscle cell (SMC) cultures as well as on platelet aggregation were examined. 12 components isolated from Pollen Typhae have been identified on their chemical structures and biological effects. 4 of them showed different evident antiatherogenic effects. 1) Isorhamnetin-3-O-rhamnosyl-glucoside could stimulate EC to produce tPA and PGI2; 2) Quercetin-3-O-neohesperidose could protect EC from injury by fibrin, as well as raise tPA activity; 3) beta-Sitosterol palmitate could inhibit SMC proliferation and 4) beta-Sitosterol glucoside showed an inhibitory effect on platelet aggregation. These results would provide some information for the search of new drugs in the treatment and prevention of atherosclerosis.
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PMID:The antiatherogenic effects of components isolated from pollen typhae. 211 85


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