Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020473 (hyperlipidemia)
 15,891 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Following ingestion of a fatty meal there is an increase in concentration of phospholipids and proteins in the plasma high density lipoproteins (HDL). To evaluate the resulting changes in HDL subclasses, the plasma HDL of six subjects were analyzed 4 to 8 h after ingestion of 100 ml of corn oil or 80 ml of corn oil with four eggs. Isopycnic density gradient ultracentrifugation of fasting plasma showed two broad components of HDL: a major peak of density (d) 1.11 to 1.17 g/ml (HDL3) and a smaller peak of d 1.07 to 1.11 g/ml (HDL2). Following ingestion of either type of fatty meal, there was an increase in lipoprotein mass in both peaks of HDL and their centers of mass were shifted to lower density (1.140 leads to 1.120 to 1.130 g/ml; 1.095 leads to 1.090 g/ml). Calculation of changes in HDL concentration (lipemic minus fasting) showed that the alterations in density gradient profile were due to a major increase in lipoproteins of d 1.102 to 1.137 g/ml, a smaller increase in a separate lipoprotein peak of 1.080 to 1.102 g/ml, and a small decrease in lipoproteins of d 1.137 to 1.165 g/ml. Redistribution of HDL mass into larger, less dense lipoproteins was also demonstrated by agarose gel chromatography or by minimal spin density gradient ultracentrifugation in a vertical rotor. The increase in mass of 1.080 to 1.102 lipoproteins was largely due to increased concentrations of phospholipid, cholesterol ester, and apoA-I, while the increase in 1.102 to 1.137 lipoproteins was due to increased concentrations of apoA-I, apoA-II, phospholipids, cholesterol, and cholesterol esters. Analytical ultracentrifugation of representative samples within these density intervals showed lipoprotein species with molecular weights and sedimentation coefficients, respectively, of 378,000, 5.8 (d 1.080 to 1.095); 248,000, 3.5 (d 1.110 to 1.120); and 173,000, 1.6 (d 1.135 to 1.150). Polyacrylamide gradient gel electrophoresis showed that the 1.080 to 1.102 lipoproteins contained a single lipoprotein band of diameter approximately 10.7 nm; the 1.102 to 1.137 lipoproteins contained a single band which varied in size fro 10.0 to 9.2 nm: and the 1.137 to 1.165 lipoproteins contained three species of diameters approximately 9.2, 8.8, and 8.2 nm. Within density intervals, the molecular weights, sedimentation coefficients, and diameters of the different lipoproteins were similar in fasting and lipemic plasma. Calculation of average molecular compositions shows that the major incremental HDL of d approximately 1.12 g/ml could be derived by addition of lipids to the largest species of fasting HDL3. Within density intervals, the particle contents of apoA-I and apoA-II were unchanged during lipemia, suggesting that apoprotein transfer causes interconversion of existing HDL species or formation of new particles with the same content of apoA-I and apoA-II as existing species.
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PMID:Changes in the distribution and composition of plasma high density lipoproteins after ingestion of fat. 679 85

Apolipoprotein (apo) E7 was originally identified by Yamamura et al. in subjects with atherosclerotic cardiovascular diseases (J. Clin. Invest. 1984;74:1229). However, the lipoprotein abnormalities associated with apo E7 phenotype have not been elucidated. In the current study, to clarify the physiological roles of apo E7, lipoprotein abnormalities were studied in 12 apo E7 heterozygotes. A total of seven subjects were hyperlipidemic and five subjects were normolipidemic. The apo E phenotype was apo E7/3 in 11 subjects and apo E7/4 in one subject. Polymerase chain reaction revealed that all of the subjects with apo E7 phenotype had the same mutation as that of apo E(Suita) as reported previously (J. Biochem. 1989;105:249). All the hyperlipidemic subjects were over 40 years of age and two of them also had and severe coronary heart disease. Ultracentrifugal analysis revealed that the cholesterol level both in very low density lipoprotein and in intermediate density lipoprotein (IDL) was substantially higher in hyperlipidemic apo E7 heterozygotes, compared with control subjects and that the IDL cholesterol was also increased even in normolipidemic apo E7 heterozygotes. Polyacrylamide gel electrophoresis of lipoproteins showed a midband, which implies the increase of remnant lipoproteins, in 11 subjects out of 12, irrespective of the presence or absence of hyperlipoproteinemia. In two cases, a broad beta pattern was observed similar to that seen in type III hyperlipoproteinemia. Dietary therapy was dramatically effective for the treatment of hyperlipidemia in patients with apo E7. These findings confirm that apo E is crucial for remnant lipoprotein metabolism and that apo E7 is related to the increase in serum remnant lipoproteins, which leads to hyperlipoproteinemia in association with obesity, aging and impaired glucose metabolism.
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PMID:Increased serum remnant lipoproteins in patients with apolipoprotein E7 (apo E Suita). 918 Feb 44