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)

Familial combined hyperlipidemia (FCHL) appears to be the most common, simply inherited hyperlipidemia strongly associated with coronary heart disease. In the family examined in this study, two of the siblings who met diagnostic criteria for FCHL had extensive clinical atherosclerosis before age 30, unusually premature for this form of hyperlipidemia. Lipoproteins and low-density lipoprotein (LDL) apolipoprotein (apo) B metabolism were characterized in these siblings in an attempt to gain insight into the cause of the rapid atherosclerosis in the two siblings so affected. LDL apo B production rates were very high in all three siblings (25 to 30 mg/kg/d), consistent with FCHL. beta-Very-low-density lipoprotein-beta (beta-VLDL) was present in the plasma of both siblings with accelerated atherosclerosis. The isoapolipoprotein E pattern in both of these siblings was E-3/E-2. In the third sibling, who was free of premature clinical atherosclerosis and lacked plasma beta-VLDL, the pattern was E-3/E-3. Thus, the heterozygote apo E-3/E-2 pattern may be related to the accumulation of beta-VLDL in persons with a very high apo B production rate. The abnormal accumulation of beta-VLDL may be one of the possible explanations for the rapid, premature atherosclerosis in the two siblings with FCHL in this kindred. Both male members in this kindred also had low levels of high-density lipoproteins, and thus may have had an additional risk of developing atherosclerosis due to this lipoprotein abnormality as well.
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PMID:Metabolism of apolipoprotein B in members of a family with accelerated atherosclerosis: influence of apolipoprotein E-3/E-2 pattern. 154 61

Bile acid kinetics and biliary lipid composition were determined in seven subjects with primary dysbetalipoproteinaemia. They were all homozygous for the apolipoprotein E isoform E-2 and six of them were hyperlipidaemic (type III hyperlipoproteinaemia). With or without hyperlipidaemia, the apo E-2/2 phenotype was associated with increased bile acid formation (mean increase compared with 32 normolipidaemic controls, 43%; P less than 0.025). The biliary lipid composition was not different from that seen in the controls. The results indicate that the uptake by the liver of apo E-containing remnant particles is of importance for the regulation of hepatic cholesterol metabolism in man. It is suggested that hepatic cholesterol synthesis is stimulated in dysbetalipoproteinaemia, and that this leads to a compensatory increase in bile acid synthesis.
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PMID:Bile acid metabolism in familial dysbetalipoproteinaemia: studies in subjects with the apolipoprotein E-2/2 phenotype. 211 78

The primary structure of apolipoprotein E (apo E) was investigated in seven type III hyperlipoproteinemic patients with the apo E-2/2 phenotype. Six of the patients had identical two-dimensional tryptic peptide maps. These differed from the normal apo E3 map by the altered mobility of a single peptide. Amino acid analysis and sequencing showed that apo E2 in these patients had a substitution of 158 Arg----Cys. The presence of this mutation in six of the seven type III patients confirms that this is the most common form of apo E2. The seventh type III patient had a unique map with a new peptide resulting from a substitution of 136 Arg----Ser. He was heterozygous for this and for the more common apo E2 (158 Arg----Cys) variant. His very low-density lipoprotein contained approximately five times more apo E2 (136 Arg----Ser) than apo E2 (158 Arg----Cys), as determined by cysteamine treatment and peptide mapping. This new apo E2 mutant thus appears to contribute significantly to the patient's hyperlipidemia.
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PMID:Apolipoprotein E2-Christchurch (136 Arg----Ser). New variant of human apolipoprotein E in a patient with type III hyperlipoproteinemia. 303 59

Eighty-six relatives of nineteen probands with type III hyperlipoproteinaemia were studied to determine the occurrence of hyperlipidaemia and to investigate the relation between apo E phenotypes, the occurrence of hyperlipidaemia, and the composition of the very low density lipoprotein (VLDL) fraction. Thirty-nine relatives were hyperlipidaemic: four type IIa or IIb, nine type III and twenty-six type IV. The predisposition for hyperlipidaemia was independent of the apo E phenotype. Hyperlipidaemic relatives with apo E phenotype E2/2 had a significantly (P less than 0.01) higher VLDL-cholesterol/VLDL-triglycerides ratio (1.26 +/- 0.35, n = 9) than those heterozygous for apo E allele epsilon 2 (0.66 +/- 0.12, n = 23) or without apo E allele epsilon 2 (0.69 +/- 0.11, n = 7). Normolipidaemic homozygous apo E-2 relatives had also a significantly (P less than 0.05) higher ratio (0.97 +/- 0.19, n = 6) than those heterozygous for (0.77 +/- 0.19, n = 31) or without the apo E allele epsilon 2 (0.74 +/- 0.13, n = 10). Thus, both hyper- and normolipidaemic apo E2 homozygotes have higher concentrations of VLDL remnants than the subjects heterozygous or without allele epsilon 2.
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PMID:Serum lipids, lipoproteins and apolipoprotein E phenotypes in relatives of patients with type III hyperlipoproteinaemia. 643 51

We analyzed the heterogeneity of apo E in very low density lipoprotein from 58 hyperlipidemic subjects with or without atherosclerosis, 69 patients with ischemic heart disease, and 100 apparently healthy individuals. Apo E gene frequencies in the group of healthy individuals were comparable with those in German and American populations. The distribution of six common apo E phenotypes in the groups of hyperlipidemia and ischemic heart disease was similar to that in the healthy group. In addition to the three major isoforms of apolipoprotein E (apo E-4, E-3, and E-2) and the new one (apo E-5) which was recently found in this laboratory, we have discovered an additional series of components, which showed themselves as at least three bands on an isoelectric focusing gel in the region of E-VII through E-V, in four patients with hyperlipidemia and atherosclerosis. The new series of apo E components, named apo E-Suita, was identical with the ordinary apo E in its interaction with heparin-Sepharose gel and with anti-apo E antibody. The most basic component of apo E-Suita (E-VII) was the unsialylated form and other components (E-VI and E-V), the sialylated forms. Family studies revealed that apo E-Suita was determined by inheritance of a new apo E allele located at the same locus as the hitherto known apo E components. Apo E-5 and apo E-Suita isoproteins had isoelectric points more basic than apo E-3, the parent type, by two and four units of charge, respectively. While the apo E-Suita isoprotein had the same molecular weight as ordinary major apo E isoproteins, the molecular weight of the apo E-5 isoprotein was approximately 1,500-2,000 lower than the other apo E isoproteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The incidence of abnormal apo E components, including apo E-5 and apo E-Suita, was high among patients with hyperlipidemia and ischemic heart disease (7:127), while we could not find such components among 100 healthy individuals. Moreover, five of seven patients with the abnormal apo E had overt atherosclerotic disease. The findings suggest that these kinds of apolipoprotein mutation are closely related to the development of atherosclerosis.
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PMID:New mutants of apolipoprotein E associated with atherosclerotic diseases but not to type III hyperlipoproteinemia. 648 Aug 26

Apolipoprotein E phenotypes were determined in 361 patients with hyperlipidemia and in controls. The E2 isoform was significantly more frequent in the group of hyperlipidemics (P less than 0.0005). This was not due to a higher frequency of E-2/2 homozygotes with type III hyperlipoproteinemia, but rather to a significantly higher frequency of E2 heterozygotes (P less than 0.0005). Subgrouping of hyperlipidemics into patients with a) hypertriglyceridemia, b) hypercholesterolemia and c) mixed hyperlipidemia revealed i) that isoform E2 was significantly more frequent in patients with hypertriglyceridemia (0.001 greater than P greater than 0.005), ii) that isoform E4 was significantly more frequent in patients with hypercholesterolemia (0.01 greater than P greater than 0.005) and iii) that isoforms E2 (P less than 0.005) and E4 (0.05 greater than P greater than 0.025) were both more frequent in patients with mixed hyperlipidemia. Roughly 20% of patients with mixed hyperlipidemia had one of the rare phenotypes E-4/4, -4/2 or -2/2. We conclude that alleles epsilon 2 and epsilon 4 both contribute to the susceptibility for, and/or phenotypic expression of hyperlipidemia. Whereas the gene epsilon 2 seems to exert its influence on plasma lipoproteins by an abnormal gene product (E2) that has reduced binding activity to lipoprotein receptors, the mechanism underlying the association of the epsilon 4 gene with hyperlipidemia is presently unclear.
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PMID:Apolipoprotein E phenotypes and hyperlipidemia. 669 47

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.
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PMID:A new isoform of apolipoprotein E--apo E-5--associated with hyperlipidemia and atherosclerosis. 671 69

Three probands heterozygous for a mutant of apolipoprotein AI (apo AIMarburg, Utermann et al. 1982a) were detected by screening of 2282 unrelated individuals resulting an a frequency estimate of about 1/750 in the German population. All three probands with apo AIMarburg had hypertriglyceridemia (triglyceride above 250 mg/dl) and subnormal HDL-cholesterol (below 30 mg/dl), but no other lipoprotein abnormalities. The kindreds of two probands with AIMarburg were studied. The family data are consistent with an autosomal codominant inheritance of the trait. A total of 16 heterozygous blood relatives with the mutant AIMarburg were detected in these kindreds. Analysis of the plasma lipid and lipoprotein levels in relation to the apo AI phenotype was complicated by the high prevalence of diabetes mellitus and thyroid disease in one kindred and of hyperlipidemia in both kindreds. No consistent relationship between plasma lipid and lipoprotein levels, and the mutant apo AI could be demonstrated. Instead the mutant apo AI and the dyslipoproteinemia seem to co-exist independently in these kindreds. Three sibs with the homozygous apo E-2/2 phenotype were detected in one kindred, and all three sibs had subnormal LDL-cholesterol and beta-VLDL, e.g., the lipoprotein abnormality characterizing primary dysbetalipoproteinemia. Genetic apo E phenotypes and the apo AI mutant segregated independently, indicating that the structural gene loci for apo E and apo AI are not closely linked.
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PMID:Apolipoprotein AIMarburg: studies on two kindreds with a mutant of human apolipoprotein AI. 681 31

The authors report their experience regarding the identification of Apo-E alleles on atheroma carotid plaques in 20 patients of both sexes diagnosed as suffering from severe carotid stenosis using Doppler tests. A DNA hybridization and amplification method was used to identify Apo E-2, Apo E-3 and Apo E-4 alleles and their various phenotypical combinations. The following results were obtained in the 20 plaques examined: Apo E-3/E-4 in 114 patients (70%), 2 diabetic patients Apo E-4/E-3, one vascular demented patient Apo E-2/E-3, and 3 plaques defined as severely calcified Apo E-2/E-2. It can therefore be seen that the majority of plaques (70%), considered a risk for future stroke due to altered carotid Doppler tests, does not differ greatly by the homozygote allele Apo E-3/E-3 commonly found in the blood of the so-called "normal" population. It is difficult to draw any conclusions from the alleles found in the other 5 patients due to their scarce statistical value and the limited number of carotid plaques examined, but there appears to be some sort of correlation between calcified plaque, hyperlipidemia and the allele Apo E-2/E-2, with an interchange of position between cysteine arginine amino acids in the Apo E sequences.
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PMID:[Atheroma plaque and Apo E alleles]. 876 17