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)

Spontaneously hyperlipidemic (SHL) mice are Japanese wild mice (KOR) with disruption of the apolipoprotein E (Apo E) gene. These mice (KOR-Apoe(shl)) are superhypercholesterolemic and develop severe xanthoma, but their atherosclerosis is relatively mild compared with Apo E knockout mice. First, we tested whether this distinction is due to additional mutation of the Apoc1 and/or Apoc2 genes in KOR-Apoe(shl). Southern blot analysis, but found no gross disruption of these genes. Next, we tested whether the phenotypic distinction is due to differences in the genetic background. To this end, we established three lines of congenic SHL mice with a genetic background of C57BL/6, BALB/c or C3H/He, and named them, respectively, C57BL/6.KOR-Apoe(shl) (B6.KOR-Apoe(shl)), BALB/c.KOR-Apoe(shl) (C.KOR-Apoe(shl)) and C3H/He.KOR-Apoe(shl) (C3.KOR-Apoe(shl)). Hypercholesterolemia was most severe in KOR-Apoe(shl) followed the by others as follows; KOR-Apoe(shl)>>C3.KOR-Apoe(shl)>C.KOR-Apoe(shl)>B6.KOR-Apoe(shl). In contrast, atherosclerosis was most severe in B6.KOR Apoe(shl) followed by the others: B6.KOR-Apoe(shl)>C.KOR-Apoe(shl)>>C3.KOR-Apoe(shl)> or =KOR-Apoe(shl). This order, however, did not match that in xanthoma, which was highly prominent in KOR-Apoe(shl) but mild in B6.KOR-Apoe(shl), C.KOR-Apoe(shl) and C3.KORApoe(shl). This order, however, did not match that in xanthoma, which was highly prominant in KOR-Apoe(shl) but mild in B6.KOR-Apoe(shl), C.KOR-Apoe(shl) and C3.KOR-Apoe(shl). These distinctions suggest that the severity of each of the phenotypes is determined by distinct genetic backgrounds which probably are composed of polymorphism of lipid metabolism-related proteins. We found that apolipoprotein A-I is decreased in each SHL strain and polymorphic between B6.KOR-Apoe(shl) and the other strains examined. This polymorphism may be related to the most severe atherosclerosis observed in B6.KOR-Apoe(shl). It is most likely that combination of such polymorphisms is due to the genetic background accountable for phenotype distinctions.
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PMID:Four strains of spontaneously hyperlipidemic (SHL) mice: phenotypic distinctions determined by genetic backgrounds. 1186 33

VasoCare therapy, which involves the administration of autologous blood following the ex vivo exposure to physico-chemical stressors, has been shown to modulate immune responses. Since immune mechanisms have been recognized to be pivotal in the pathogenesis of atherosclerosis, we hypothesized that VasoCare treatment would inhibit atherosclerosis in LDL-R (-/-) mice. Three groups of LDL-R (-/-) mice were studied: a control group that was fed normal chow (Group I) and no other treatment; a control group that received a high cholesterol (HC) diet for 8 weeks (group II) with sham saline injections; and a third group (III) that received HC diet for 8 weeks and VasoCare treatment initiated after four weeks of HC feeding. Atherosclerotic area (AA), relative to total aortic area (TA), was assessed after 8 weeks of HC feeding by oil red O staining, and cross sectional plaque area at the level of the aortic valve leaflets was determined by quantitative morphometry. HC mice exhibited substantial aortic lipid deposition which was profoundly reduced in the VasoCare treated animals (AA/TA ratios in group II: 0.32+/-0.15 vs. group III: 0.17+/-0.06; P<0.05). This was associated with a significant decrease in cross sectional area of plaque in the aortic sinuses. VasoCare therapy also reduced the xanthoma formation and limb swelling characteristic of this animal model. However, cholesterol levels, measured by an enzymatic assay, showed similar marked increases in total serum cholesterol (CHO) in the animals receiving HC diet alone and those receiving the HC diet and VasoCare treatment [group I: 5.4+/-0.8 mM, group II: 46.7+/-3.6 mM, and group III: 44.7+/-2.8 mM (P<0.01 vs. group I)]. We conclude that VasoCare treatment inhibits progression of atherosclerotic lesions in a murine model of human familial hypercholesterolemia by a mechanism independent of cholesterol lowering.
Atherosclerosis 2002 May
PMID:Effects of VasoCare therapy on the initiation and progression of atherosclerosis. 1194 96

We evaluated a 69-year-old Japanese woman with apolipoprotein (apo) A-I deficiency, high levels of low-density lipoprotein (LDL)-cholesterol, hypertension and impaired glucose tolerance. The patient had corneal opacity, but neither xanthomas, xanthelasma, nor tonsillar hypertrophy. She was not symptomatic for coronary heart disease (CHD), and had normal electrocardiograms at rest and exercise using a cycle ergometer. She had severely reduced levels of high-density lipoprotein (HDL)-cholesterol (0.10-0.18 mmol/l) and no apo A-I (<0.6 mg/dl). LDL-cholesterol and apo B as well as apo E were increased even under treatment with 10 mg pravastatin per day. Gel filtration chromatography revealed that in addition to VLDL and LDL fractions, she had apo A-II rich and apo E rich fractions, which were present in the HDL fraction separated by ultracentrifugation. A cytosine deletion was identified by genomic DNA sequencing of the apo A-I gene of the patient at the third base of codon 184 in the fourth exon, which led to a frame shift mutation and early termination at codon 200. This patient is the oldest among those with apo A-I deficiency reported in the literature, and she had no symptoms of CHD despite the accumulated risk for the disease.
Atherosclerosis 2002 Jun
PMID:Apolipoprotein A-I deficiency with accumulated risk for CHD but no symptoms of CHD. 1199 60

Mutations in the LDL receptor (LDLR) cause familial hypercholesterolaemia (FH) in an autosomal dominant manner. The condition frequently progresses to coronary atherosclerosis. We describe a patient with FH, but without ischaemic heart disease, who had a novel frameshift mutation (327insC) in exon 4 of the LDLR gene. This mutation introduced a premature termination codon (TGA, codon 158). The patient was a 59-year-old man who had presented with hypercholesterolaemia and a plasma total cholesterol (TC) concentration of 12.2 mmol/L at age 44 years. The mutation 327insC in this patient was heterozygous and hypercholesterolaemia was common within his family. Despite taking lipid-lowering medications (probucol and pravastatin) for more than 20 years, his TC concentration hardly fell below 7.8 mmol/L. However, neither the patient nor anyone else in his family developed characteristic symptoms of ischaemic heart disease or xanthoma. This patient was discovered by an intensive mutation survey among 22 unrelated Japanese with FH mainly in the Kanto area of Japan, suggesting a low incidence of the mutation in the area.
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PMID:Japanese familial hypercholesterolaemia with a 327insC mutation in the LDL receptor gene. 1222 64

L-arginine, a semi-essential amino acid, can enhance the synthesis of nitric oxide (NO) via the nitric oxide synthase pathway. Enhanced bioavailability of NO may prevent activation of pro-inflammatory endothelial genes by the inhibition of nuclear transcription factor NF 3B, thus preventing the expression of adhesion molecules on endothelial surfaces. Animal studies have demonstrated that the chronic administration of L-arginine reduces the extent of atherosclerosis and prevents xanthoma development in LDL receptor knockout mice. Human studies have demonstrated improvement in endothelium vasodilator function both in coronary arteries and forearm flow responses. In addition oral L-arginine reverses an increased monocyte-endothelial adhesion in men with coronary artery disease and normalizes platelet aggregation in hypercholesterolemic humans. L-arginine may be a promising drug in the therapy of atherosclerosis. (Int J Cardiovasc Interventions
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PMID:The effects of L-arginine on atherosclerosis and heart disease. 1262 95

A 4-year-old boy presented with multiple tuberous xanthomata and a fasting plasma sterol concentration of 18.3 mmol/L, consisting primarily of cholesterol. Two months after changing from an unrestricted diet to a cholesterol-lowering diet, the plasma sterol concentration decreased to 4 mmol/L. Fasting plasma cholesterol levels for his father and mother were 7.3 mmol/L and 6.0 mmol/L, respectively. The degree and rapidity of the child's response to dietary control, together with the fasting cholesterol results of both parents suggested a diagnosis of sitosterolaemia. Gas chromatography and mass spectrometry of the patient's plasma sterol levels showed that the percentage of beta-sitosterol was raised at 12.76%, as was campesterol (6.26%), and stigmasterol (0.71%), confirming the diagnosis of sitosterolaemia. The addition of cholestyramine 4 g/day to a low sterol diet maintained the plasma sterol concentration at 4 to 5 mmol/L, and gradual regression of the xanthoma was observed. These findings indicate that a diagnosis of sitosterolaemia, a treatable cause of premature atherosclerosis, should be considered in children with severe hypercholesterolaemia whose plasma cholesterol level is highly responsive to dietary manipulation.
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PMID:Sitosterolaemia and xanthomatosis in a child. 1277 58

Xanthomas are deposits of lipids in the skin and sometimes of the subcutaneous tissue that are expressed clinically as yellowish papules and plaques, nodules, and tumors. They are often, but not always, a consequence of hyperlipidemia. In these cases, a meticulous work-up nearly always reveals some disturbance in regards to the metabolism of the lipids-lack of certain lipoproteins, for example. Xanthoma tuberosum and tendinosum occur in persons with familiar hypercholesterolemia, palmar crease xanthoma in familial dysbetalipoproteinemia, plane xanthoma in persons with an underlying lymphoproliferative disorder (or normolipemic), and eruptive xanthoma in those with a genetically-transmitted lipoprotenemia. In sum, each type of xanthoma and any associated abnormality in lipid metabolism can be diagnosed with specificity. Xanthomas are deposits of lipid in the skin or subcutaneous tissue that manifest clinically as yellowish papules, nodules and tumors. They are often associated with hyperlipidemias, although some of them may be normolipemic. Xanthomas result when abnormalities in the transportation of lipids such as cholesterol, triglycerides and phospholipids cause these lipids to be deposited in the skin and being ingested by tissue macrophages. When they are deposited in the walls of arteries, they promote the development of atherosclerosis. Sometimes, by identifying the clinical variant of the xanthoma, the lipoprotein that is deposited and the clinical associations can be predicted. This discussion will focus on those xanthomas associated with hyperlipidemias.
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PMID:Xanthomas: a marker for hyperlipidemias. 1503 23

Familial hypercholesterolemia is an autosomal-dominant inherited disorder caused by mutations in the low-density lipoprotein (LDL) receptor gene. The homozygous form is characterized by high-serum LDL cholesterol concentrations, xanthoma formation and premature atherosclerosis. Recently, another molecular defect that also results in severely elevated LDL cholesterol levels was identified: autosomal recessive hypercholesterolemia. This inherited disorder is caused by a mutation in a putative LDL receptor adaptor protein. In our lipid clinic, three sisters with phenotypic homozygous hypercholesterolemia were recently diagnosed as having autosomal recessive hypercholesterolemia. They presented in 1990 with massive tuberous xanthomas at the knees, thighs, elbows and buttocks. LDL receptor and apolipoprotein B gene defects were excluded through mutation analysis. From 1992 onward they underwent LDL-apheresis on a weekly basis. To date the clinical outcome is very satisfying with no evidence of coronary heart disease or aortic valve lesions and almost complete regression of xanthomatosis.
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PMID:Autosomal recessive hypercholesterolemia in three sisters with phenotypic homozygous familial hypercholesterolemia: diagnostic and therapeutic procedures. 1527 77

Many factors play a role in the development of atherosclerotic lesions. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia (FH). FH is a genetic disease characterized by a deficiency, and/or mutation, of receptors for low density lipoprotein (LDL) on the plasmalemma of endothelial cells (EC), a high level of low density lipoprotein in the plasma, and early, spontaneous development of atherosclerosis and skin xanthoma. In this review we describe Watanabe heritable hyperlipidemic (WHHL) rabbits, which represent such an animal model for human FH. This strain of the rabbits is characterized by a genetic deficiency or mutation of functional LDL receptors and develops severe atherosclerosis, which is pathologically similar to familial homozygous hyperlipidemic patients. The most completely characterized animal model is the Watanabe rabbit, a model of homozygous and heterozygous type IIa hypercholesterolemia related to an LDL receptor deficiency. Additional manipulation such as aortic injury in this rabbit model induces the development of atherosclerotic lesions that are structurally similar to those found in humans. Thus, this model of hypercholesterolemia fulfils the above criteria set, i.e. it is able to provide new insights for a better understanding of the pathogenesis of atherosclerosis and for testing new treatment strategies.
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PMID:Pathobiology of familial hypercholesterolemic atherosclerosis. 1590 97

Familial hypercholesterolemia (FH) is a common single gene disorder, which predisposes to coronary artery disease. In a previous study, we have shown that in patients with definite FH around 20% had no identifiable gene defect after screening the entire exon coding area of the low density lipoprotein receptor (LDLR) and testing for the common Apolipoprotein B (ApoB) R3500Q mutation. In this study, we have extended the screen to additional families and have included the non-coding intron splice regions of the gene. In families with definite FH (tendon xanthoma present, n=68) the improved genetic screening protocol increased the detection rate of mutations to 87%. This high detection rate greatly enhances the potential value of this test as part of a clinical screening program for FH. In contrast, the use of a limited screen in patients with possible FH (n=130) resulted in a detection rate of 26%, but this is still of significant benefit in diagnosis of this genetic condition. We have also shown that 14% of LDLR defects are due to splice site mutations and that the most frequent splice mutation in our series (c.1845+11 c>g) is expressed at the RNA level. In addition, DNA samples from the patients in whom no LDLR or ApoB gene mutations were found, were sequenced for the NARC-1 gene. No mutations were identified which suggests that the role of NARC-1 in causing FH is minor. In a small proportion of families (<10%) the genetic cause of the high cholesterol remains unknown, and other genes are still to be identified that could cause the clinical phenotype FH.
Atherosclerosis 2005 Oct
PMID:Genetic screening protocol for familial hypercholesterolemia which includes splicing defects gives an improved mutation detection rate. 1615 6


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