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)

Because total cholesterol levels have been found to be lower in patients affected by thalassemia major and intermedia, we examined the plasma lipid pattern of 628 beta-thalassemia trait carriers and 4552 controls in order to evaluate whether the plasma lipid impairment is also present in the heterozygous state. Total cholesterol and low density lipoprotein (LDL)-cholesterol levels were significantly lower in beta-thalassemia trait carriers when compared to controls, whereas plasma triglycerides and high density lipoprotein (HDL)-cholesterol levels did not differ between the two groups. We suggest that accelerated erythropoiesis and increased uptake of LDL by macrophages and histiocytes of the reticuloendothelial system are the main determinants of low plasma cholesterol levels in heterozygous thalassemia.
Atherosclerosis 1989 Feb
PMID:Plasma lipids in beta-thalassemia minor. 271 66

Patients with homozygous beta-thalassemia show an abnormal lipoprotein profile. In asymptomatic heterozygotes the lipid pattern is less markedly affected but interestingly related to a diminished cardiovascular risk. The extent and significance of these findings are still a matter of debate and no data are available on lipoprotein(a) plasma levels. Seventy patients with homozygous beta-thalassemia (HT-P), 70 beta-thalassemia trait carriers (TT-C) and 70 sex and age-matched controls were investigated and their plasma lipoprotein profile and apo(a) phenotypes determined. In a subgroup of these same subjects (12 HT-P, 12 TT-C and 24 controls) and in 12 bone marrow-transplanted homozygous beta-thalassemic patients (BMT-P) plasma lipoprotein composition was assessed. HT-P disclosed significantly lower total-cholesterol, LDL-cholesterol, HDL-cholesterol, apo A-I, apo B plasma levels and higher triglyceride concentration than TT-C (-7, -11, -8, -8, -13 and +11%, respectively) or controls (-39, -50, -46, -32, -30 and + 35%, respectively). All lipoprotein subclasses were triglyceride-enriched, while LDLs were also protein-enriched and HDLs protein-depleted. TT-C disclosed a small but significant reduction in apo A-I and apo B plasma levels but only minor lipoprotein abnormalities with respect to the controls. BMT-P lipoprotein composition was intermediate between HT-P and normal subjects. Apo(a) plasma levels did not differ among the groups. A higher prevalence of 'small' apo(a) isoforms was present in HT-P. Within the same 'isoform group', apo(a) plasma levels were significantly lower in HT-P than in TT-C or controls. Since liver cirrhosis is almost always present in HT-P, it is conceivable that an altered hepatic apo(a) synthesis or catabolism due perhaps to diminished apolipoprotein glycation may be involved. In TT-C a partially improved cardiovascular risk profile was apparent (low hematocrit, low LDL-cholesterol and apo B), thus justifying the claim for a low prevalence of ischemic heart disease, but no Lp(a) plasma level modification could be detected.
Atherosclerosis 1997 May
PMID:Plasma lipoprotein composition, apolipoprotein(a) concentration and isoforms in beta-thalassemia. 918 Feb 53

One of the genetic features of the Sardinian population is the high prevalence of hemoglobin disorders. It has been estimated that 13% to 33% of Sardinians carry a mutant allele of the alpha-globin gene (alpha-thalassemia trait) and that 6% to 17% are beta-thalassemia carriers. In this population, a single mutation of beta-globin gene (Q39X, beta(0) 39) accounts for >95% of beta-thalassemia cases. Because previous studies have shown that Sardinian beta-thalassemia carriers have lower total and low density lipoprotein (LDL) cholesterol than noncarriers, we wondered whether this LDL-lowering effect of the beta-thalassemia trait was also present in subjects with familial hypercholesterolemia (FH). In a group of 63 Sardinian patients with the clinical diagnosis of FH, we identified 21 unrelated probands carrying 7 different mutations of the LDL receptor gene, 2 already known (313+1 g>a and C95R) and 5 not previously reported (D118N, C255W, A378T, T413R, and Fs572). The 313+1 g>a and Fs572 mutations were found in several families. In cluster Fs572, the plasma LDL cholesterol level was 5.76+/-1.08 mmol/L in subjects with beta(0)-thalassemia trait and 8.25+/-1.66 mmol/L in subjects without this trait (P<0.001). This LDL-lowering effect was confirmed in an FH heterozygote of the same cluster who had beta(0)-thalassemia major and whose LDL cholesterol level was below the 50th percentile of the distribution in the normal Sardinian population. The hypocholesterolemic effect of beta(0)-thalassemia trait emerged also when we pooled the data from all FH subjects with and without beta(0)-thalassemia trait, regardless of the type of mutation in the LDL receptor gene. The LDL-lowering effect of beta(0)-thalassemia may be related to (1) the mild erythroid hyperplasia, which would increase the LDL removal by the bone marrow, and (2) the chronic activation of the monocyte-macrophage system, causing an increased secretion of some cytokines (interleukin-1, interleukin-6, and tumor necrosis factor-alpha) known to affect the hepatic secretion and the receptor-mediated removal of apolipoprotein B-containing lipoproteins. The observation that our FH subjects with beta(0)-thalassemia trait (compared with noncarriers) have an increase of blood reticulocytes (40%) and plasma levels of interleukin-6 (+60%) supports these hypotheses. The lifelong LDL-lowering effect of beta(0)-thalassemia trait might slow the development and progression of coronary atherosclerosis in FH.
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PMID:Influence of beta(0)-thalassemia on the phenotypic expression of heterozygous familial hypercholesterolemia : a study of patients with familial hypercholesterolemia from Sardinia. 1063 24

Familial hypercholesterolemia (FH) is a codominant disorder due to a variety of mutations of the low-density lipoprotein (LDL) receptor gene that result in an elevation of plasma LDL-cholesterol (LDL-C). Plasma levels of LDL-C show large interindividual variation even in subjects carrying the same mutation of the LDL receptor gene. This variability may be due to genetic factors (modifier genes). Several surveys indicate that the overall contribution of common polymorphisms of modifier genes (such as the genes encoding apolipoproteins E and B) to this variability is less than 10%. In contrast, beta-thalassemia has a profound LDL-lowering effect. This was documented in FH patients identified on the island of Sardinia, in Italy, where 12% of the inhabitants are carriers of beta-thalassemia due to a single mutation (Q39X) of the beta-globin gene that abolishes the synthesis of beta-globin chain of hemoglobin (beta(o)-thalassemia). Plasma LDL-C in FH heterozygotes carrying the beta(o)-thalassemia trait is 25% lower than in noncarriers, regardless of the LDL receptor gene mutation. It is likely that this effect is due to two main mechanisms: (1) increased uptake of LDL by the bone marrow to provide cholesterol for the increased proliferation of erythroid progenitor cells and (2) increased production of inflammatory cytokines that reduce the hepatic secretion and increase the catabolism of LDL. In view of its LDL-C-lowering effect, beta-thalassemia trait may protect FH heterozygotes against premature coronary atherosclerosis.
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PMID:Beta-thalassemia is a modifying factor of the clinical expression of familial hypercholesterolemia. 1563 Jun 28

We report a 33-year-old Malay woman presented with acute left dense hemiparesis and an NIHSS score of 11/15. Computed tomography (CT) scan brain showed a massive right middle cerebral artery (MCA) territory infarct. The right internal carotid artery (ICA) and right proximal MCA were shown occluded from digital substraction angiography (DSA). Carotid dissection, carotid canal anomaly, and intercavernous communication were systematically ruled out. She had no risk factors for atherosclerosis. The connective tissue screening and thrombophilic markers were negative. However, she was anaemic on admission and subsequent investigations revealed that she had alpha-thalassemia and iron deficiency anaemia. The right ICA remained occluded from a repeat CT cerebral angiogram after one year, but otherwise she was neurologically stable. This case illustrates an unusual association between intracranial vessel occlusion with iron deficiency anaemia and alpha-thalassemia trait.
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PMID:An Unusual Association between Unilateral Intracranial Vessels Occlusion with Iron Deficiency Anaemia and Alpha-Thalassemia Trait: A Case Report. 2222 36