UMLS:C0004153 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Target Concepts:

Query: UMLS:C0004153 (atherosclerosis)
77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Familial combined hyperlipidemia (FCHL) is a common inherited hyperlipidemia and a major risk factor for atherothrombotic cardiovascular disease. The cause(s) leading to FCHL are largely unknown, but the existence of unidentified "major" genes that would increase VLDL production and of "modifier" genes that would influence the phenotype of the disease has been proposed. Expression of apolipoprotein A-II (apoA-II), a high density lipoprotein (HDL) of unknown function, in transgenic mice produced increased concentration of apoB-containing lipoproteins and decreased HDL. Here we show that expression of human apoA-II in apoE-deficient mice induces a dose-dependent increase in VLDL, resulting in plasma triglyceride elevations of up to 24-fold in a mouse line that has 2-fold the concentration of human apoA-II of normolipidemic humans, as well as other well-known characteristics of FCHL: increased concentrations of cholesterol, triglyceride, and apoB in very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL) and low density lipoprotein (LDL), reduced HDL cholesterol, normal lipoprotein lipase and hepatic lipase activities, increased production of VLDL triglycerides, and increased susceptibility to atherosclerosis. However, FCHL patients do not have plasma concentrations of human apoA-II as high as those of apoE-deficient mice overexpressing human apoA-II, and the apoA-II gene has not been linked to FCHL in genome-wide scans. Therefore, the apoA-II gene could be a "modifier" FCHL gene influencing the phenotype of the disease in some individuals through unkown mechanisms including an action on a "major" FCHL gene. We conclude that apoE-deficient mice overexpressing human apoA-II constitute useful animal models with which to study the mechanisms leading to overproduction of VLDL, and that apoA-II may function to regulate VLDL production.
...
PMID:Expression of human apolipoprotein A-II in apolipoprotein E-deficient mice induces features of familial combined hyperlipidemia. 1094 21

Chitotriosidase, an enzyme involved in the degradation of chitin-containing pathogens with unclear function in humans, has been proposed as a marker of lipid accumulation in macrophages in different lipid-storage diseases, including atherosclerosis. To evaluate (1) if lipid-lowering treatment could modify serum chitotriosidase activity and (2) be useful in monitoring lipid-lowering treatment, we have analyzed this enzyme activity in the participants in the Atozvastatin Versus Bezafibrate in Mixed Hyperlipidemia (ATOMIX) study, a double-blind, comparative, and randomized study comparing the efficacy of atorvastatin and bezafibrate in mixed hyperlipidemia. Because a common genetic deficiency of chitotriosidase modifies serum quitotriosidase activity, this genetic variation was also studied. Seven subjects of 116 (6.03%) were homozygous, and 46 (39.6%) were heterozygous for the defective allele. Mean serum quitotriosidase activity correlated with allele dosage, as it was found to be of 0, 59.8 +/- 52.6 and 81.2 +/- 41.6 nmol/mL/h, in homozygotes for the defective allele, heterozygotes, and homozygotes for the wild-type allele, respectively (P =.0011 for the difference between the last 2 groups). However, this enzyme activity was not found to correlate with lipid levels before and after treatment with either atorvastatin or bezafibrate, and neither with the intensity of the lipid lowering. These results do not support the use of serum chitotriosidase activity as a biologic marker of atherosclerotic plaque modification related to hypolipidemic treatment.
...
PMID:Chitotriosidase genotype and serum activity in subjects with combined hyperlipidemia: effect of the lipid-lowering agents, atorvastatin and bezafibrate. 1128 40

An elevated plasma apolipoprotein B (apoB) level is a strong predictor of atherosclerosis and coronary heart disease. Epidemiologic and family linkage studies have suggested a genetic basis for the wide variations of plasma apoB levels in the general population. Using a human apoB transgenic (HuBTg) mouse model, we have previously shown that hepatic apoB-100 secretion is a major determinant of the high and low plasma human apoB levels in HuBTg mice of the C57BL/6 (B6) and 129/Sv (129) strains, respectively. In the present article, we present the identification of two novel quantitative trait loci (QTL) as major regulators of plasma human apoB levels in the F(2) and N(2) (backcrossed) offspring (n = 572) derived from crosses between the B6 and 129 mouse strains. These loci were designated ApoB regulator genes (Abrg), because the gene products are likely to be involved in the regulation of plasma apoB levels either directly or indirectly. The first locus, designated Abrg1, was mapped to chromosome 6 in 8-week-old male and female mice with a combined logarithm of odds ratio (LOD) score of 14 at the D6Mit55 marker ( approximately 45.9 cM). Abrg1 contributed approximately 35% of the genetic variance. The second locus, designated Abrg2, was mapped to chromosome 4 with an LOD score of 8.6 in 8-week-old male mice but an LOD score of only 2.0 in 8-week-old female mice at the D4Mit27 marker ( approximately 35 cM). Abrg2 contributed approximately 26% of the genetic variance. Epistasis between Abrg1 and Abrg2 was detected and accounted for approximately 12% of the genetic variance. The combination of these two QTL has major effects (>70%) on the regulation of plasma human apoB levels in the tested population. In summary, we have identified two novel loci that have a major role in the regulation of plasma apoB levels and are likely to regulate the secretory pathway of apoB. The human orthologs for the Abrg loci are strong candidates for human disorders characterized by altered plasma apoB levels, such as FCHL and familial hypobetalipoproteinemia.
...
PMID:Two novel quantitative trait loci on mouse chromosomes 6 and 4 independently and synergistically regulate plasma apoB levels. 1135 92

Familial combined hyperlipidemia (FCH) is characterised by hypercholesterolemia and/or hypertriglyceridemia and associated with an increased risk of cardiovascular disease (CVD). The plasma lipid and lipoprotein levels in subjects with FCH are relatively moderately elevated and do not fully explain the increased risk of CVD. Hyperhomocysteinemia is a disorder of methionine metabolism and also a well-known independent risk factor for CVD. We investigated whether subjects with FCH have higher plasma homocysteine concentrations than controls, and whether homocysteine contributes to the increased risk of CVD in FCH. Furthermore we evaluated whether parameters of lipid and lipoprotein metabolism and/or insulin resistance are associated with the homocysteine level. In total 667 subjects, including 161 subjects with FCH, 109 spouses who referenced as control group and 397 normolipidemic relatives were studied. FCH was defined by the presence of plasma total cholesterol and/or triglyceride levels above the 90th percentile adjusted for age and gender. The mean homocysteine concentration of the FCH group did not significantly differ from the control group. The risk for CVD due to hyperhomocysteinemia in subjects with FCH was not higher than in subjects without FCH. No associations were observed between plasma homocysteine concentration and plasma lipid and lipoprotein levels, including small dense low density lipoprotein, nor between homocysteine concentration and insulin resistance.
Atherosclerosis 2003 Jan
PMID:Plasma homocysteine in subjects with familial combined hyperlipidemia. 1248 57

FCHL (familial combined hyperlipidaemia) is the most frequent inherited disorder of lipid metabolism leading to premature atherosclerosis. The usual phenotype in FCHL is elevated fasting plasma triacylglycerols, low HDL (high-density lipoprotein)-cholesterol concentrations and elevated plasma apolipoprotein B concentrations. The metabolic basis for this phenotype is hepatic overproduction of VLDL (very-low-density lipoprotein), which is only partly linked to the insulin resistance associated with FCHL. At this stage the molecular basis for this VLDL overproduction is not known, but emerging evidence points to a disturbed trapping of peripheral fatty acids, resulting in enhanced hepatic flux of NEFA [non-esterified ('free') fatty acids]. Postprandial hyperlipidaemia with accumulation of lipoprotein remnants and NEFA have been implicated in the development of atherosclerosis in this disorder. It has been proposed that, by VLDL overproduction, fasting hypertriglyceridaemia may lead to 'overflow' of the catabolic cascade for triacylglycerol-rich particles, thereby explaining the delayed catabolism of remnants in FCHL. Delayed clearance of remnants of VLDL and chylomicrons leads to enhanced interaction of these highly atherogenic particles with the endothelium, and enhanced trans-endothelial migration of the particles, resulting in a chronic inflammatory response that is the initiation of the atherosclerotic lesion. In this process, activated leucocytes (either directly by the remnants or indirectly by released NEFA) play an important role by adherence to the endothelium and migration into the subendothelial space, where the uptake of atherogenic remnants results in a vicious cycle of activation of endothelium, leucocytes and production of cytokines.
...
PMID:Postprandial lipaemia in familial combined hyperlipidaemia. 1450 86

Familial combined hyperlipidemia (FCHL) is characterized by elevated levels of serum total cholesterol (TC), triglyceride (TG), or both. The increased incidence of coronary artery diseases (CAD) in the patients with FCHL is believed to be caused by circulating atherogenic lipoproteins associated with the complex phenotype. Recent establishment of sensitive detection system for malondialdehyde-modified (MDA)-LDL, which is one of oxidized lipoproteins, showed its increased circulating level in the patients with CAD. In order to know the atherogenic lipoproteins resulted from the dyslipidemia observed in FCHL, we measured the serum MDA-LDL level in the patients. The circulating MDA-LDL level and the ratio of MDA-LDL and LDL-C in FCHL were significantly higher (P<0.05) than those in control, which are adjusted about the age, serum TC, LDL-C and HDL-C levels, respectively. Furthermore, the circulating MDA-LDL level and the ratio of MDA-LDL and LDL-C were negatively correlated (R=-0.635, P<0.01 and R=-0.702, P<0.01, respectively) with hepatic lipase (HL) activity in FCHL. The serum MDA-LDL level and the ratio of MDA-LDL and LDL-C were in the subjects with T/T genotypes in the HL C-514T polymorphism were significantly increased compared to those with C/C genotype, respectively. The subjects with T/T genotype showed the activities to 65 and 79% of those in the subjects with C/C genotype in male and female, respectively. The intima-media thickness (IMT) of carotid artery was significantly higher (P<0.05) in the subjects with T/T genotype than those with C/C genotype in male. These findings indicate that the circulating MDA-LDL level is possibly contributing the atherogenic process in FCHL, and the common HL polymorphism might be a determinant of the serum level of oxidized LDL in the patients with FCHL.
Atherosclerosis 2004 Jan
PMID:Increased circulating malondialdehyde-modified LDL in the patients with familial combined hyperlipidemia and its relation with the hepatic lipase activity. 1470 74

Familial combined hyperlipidemia (FCHL) is the most common familial dyslipidemia, and is implicated in up to 20% of cases of premature coronary heart disease. Positive linkage to chromosome 1q was found in FCHL families participating in the NHLBI Family Heart Study (FHS), replicating linkage found in other studies. The HcB-19 mouse, which shares phenotypes with FCHL, was shown in other studies to have a nonsense mutation in the thioredoxin interacting protein gene (txnip). txnip is a gene on mouse chromosome 3 in a region syntenic with the 1q human FCHL linkage region. We re-sequenced the human homolog of mouse txnip in the FHS sample and identified nine single nucleotide polymorphisms (SNPs). We did not observe the nonsense mutation found in the HcB-19 mouse, and only three of the SNPs discovered were sufficiently polymorphic for analysis. No association between FCHL and the TXNIP gene was found. Within FCHL cases, presence of variants also did not significantly affect body mass index or levels of lipids, insulin, or glucose. Our results suggest that in this sample, TXNIP does not play a major role in FCHL or related traits, and is unlikely to account for the positive evidence of linkage in this region.
Atherosclerosis 2004 Jun
PMID:TXNIP gene not associated with familial combined hyperlipidemia in the NHLBI Family Heart Study. 1513 67

Familial combined hyperlipidaemia (FCHL) is a complex genetic disorder of unknown aetiology. Study of this human condition over many decades has been hampered by likely genetic heterogeneity. In order to find better phenotypic markers, we have characterised the structures of VLDL, IDL and LDL in the St. Thomas' Mixed Hyperlipidaemic (SMHL) rabbit--an animal model of FCHL in which the hyperlipidaemia is caused primarily by an increased production rate of apolipoprotein B (apoB)--containing lipoproteins-and compared them with those in the Watanabe Heritable Hyperlipidaemic (WHHL) rabbit, in which hyperlipidaemia is caused mainly by a defect in lipoprotein clearance, and those in the normolipidaemic New Zealand White (NZW) animal. All three rabbit strains were fed a cholesterol-enriched (0.08%, w/w) diet for at least 3 months prior to blood sampling. Both SMHL and WHHL rabbits showed combined hyperlipidaemia as evidenced by significantly increased levels of plasma cholesterol and triglycerides. Raised plasma lipids in the SMHL rabbit were attributable mainly to an overabundance of lipoprotein particles with the same lipid composition as those in NZW rabbits. VLDL and IDL in the SMHL rabbit showed a significantly increased sphingomyelin to phosphatidyl choline ratio. In the WHHL rabbit there was a high concentration of particles that were significantly enriched in cholesteryl esters and depleted in triglycerides. Phospholipids in all lipoprotein fractions from WHHL rabbits contained significantly more sphingomyelin and less phosphatidyl choline resulting in a significantly increased sphingomyelin to phosphatidyl choline ratio. We found that the VLDL of SMHL rabbits could be distinguished from that of NZW rabbits on the basis of the cholesterol:apoB and the sphingomyelin:phosphatidylcholine ratios, and from that of WHHL rabbits by the sphingomyelin:triglyceride ratio. Extrapolating these findings to the human condition, an assessment of particle core composition, together with the proportion of sphingomyelin in phospholipids especially in VLDL might help in the differentiation of the combined hyperlipidaemia of FCHL into disorders of lipoprotein overproduction versus decreased clearance.
Atherosclerosis 2005 Jul
PMID:Characterisation of the lipoprotein structure in the St. Thomas' Mixed Hyperlipidaemic (SMHL) rabbit. 1593 55

Familial combined hyperlipidemia (FCH) is characterized by increased levels of total cholesterol, triglycerides, and/or apolipoprotein B. Other features of FCH are obesity and insulin resistance. Adiponectin is a secretory product of the adipose tissue. Low levels of adiponectin are associated with insulin resistance and accelerated atherosclerosis. The aim of this study was to determine whether decreased adiponectin levels are associated with FCH and its phenotypes. The study population comprised 644 subjects, including 158 patients with FCH. Serum adiponectin levels were determined using a commercially available ELISA. For both males and females, the mean adiponectin level (microg/ml) was significantly lower in FCH patients [2.0 (1.8-2.2) and 2.5 (2.3-2.8), respectively] compared with normolipidemic relatives [2.3 (2.2-2.5) and 3.1 (2.8-3.3), respectively] and spouses [2.4 (2.1-2.7) and 3.2 (2.8-3.6), respectively]. These differences remain significant after adjusting for waist circumference and insulin resistance. Low adiponectin level in FCH patients was a superior independent predictor of the atherogenic lipid profile, including high triglyceride levels, low HDL-cholesterol levels, and the amount of small, dense LDL present, compared with both obesity and insulin resistance. Low adiponectin levels may contribute to the atherogenic lipid profile in FCH, independent of insulin resistance and obesity, as measured by waist circumference. This finding implies a role of adipose tissue metabolism in the pathophysiology of FCH.
...
PMID:Decreased adiponectin levels in familial combined hyperlipidemia patients contribute to the atherogenic lipid profile. 1610 49

Familial combined hyperlipidemia (FCH) is the most common familial hyperlipidemia with a high risk for early atherosclerosis. The aim of this study was to compare levels of soluble intercellular cell adhesion molecule 1 (s-ICAM-1) and soluble vascular cell adhesion molecule 1 (s-VCAM-1) in asymptomatic members of FCH families with healthy controls and to determine the relation between s-ICAM-1, s-VCAM-1 and risk factors accompanying FCH. We also investigated the association between adhesion molecules and the intima-media thickness (IMT) of the common carotid artery, a recognized morphological marker of early atherosclerosis. 82 members of 29 FCH families were divided into the 2 groups: HL (probands and hyperlipidemic first-degree relatives, n = 47) and NL (normolipidemic first-degree relatives, n = 35). The control groups--HL-C (n = 20) and NL-C (n = 20)--consisted of sex- and age-matched healthy individuals. Hyperlipidemic members had significantly higher concentration of s-ICAM-1 (633.7 +/- 169.6 ng/ml versus 546.2 +/- 155.9 ng/ml, p < 0.05). The elevation of s-VCAM-1 was not significant (880.8 +/- 202.9 ng/ml versus 826.5 +/- 174.6 ng/ml, N.S.). Levels of s-ICAM-1 and of s-VCAM-1 in normolipidemic relatives were not significantly different from the control group (530.8 +/- 113.9 ng/ml versus 530.0 +/- 101.0 ng/ml and 860.2 +/- 265.7 ng/ml versus 822.1 +/- 197.0 ng/ml respectively). There was a significant correlation between s-ICAM-1 and apoB (r = 0.42; p < 0.01) in hyperlipidemic subjects and between s-ICAM-1 and proinsulin (r = 0.54; p < 0.01) in normolipidemic subjects. S-ICAM-1 correlated with IMT (r = 0.32; p < 0.05) in all members of FCH families. The increase of s-ICAM-1 in asymptomatic hyperlipidemic members of FCH families reflects their high cardiovascular risk. The positive association between s-ICAM-1 and IMT could indicate s-ICAM-1 as a potential predictor of atherosclerosis manifestation.
...
PMID:Soluble cell adhesion molecules s-VCAM-1 and s-ICAM-1 in subjects with familial combined hyperlipidemia. 1617 Mar 96

<< Previous 1 2 3 4 Next >>