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E J Schaefer

Publications and source records attributed to E J Schaefer.

At least 19 recordsLinked to original sources
PubMed2002

Association between the PPARA L162V polymorphism and plasma lipid levels: the Framingham Offspring Study.

Peroxisome proliferator activated receptor (PPAR) alpha is a member of the nuclear receptor superfamily that regulates key proteins involved in fatty acid oxidation, extracellular lipid metabolism, hemostasis, and inflammation. A L162V polymorphism at the PPARA locus has been associated with alterations in lipid and apolipoprotein concentrations. We studied the association among lipids, lipoproteins, and apolipoproteins and the presence of the L162V polymorphism in 2373 participants (1128 men and 1244 women) in the Framingham Offspring Study. The frequency of the less common allele (V162) was 0.069. The V162 allele was associated with increased serum concentrations of total and LDL cholesterol in men (P=0.0012 and P=0.0004, respectively) and apolipoprotein B in men (P=0.009) and women (P=0.03 after adjustment for age, body mass index, smoking, and use of beta-blockers, diuretics or estrogens). Apolipoprotein (apo) C-III concentrations were higher in carriers of the V162 allele. The association of the L162V polymorphism on LDL cholesterol concentration was greatest in those who also carried the E2 allele at the APOE locus and the G allele at the APOC3 3238C>G polymorphism. This suggests that alterations in triglyceride-rich lipoprotein metabolism may be involved in the generation of the increase in LDL cholesterol observed with the L162V PPARA polymorphism.

Amino Acid Substitution↗
PubMed2002

Effects of apolipoprotein A-I genetic variations on plasma apolipoprotein, serum lipoprotein and glucose levels.

The present authors investigated the individual and combined associations of the apolipoprotein (apo) A-I -75 bp and +83 bp polymorphisms with plasma lipid, lipoprotein and apolipoprotein levels in 734 Caucasian men and women. The frequency of the A allele at position -75 bp (G-->A) was 0.14 in women and 0.17 in men. The frequencies for the rare M2 allele at position +83 bp and/or 84 bp (C-->T and G-->A, respectively) were 0.04 and 0.05 in women and men, respectively. In women, the A allele was associated with significantly higher levels of apo B (P = 0.016), total cholesterol (TC) (P = 0.005), low-density lipoprotein cholesterol (LDL-C) (P = 0.018) and TC:high-density lipoprotein (HDL) ratio (P = 0.026) compared to the G/G subjects. In men, no significant associations were detected between the -75 bp polymorphism and any lipid trait examined. The M2 allele for the +83 bp polymorphism was significantly associated in men with higher levels of apo A-I (P = 0.002) and TC (P = 0.046). In women, a significant effect was observed for TC (P = 0.036), with M2+/- subjects having lower levels than M2+/+ subjects. Significant linkage disequilibrium (P = 0.037) between the apo A-I -75 bp and +83 bp polymorphisms was detected. Women carrying both rare alleles (G/A M2+/-) had significantly higher TC:HDL ratios (P = 0.031) compared to the other haplotypes. In men, significant differences were observed for apo A-I (P = 0.021) and TC (P = 0.044), with carriers of the G/G M2+/- haplotype having the highest values compared to other genotype combinations. In conclusion, the -75 bp (G/A) polymorphism appears to have a significant effect on levels of apo B, plasma TC and LDL-C in women, while the +83 bp polymorphism seems to affect the apo A-I levels in men, and the plasma cholesterol levels in both genders.

Apolipoprotein A-I↗
PubMed2002

Two novel mutations in the sterol 27-hydroxylase gene causing cerebrotendinous xanthomatosis.

Cerebrotendinous xanthomatosis (CTX) is a rare recessive autosomal disease caused by mutations of the sterol 27-hydroxylase gene. Clinically, CTX is characterized by tendon xanthomas, cataracts and progressive neurological deficits. Because of the disruption of the 27-hydroxylase activity, CTX patients have elevated plasma levels of cholestanol, a by-product of abnormal bile acid synthesis. The present authors describe a female patient with CTX. The proband in this study presented with elevated cholestanol levels, markedly reduced mitochondrial 27-hydroxylase activity and altered bile acid composition. The 27-hydroxylase gene was analysed for mutations by polymerase chain reaction amplification of the exons and the splice-junction regions of the gene. The proband was found to be a compound heterozygote for two different mutations which have not been previously described: (1) a G --> A transition at nucleotide 455 that is responsible for converting a glycine to a glutamic acid residue at amino acid position 112 (G112E); and (2) a five-nucleotide deletion in exon 5 (from nucleotide 965 to 969) that is responsible for a shift in the reading frame and the insertion of a premature codon at position 296, and consequently, the synthesis of a truncated protein lacking the heme-binding and andrenodoxin-binding domains. Long-term (18-year) treatment of the proband with chenodeoxycholic acid (750 mg day-1) has been effective in preventing any progression of the disease.

Amino Acid Substitution↗
PubMed2001

Comparison of fasting and postprandial plasma lipoproteins in subjects with and without coronary heart disease.

Plasma lipoprotein levels, including remnant-like particle (RLP) cholesterol and RLP triglycerides, were assessed in fasting (12 hours) and postprandial (PP) (4 hours after a fat-rich meal) states in 88 patients with coronary heart disease (CHD) and 88 controls. All lipoproteins were assessed by direct methods. We hypothesized that patients with CHD would have greater percent increases in their triglyceride levels, RLP cholesterol, and RLP triglycerides, in response to a fat-rich meal. In the fasting state, triglycerides, RLP cholesterol, RLP triglycerides, and low-density lipoprotein (LDL) cholesterol levels were all significantly higher in cases versus controls by 51%, 35%, 39%, and 40%, respectively. These levels were 57%, 37%, 64%, and 37% higher in the PP state, respectively. Mean high-density lipoprotein (HDL) cholesterol values were 27% lower in cases in both the fasting and PP states. After eating, triglycerides, RLP cholesterol, and RLP triglycerides increased 64%, 71%, and 290% in controls, respectively, whereas in cases these levels increased by 71%, 94%, and 340%, respectively (all p <0.0001). Percent increases in the PP state were not significantly different in cases versus controls. Following the fat-rich meal, LDL and HDL cholesterol decreased by 5% and 4% in controls, and by 7% and 6% in patients, with no significant difference in percent changes between groups. Fasting values correlated very highly with PP values for all parameters (all p <0.0001). Our data indicate that although patients with CHD have higher fasting and PP levels of triglycerides, RLP cholesterol, and RLP triglycerides than controls, the response (percent increase) to a fat-rich meal is comparable in both groups. Thus, a feeding challenge is not essential for assessment of these lipoproteins. Moreover, it is not necessary to obtain a fasting sample to assess direct LDL and HDL cholesterol.

Body Mass Index↗
PubMed2001

Effect of niacin and atorvastatin on lipoprotein subclasses in patients with atherogenic dyslipidemia.

This study was conducted to determine the efficacy of atorvastatin and niacin on lipoprotein subfractions in patients with atherogenic dyslipidemia. This was a multicenter, randomized, open-label, parallel-design study of patients with total cholesterol >200 mg/dl, triglycerides between 200 and 800 mg/dl, and apolipoprotein B >110 mg/dl. Patients were randomly assigned to atorvastatin 10 mg or immediate release niacin 3,000 mg daily for 12 weeks following a low-fat diet stabilization period. Lipoprotein subclasses were measured by nuclear magnetic resonance spectroscopy. Atorvastatin and niacin both significantly reduced the concentrations of very low-density lipoprotein (VLDL) particles (-31% and -29%, respectively) and small low-density lipoprotein (LDL) particles (-44% and -35%, respectively). Niacin increased the concentration of large LDL (+75%). Atrovastatin reduced the number of LDL particles more than niacin (31% vs 14%). In patients with atherogenic dyslipidemia, both drugs had important effects on lipoprotein subfractions, which contributed to a reduction in coronary heart disease risk. The drugs equally reduced VLDL subclass levels. Niacin shifted the LDL subclass distribution toward the larger particles, more effectively converted patients from LDL phenotype B to phenotype A, and increased levels of the larger and perhaps more cardioprotective high-density lipoprotein particles. In contrast, atorvastatin preferentially lowered the concentration of small LDL particles without increasing levels of large LDL, and more effectively, reduced LDL particle numbers. Atorvastatin had a preferred LDL effect, whereas niacin had a preferred high-density lipoprotein effect.

Anticholesteremic Agents↗
PubMed2001

Relation of gemfibrozil treatment and lipid levels with major coronary events: VA-HIT: a randomized controlled trial.

CONTEXT: A low plasma level of high-density lipoprotein cholesterol (HDL-C) is a major risk factor for coronary heart disease (CHD). A secondary prevention study, the Veterans Affairs High-Density Lipoprotein Intervention Trial (VA-HIT), demonstrated that CHD events were significantly reduced during a median follow-up of 5.1 years by treating patients with the fibric acid derivative gemfibrozil when the predominant lipid abnormality was low HDL-C. OBJECTIVE: To determine if the reduction in major CHD events with gemfibrozil in VA-HIT could be attributed to changes in major plasma lipid levels. DESIGN: Multicenter, randomized, double-blind, placebo-controlled trial conducted from September 1991 to August 1998. SETTING: The Department of Veterans Affairs Cooperative Studies Program, in which 20 VA medical centers were participating sites. PARTICIPANTS: A total of 2531 men with a history of CHD who had low HDL-C levels (mean, 32 mg/dL [0.83 mmol/L] ) and low low-density lipoprotein cholesterol (LDL-C) levels (mean, 111 mg/dL [2.88 mmol/L]). INTERVENTION: Participants were randomly assigned to receive gemfibrozil, 1200 mg/d (n = 1264), or matching placebo (n = 1267). MAIN OUTCOME MEASURE: Relation of lipid levels at baseline and averaged during the first 18 months of gemfibrozil treatment with the combined incidence of nonfatal myocardial infarction and CHD death. RESULTS: Concentrations of HDL-C were inversely related to CHD events. Multivariable Cox proportional hazards analysis showed that CHD events were reduced by 11% with gemfibrozil for every 5-mg/dL (0.13-mmol/L) increase in HDL-C (P =.02). Events were reduced even further with gemfibrozil beyond that explained by increases in HDL-C values, particularly in the second through fourth quintiles of HDL-C values during treatment. During gemfibrozil treatment, only the increase in HDL-C significantly predicted a lower risk of CHD events; by multivariable analysis, neither triglyceride nor LDL-C levels at baseline or during the trial predicted CHD events. CONCLUSIONS: Concentrations of HDL-C achieved with gemfibrozil treatment predicted a significant reduction in CHD events in patients with low HDL-C levels. However, the change in HDL-C levels only partially explained the beneficial effect of gemfibrozil.

Cholesterol, HDL↗
PubMed2001

Apolipoprotein E genotype and cardiovascular disease in the Framingham Heart Study.

BACKGROUND: Apolipoprotein (apo) E is a constituent of lipoproteins with considerable variation due to cysteine-arginine exchanges. The apo E4 (Arg112-Cys) polymorphism has been associated with dementia and hypercholesterolemia. We investigated the relation of APOE genotype to cardiovascular disease (CVD) in the Framingham Offspring Study. METHODS AND RESULTS: DNA was isolated from 3413 study participants and APOE genotypes were determined utilizing the polymerase chain reaction and restriction isotyping. In the entire group of subjects, 20.7% had apo E4/4 or E3/4 (Group E4); 14.1% had apo E2/2 or E2/3 (Group E2) and 63.9% had the apo E3/3 genotype (Group E3). Subjects with E2/4 (1.3%) were excluded. Period prevalence of CVD between examinations 1 and 5 (1971-1994) (366 events) was related to APOE genotype. Age adjusted period prevalence of CVD in men was 18.6% for Group E4, 18.2% for Group E2 and 12.7% for Group E3 (P=0.004); while in women these rates were 9.9, 4.9, and 6.6%, respectively (P=0.037). After adjustment for non-lipid risk factors the relative odds for CVD in Group E2 men was 1.79 (P=0.0098) and in Group E4 it was 1.63 (P=0.0086) compared with the Group E3; while in Group E4 women it was 1.56 (P=0.054). After adjustment for all CVD risk factors, the relative odds in Group E2 men was 1.94 (P=0.004) and in Group E4 men it was 1.51 (P=0.0262). CONCLUSIONS: The presence of the apo E2 or apo E4 alleles in men is associated with significantly greater CVD risk. This genotypic information may help to identify individuals at increased risk for CVD events.

Adolescent↗
PubMed2001

Common variants in the gene encoding ATP-binding cassette transporter 1 in men with low HDL cholesterol levels and coronary heart disease.

HDL cholesterol (HDL-C) deficiency is the most common lipid abnormality observed in patients with premature coronary heart disease (CHD). Recently, our laboratory and others demonstrated that mutations in the ATP-binding cassette transporter 1 (ABCA1) gene are responsible for Tangier disease, a rare genetic disorder characterized by severely diminished plasma HDL-C concentrations and a predisposition for CHD. To address the question of whether common variants within the coding sequence of ABCA1 may affect plasma HDL-C levels and CHD risk in the general population, we determined the frequencies of three common ABCA1 variants (G596A, A2589G and G3456C) in men participating in the Veterans Affairs Cooperative HDL Cholesterol Intervention Trial (VA-HIT), a study designed to examine the benefits of HDL raising in men having low HDL-C (< or =40 mg/dl) and established CHD, as well as in CHD-free men from the Framingham Offspring Study (FOS). Allele frequencies (%) in VA-HIT were 31, 16, and 4 for the G596A, A2589G, and G3456C variants, respectively, versus 27, 12, and 2 in FOS (P<0.03). None of the variants were significantly associated with plasma HDL-C concentrations in either population; however, in VA-HIT, the G3456C variant was associated with a significantly increased risk for CHD end points, suggesting a role for this variant in the premature CHD observed in this population.

ATP Binding Cassette Transporter 1↗
PubMed2001

New developments in the prevention of atherosclerosis in patients with low high-density lipoprotein cholesterol.

Epidemiologic studies have established that a low concentration of plasma high-density lipoprotein (HDL) cholesterol is an independent risk factor for coronary heart disease (CHD). In the United States, a low HDL cholesterol concentration is the most prevalent lipid abnormality observed in men with known CHD. Despite this fact, surprisingly few clinical trials have been designed to investigate the effects of pharmacologic agents on HDL cholesterol-raising and CHD risk in large populations, perhaps due, in part, to the lack of available drugs having significant HDL cholesterol-raising potential. The purpose of this report is to review recent primary and secondary prevention trials that have explored the relationships between drug therapy, HDL cholesterol concentration, and CHD events or progression. Emphasis will be placed on the results of the Veterans Affairs High-Density Lipoprotein Trial, a study that was specifically designed to test the hypothesis that HDL cholesterol-raising with gemfibrozil would reduce CHD morbidity and mortality in patients with CHD whose primary lipid abnormality was a low level of HDL cholesterol.

Cholesterol, HDL↗
PubMed2001

Remnant-like particle (RLP) cholesterol is an independent cardiovascular disease risk factor in women: results from the Framingham Heart Study.

Remnants of triglyceride-rich lipoproteins (TRL) of both intestinal and liver origin are considered to be atherogenic, but separation of remnant lipoproteins from other TRL is difficult. An assay has been developed that allows immunoseparation of remnant-like particles (RLP) and measurement of cholesterol (RLP-C) and triglyceride (RLP-TG). We measured RLP-C and RLP-TG in fast plasma samples obtained from 1567 women participating in cycle 4 of the Framingham heart study (FHS). When values from 83 women with cardiovascular disease (CVD) were compared with the values from 1484 women without disease, concentrations in women with CVD were found to be significantly higher for both RLP-C (0.215+/-0.102 vs. 0.186+/-0.162 mmol/l; +15.6%; P<0.0001) and RLP-TG (0.319+/-0.352 vs. 0.251+/-0. 716 mmol/l; +27.0%; P<0.0002). Logistic regression analysis revealed that RLP-C was significantly associated with prevalent CVD in women (P<0.002) after adjustment with other major risk factors. In conclusion, we have documented that RLP-C is an independent risk factor for CVD in women, and provides significantly more information than do triglycerides.

Adult↗
PubMed2001

Human triglyceride-rich lipoprotein apo E kinetics and its relationship to LDL apo B-100 metabolism.

Apolipoprotein (apo) E is a multifunctional protein that can act as a ligand for lipoprotein receptors. The receptor-mediated clearance of the triglyceride-rich lipoproteins (TRL) chylomicrons and VLDL from plasma is, in part, dependent on apo E. Enrichment of VLDL with apo E is thought to enhance receptor-mediated clearance of VLDL resulting in a low rate of conversion of VLDL to LDL. However, the kinetic mechanism controlling the concentration of apo E in VLDL is not known. We conducted kinetic studies on apo E in the TRL fraction (d < 1.006 g/ml) and apo B-100 in the TRL and LDL (d = 1.019-1.063 g/ml) fractions to assess the kinetic determinants of apo E concentration in TRL and to determine the effects that TRL apo E production and clearance rates have on the production rate of LDL apo B-100. Nineteen males between the ages of 24 and 73 underwent a primed-constant infusion with deuterated leucine tracer in the constantly-fed state. Apo B-100 from TRL and LDL, and apo E from TRL were isolated and their tracer incorporation measured by gas chromatography/mass spectrometry. The residence time and production rates of each protein were determined from the kinetic data using the SAAM II modeling program. The residence time and production rate of TRL apo E were about one-half that of TRL apo B-100 (1.8 +/- 1.0 vs. 2.9 +/- 2.1 h and 14.5 +/- 11.0 vs. 27.6 +/- 17.3 mg/kg per day, respectively). The production rate of TRL apo E was weakly correlated with the production rate of TRL apo B-100 (r = 0.424, P = 0.07). Multiple regression analysis showed that the residence time of TRL apo B-100 and the relative TRL apo E production rate (relative to the TRL apo B100 production rate) were negatively associated with LDL apo B-100 production rate, accounting for 68% of its variability. We conclude that (1) the concentration of apo E in TRL is highly correlated to its production rate, suggesting that production rate regulates the TRL apo E concentration, and (2) individuals with a relatively short TRL apo B-100 residence time and those producing TRL with a relatively low apo E content have the highest LDL apo B-100 production rates.

Adult↗
PubMed2001

Comparative study of HMG-CoA reductase inhibitors on fibrinogen.

Statins have a variable response on fibrinogen, and these changes may have implications on cardiovascular events. In this randomized placebo-controlled crossover study, we evaluated whether changes in fibrinogen levels were different between atorvastatin and other statin-treated patients. Adult coronary heart disease (CHD) patients aged 39-83 years with LDL cholesterol levels > or = 130 mg/dl were randomized to atorvastatin 80 mg (n = 84) and one of the following statins: fluvastatin 80 mg (n = 23), lovastatin 80 mg (n = 20), pravastatin 40 mg (n = 22) or simvastatin 40 mg (n = 20) each for 12 weeks in either order. Fibrinogen was analyzed by an automated method of Clauss. Three independently acquired samples were obtained within 1 min of tourniquet application, and each specimen was measured in duplicate. Statistical analyses were performed using a mixed model repeated measures analysis of variance procedure with SAS version 6.12. There were no significant changes in fibrinogen between treatment groups. This study evaluated changes in fibrinogen with established pre-analytical and analytical procedures known to minimize variability in fibrinogen measurement, and we did not observe any differences in fibrinogen levels in the treatment groups.

Adult↗
PubMed2001

Subpopulations of high density lipoproteins in homozygous and heterozygous Tangier disease.

Tangier disease (TD) is characterized by severe high-density lipoproteins (HDL) deficiency, hypercatabolism of HDL constituents, impaired cellular cholesterol efflux, and mutations in the gene of ATP-binding cassette 1 (ABC-1). In the present study, we determined plasma lipid and apolipoprotein levels, and HDL subpopulations, in 110 subjects from a large TD kindred in which the proband was homozygous for an A-->C missense mutation at nucleotide 5338 of the ABC-1 transcript. In the proband HDL-C, apoA-I, and apoA-II concentrations were 2, 1, and 2 mg/dl, respectively, apoA-I was present only in prebeta(1), while apoA-II was found free of apoA-I in two distinct alpha mobility subpopulations with different sizes. The smaller size particles contained only apoA-II while the larger one contained apoA-II and apo(a). Relative to unaffected male relatives (n=30), male heterozygotes (n=21) had significant reductions (P<0.001) in plasma HDL-C (-45%), apoA-I (-34%), apoA-II (-59%), apoA-IV (-40%), Lp(a) (-62%), and apoB (-55%) concentrations, and a significant increase (P<0.05, +33%) in plasma apoC-III levels. Female heterozygotes (n=11) similarly had significant reductions (P<0.001) in the concentrations of plasma HDL-C (-42%), apoA-I (-27%), apoA-II (-52%), Lp(a) (-27%), and (P<0.01) apoA-IV (-28%), apoB (-13%), and a significant increase (P<0.05) in plasma apoE levels (+29%) as compared to unaffected female relatives (n=41). Large size HDL subpopulations, especially the two LpA-I particles: alpha(1) and prealpha(1) were dramatically reduced in both male and female heterozygotes relative to their unaffected family members. Since apoA-II decreased more than apoA-I in both male and female heterozygotes, the ratios of apoA-I/apoA-II were significantly (P<0.01) increased. The prevalence of CHD was 60% higher in the 32 heterozygotes than in the 71 unaffected relatives even though the latter group was on average 7 years older. We conclude that TD homozygotes have only prebeta(1) apoA-I-containing HDL subpopulations, while heterozygotes have HDL that is selectively depleted in the large alpha(1), prealpha(1), and alpha(2), prealpha(2) subpopulations, resulting in HDL particles that are small in size, poor in cholesterol, but relatively enriched in apoA-I compared to those of their unaffected relatives. These abnormalities appear to result in a higher risk of CHD in heterozygotes than in unaffected controls.

Adult↗
PubMed2001

Human apolipoprotein A-IV metabolism within triglyceride-rich lipoproteins and plasma.

In order to investigate the metabolism of apo A-IV within TRL and plasma, we assessed TRL and plasma apo A-IV kinetics in 19 and 4 subjects, respectively, consuming an average US diet for a 6-week period. At the end of this diet study, each subject received a primed-constant infusion of deuterated leucine over a 15 h time period with hourly feeding, and blood samples were drawn at 10 time points. TRL was separated by ultracentrifugation. Apo A-IV was isolated by immunoprecipitation and/or SDS-PAGE. Apo A-IV concentrations were determined by immunoelectrophoresis. Stable isotope tracer/tracee ratios were measured by gas chromatography/mass spectrometry, and the data were analyzed by multicompartmental modeling. The mean concentrations of plasma and TRL apo A-IV during the isotope infusion period were 21.0+/-3.2 and 0.66+/-0.25 mg/dl, respectively, and these values were 11.5 and 30.5% higher than those of fasting samples. The mean TRL and plasma apo A-IV residence times (RT) were 1.97+/-0.57 and 2.71+/-0.65 days, and transport rates (TR) were 0.17+/-0.19 and 3.90+/-1.24 mg/kg per day, respectively. There were significant correlations between TRL apo A-IV concentrations and TR (r(2)=0.79, P<0.001), and between TRL apo A-IV pool size and TRL cholesterol levels (r(2)=0.29, P=0.02). Our data indicated that; (1) TRL apo A-IV has a RT of 1.97 days which is similar to that earlier reported for HDL apo A-IV; (2) Apo A-IV recirculates between TRL and other slowly turning over pools; (3) the primary determinant of TRL apo A-IV levels is its TR; and (4) there is no correlation between TRL apo A-IV and apo B48 fractional catabolism in TRL.

Adult↗
PubMed2001

Association of the Sst-I polymorphism at the APOC3 gene locus with variations in lipid levels, lipoprotein subclass profiles and coronary heart disease risk: the Framingham offspring study.

Apolipoprotein (apo) CIII participates in the regulation of the metabolism of triglyceride-rich lipoproteins and it is a major component of chylomicrons and VLDL. The APOC3 gene is on chromosome 11q23 and is highly polymorphic. The less common allele (S2) of the SstI polymorphism on the 3' untranslated region of the APOC3 gene has been previously associated with increased triglycerides, total cholesterol (TC), and apoCIII levels and cardiovascular risk on several, but not all, studies. The aim of this study was to examine the association of this polymorphism with plasma lipid levels, lipoprotein subfractions and coronary heart disease (CHD) risk in a population-based study: The Framingham Offspring Study. The frequency of the S2 allele was 0.086, consistent with previous reports in Caucasian populations. In men, the S2 allele was associated with lower concentrations of high-density lipoprotein cholesterol (HDL-C; P<0.04) and HDL2-C (P<0.02) and a significant increase in apoCIII non-HDL (P<0.05). TG levels were higher in men carriers of the S2 allele, but this association did not reach statistical significance (P=0.30). Conversely, in women, the S2 allele was associated with increased TC (P<0.03), low-density lipoprotein cholesterol (LDL-C; P<0.03), and ApoB levels (P<0.04). Lipoproteins subfractions were also examined using nuclear magnetic resonance (NMR) spectroscopy. S2 male carriers had significantly lower concentrations of large LDL and a significant reduction in LDL particle size (P<0.04). In women, there was a significant increase in intermediate LDL particles (P<0.05) with no significant effect on lipoprotein diameters. We also examined the associations between the S2 allele and biochemical markers of glucose metabolism. In men, the S2 allele was associated with elevated fasting insulin concentrations (P<0.04), whereas no significant associations were observed in women. Despite the described associations with lipid and glucose metabolism related risk factors, we did not find any significant increase in CHD risk associated with the S2 allele in this population.

Alleles↗
PubMed2001

Apolipoprotein E genotype affects plasma lipid response to atorvastatin in a gender specific manner.

The response to therapy with hypolipidemic agents shows considerable individual variation. These differences may be due to the interaction of environmental and genetic factors that affect drug bioavailability, receptor function or ligand structure. Our objective was to assess the effect of apolipoprotein (apo) E genotype and gender on lipid-lowering response to the HMG CoA reductase inhibitor, atorvastatin. Genotyping was carried out on DNA from 328 male and female subjects who participated in a multicentric, double-blind clinical trial, and received 10 mg/day of atorvastatin. Our data demonstrate no significant gender differences for LDL cholesterol levels at baseline. Moreover, mean LDL-C lowering was similar in men (-36.2%, range -2.7 to -57.8%) and in women (-38.1%, range -9.5 to -58.5%) as compared to baseline. However, men carrying the epsilon2 allele had a significantly higher mean LDL-C response (-44%) than epsilon3 homozygotes (-37%) and epsilon4 carriers (-34%); P=0.01 for apoE group by treatment interaction. No such gene/treatment interactions were noted in women, with those carrying the epsilon2 allele showing a similar mean response (-34%) as epsilon3 homozygotes (-39%) and epsilon4 carriers (-34%). Mean plasma triglyceride lowering with atorvastatin was 17%. A significant apoE group by treatment interaction (P=0.010) was also observed in men, with epsilon2 carriers being more responsive (-27%) than epsilon3/3 (-13%) and epsilon4 (-22%). This interaction was not observed in women. In summary, atorvastatin treatment had similar effects on plasma lipid levels in both men and women; however, the apoE gene locus was a significant predictor of LDL-C and TG responses to atorvastatin therapy in men, but not in women.

Anticholesteremic Agents↗
PubMed2001

Association of the A/T54 polymorphism in the intestinal fatty acid binding protein with variations in plasma lipids in the Framingham Offspring Study.

We investigated the potential role of the genetic variation at the intestinal fatty acid binding protein gene (FABP2) in influencing lipid levels in a representative sample of the Framingham Offspring Study participants (n=1930). In men, the T54 allele was associated with significantly higher LDL-cholesterol (3.47+/-0.83 vs. 3.36+/-0.83 mmol/l; P<0.047), and ApoB (1.04+/-0.23 vs. 1.01+/-0.24 g/l; P<0.020) after adjustment for familial relationship, age, BMI, smoking, alcohol intake and the use of beta-blockers compared with the A54 allele. This relationship with ApoB continued to be significant after adjustment for APOE genotype (P<0.034). In women, the T54 allele was associated with significantly higher total-cholesterol (5.32+/-1.01 vs. 5.17+/-0.98 mmol/l; P<0.049) and LDL-cholesterol (3.31+/-0.93 vs. 3.18+/-0.85 mmol/l; P<0.023) after adjustment for covariates and menopausal status, estrogen therapy and APOE genotype. In men, the T54 allele was associated with significantly higher levels of small VLDL and lower levels of large HDL. Moreover, there was no significant relationship between FABP2 alleles and lipoprotein diameter or the prevalence of coronary heart disease in both genders. Our data are consistent with the T54 IFABP increasing the flux of lipids through the enterocyte leading to an increase in chylomicron secretion.

Age Distribution↗