Effects of apolipoprotein E genotypes and other risk factors on the development of coronary artery disease in Southern Turkey

BACKGROUND: Apolipoprotein E (apoE) plays a major role in lipoprotein metabolism and lipid transport. Associations between apoE genotypes, coronary artery disease (CAD) and other risk factors have been described by many investigators. The aim of this study was to investigate the role of apoE gene polymorphism and other risk factors in the development of CAD in subjects whose coronary arteries were evaluated by means of coronary angiography. METHODS: The study population consisted of 199 subjects (114 male and 55 female). Of the total, 107 had CAD. The apoE gene was amplified by polymerase chain reaction (PCR) and then digested by CfoI restriction enzyme. The plasma lipid levels and other risk factors were also determined in all subjects. RESULTS: The epsilon2 and epsilon4 allele frequencies and genotypes carrying epsilon4 allele were significantly higher in CAD (+) patients. Plasma lipids except triglycerides were increased in CAD (+) cases. We found that apoE genotypes, HT, DM, male gender, age and smoking were the independent predictors of CAD. There was no association between apoE alleles and lipids. CONCLUSION: We conclude that apoE polymorphism (presence of epsilon4 allele) is associated with the development of CAD in Southern Turkey. In our study, we did not observe any effect of apoE alleles on lipid levels.     

Apolipoprotein E phenotypes, serum lipoproteins and apolipoproteins in angiographically assessed coronary heart disease

To determine the influence of the apolipoprotein E polymorphism on the occurrence of coronary artery disease (CAD) and on serum lipids, lipoproteins and apolipoproteins we studied 145 patients with angiographically defined CAD and compared them with 153 control subjects without history or complaints of vascular disease and with 35 subjects without significant stenosis on coronary arteriography. Subjects with hypertension, diabetes mellitus and endocrine or metabolic disorders were excluded. Covariance analysis and logistic regression analysis were performed with adjustment for age, sex, smoking habits and relative body weight. There were no significant differences for the apoE phenotypes on risk of cardiovascular disease. The CAD group had significantly higher mean values of serum cholesterol and triglycerides, very-low-density lipoprotein (VLDL)-cholesterol and VLDL-triglycerides, low-density lipoprotein (LDL)-cholesterol and apoprotein B; they had lower high-density lipoprotein (HDL)-cholesterol and apo A-I. The combination of LDL-cholesterol, apoA-I and VLDL-cholesterol was the best model in predicting cardiovascular disease. ApoE phenotype group E3/E2 had significantly lower values for serum cholesterol, LDL-cholesterol, and apoB and higher levels of apoE in comparison with the phenotype groups E3/E3 and E4/E3. The combination of LDL-cholesterol, cholesterol, apoE and VLDL-triglycerides was the best model in predicting the apoE phenotype. Thus, taking other risk factors into account, the apoE phenotype is not an independent risk factor for CAD; the apoE polymorphism influences lipoprotein levels and possibly, in that way, indirectly also the risk for CAD.     

Improvement of myocardial blood flow by lipid-lowering therapy with pravastatin is modulated by apolipoprotein E genotype

OBJECTIVE: Apolipoprotein E (apoE) polymorphism affects the risk of advanced coronary artery disease, but its role in early atherosclerosis remains unknown. We used positron emission tomography (PET) to study whether coronary reactivity or its response to pravastatin is related to the apoE genotype. MATERIAL AND METHODS: Samples from 44 mildly hypercholesterolaemic men (aged 35 +/- 4 years) of an earlier trial were re-analysed according to apoE genotype. Subjects were randomized to receive either 40 mg/day pravastatin or placebo for 6 months. To assess coronary reactivity, myocardial blood flow was measured by PET at rest and during adenosine infusion. PET studies and lipid analyses were done at baseline and after 6 months of therapy. RESULTS: There were no differences between apoE epsilon3/3 and epsilon4/3 genotypes in basal or adenosine-stimulated flow or in coronary flow reserve (CFR) at baseline. There was a significant apoE genotype-by-treatment group interaction regarding the change in adenosine-stimulated flow (ANCOVA; p = 0.018) and CFR (p = 0.020) at the end of the study. In the pravastatin group, the adenosine-stimulated flow increased by 32.5 % in subjects with epsilon3/3 (n = 9), but decreased non-significantly (-14.4 %) in subjects with epsilon4/3 (n = 9) (p = 0.0009). The corresponding changes in CFR were +17.8 % for epsilon3/3 and (-11.9 % for epsilon4/3 (p = 0.05). There were no significant changes from the baseline values in placebo recipients. After pravastatin treatment, both genotype groups showed a similar decrease in serum total and low-density lipoprotein cholesterol (p<0.0001 for both). CONCLUSIONS: Coronary function improves by 6 months of pravastatin in subjects with the apoE epsilon3/3 genotype, but not in those with the epsilon4/3.     

Effect of apolipoprotein E (apoE) phenotype on the apoE content of CSF-HDL in children

BACKGROUND: The majority of the lipoprotein in cerebrospinal fluid (CSF) is apolipoprotein E (apoE)-containing HDL. Since neuronal cells express lipoprotein receptors which recognize apoE, apoE in CSF-HDL is believed to be important for the development of central nervous system (CNS) in children. In adults, the apoE phenotype affects the plasma apoE concentration and the epsilon 4 allele is a risk factor for Alzheimer's disease. Due to the requirement for CNS development, we examined whether the apoE phenotype affects the composition and concentration of CSF-HDL in children. METHODS: We determined the apoE phenotype in 107 neurologically normal subjects, including 67 children (<20 years), by isoelectronic focusing. We also measured apoE, total cholesterol (TC), and phospholipid (PL) concentrations in the CSF. RESULTS: The respective frequencies of apoE4/3, E3/3 and E3/2 were 16.4%, 77.6%, and 6.0%. The allele frequencies of epsilon 4, epsilon 3, and epsilon 2 were 0.082, 0.888, and 0.030, respectively. There were no significant differences in the CSF-apoE, TC, or PL concentrations or the apoE/PL ratio among the apoE phenotypes. However, the CSF-apoE/PL ratio was significantly higher in children than in adults. CONCLUSION: The apoE phenotype does not affect the composition or concentration of CSF-HDL in children. We speculate that an apoE4 carrier is prevented in childhood from the impaired development of central nervous system by CSF-HDL enriched with apoE.     

Influence of apolipoprotein E polymorphism on serum lipid and lipoprotein changes: a 21-year follow-up study from childhood to adulthood. The Cardiovascular Risk in Young Finns Study.

BACKGROUND: We examined the influence of apolipoprotein E (apoE) polymorphism on longitudinal changes in serum lipids by following the subjects participating in The Cardiovascular Risk in Young Finns Study over a 21-year period. METHODS: Serum lipids were determined in randomly selected Finnish children and adolescents in 1980 and the subjects were re-examined in 1983, 1986 and after 21 years in 2001. ApoE polymorphism was determined in 1736 participants, and serum lipid values and apoE phenotypes were available for 1233 subjects. RESULTS: ApoE phenotype-related differences in serum total and low-density lipoprotein (LDL)-cholesterol were maintained throughout the 21-year follow-up from childhood to adulthood, i.e., the apoE epsilon2 allele was consistently associated with lower and the epsilon4 allele with higher total and LDL-cholesterol (p<0.001 for all). In adulthood, there was also a significant apoE phenotype-related difference in high-density lipoprotein (HDL)-cholesterol (p=0.007), and the epsilon2 allele was associated with higher and the epsilon4 allele with lower apoA-I and HDL-cholesterol. In addition, apoB increased in the phenotype order E3/2相似文献   

Effect of hepatic lipase -514C->T polymorphism and its interactions with apolipoprotein C3 -482C->T and apolipoprotein E exon 4 polymorphisms on the risk of nephropathy in chinese type 2 diabetic patients

OBJECTIVE: Triglyceride-rich lipoprotein particles may promote the progression of diabetic nephropathy. Patients with diabetic nephropathy have increased plasma triglycerides and reduced activity of hepatic lipase (HL), which hydrolyzes triglycerides. We hypothesized that the HL -514C-->T polymorphism, which reduces HL expression, and its interactions with polymorphisms in apolipoprotein (apo) E and apoC3 increase the risk of diabetic nephropathy. RESEARCH DESIGN AND METHODS: In a case-control study involving 374 Chinese type 2 diabetic patients with and 392 without diabetic nephropathy, we genotyped the HL -514C-->T, apoE exon 4, and apoC3 -482C-->T polymorphisms. RESULTS: HL -514T-containing genotypes (T+) were associated with diabetic nephropathy (OR = 1.7, P = 0.0009). Adjustment by multiple logistic regression for hypertension, triglycerides, sex, non-HDL cholesterol, BMI, smoking, and alcohol intake did not diminish the association (OR = 1.8, P = 0.003). The association between HL T+ genotypes and diabetic nephropathy appeared stronger in diabetic patients with apoC3 -482 non-TT genotypes (OR = 1.9, P = 0.003) or apoE epsilon2 or epsilon4 alleles (OR = 2.2, P = 0.005). Subjects with HL TT exhibited trends toward increased triglyceride and non-HDL cholesterol levels compared with CC carriers. CONCLUSIONS: HL T+ genotypes might increase the risk of developing diabetic nephropathy by slowing clearance of triglyceride-rich remnant lipoproteins. In concert with other risk factors (e.g., hyperglycemia), lipid abnormalities may damage the kidneys and endothelium, where reduced binding sites for lipases may precipitate a vicious cycle of dyslipidemia, proteinuria, and nephropathy.     

APOE genotypes and dyslipidemias in a sample of the Portuguese population.

The objective of this work was to study the distribution of apolipoprotein E (APOE) genotypes in a sample of the Portuguese population, and its association with the dyslipidemias observed. Study participants were healthy users of local Public Health Laboratories in six regions of mainland Portugal (Porto, Vila Real, Viseu, Lisboa, Portalegre and Faro). A total of 779 men and 1153 women aged 15-74 years agreed to participate. Fasting lipid levels and APOE genotypes were determined centrally at the National Institute of Health in Lisboa. The frequency distribution of APOE alleles was: epsilon2=5.3%, epsilon3=84.9% and epsilon4=9.8%. Dyslipidemias were present in 66.6% of men and 60.7% of women. Comparison of APOE genotypes and relative allele frequencies showed that in dyslipidemic compared to normolipidemic subjects, the epsilon4 allele was more frequent in both sexes, although in a more pronounced way in men than in women due to higher frequencies of epsilon3/epsilon4 and epsilon4/epsilon4 genotypes. The known association of the epsilon4 allele with high cholesterol levels, the association of the epsilon2 allele with low cholesterol levels, and the association of the epsilon2 allele with high levels of triglycerides and low levels of high-density lipoprotein-cholesterol were confirmed in this study.     

Regional differences in apolipoprotein E polymorphism in Finland

Apolipoprotein E (apoE) polymorphism is a genetic determinant of plasma lipid levels and of coronary heart disease risk. We determined apoE phenotypes and plasma lipid levels in 1564 subjects aged three to 18 years, living in five geographical areas of Finland in 1980. ApoE phenotyping was performed directly from plasma by isoelectric focusing and immunoblotting. The serum concentrations of total cholesterol, low density lipoprotein cholesterol and apolipoprotein B varied with apoE phenotype, and there were increases in all three variables (all P less than 0.001) of the order of E2/2 less than E3/2 less than E4/2 less than E3/3 less than E4/3 less than E4/4. These differences were present in all five areas. The mean levels of high density lipoprotein cholesterol, apolipoprotein A-I and triglyceride in the subjects did not differ between the apoE phenotypes or between their areas of residence. The apoE phenotype dependency of serum total and LDL cholesterol remained significant in all five areas during the six year follow-up from 1980 to 1986, when the mean level of serum total cholesterol fell by 5.8% in east (P less than 0.05) and by 4.4% in west Finland (P less than 0.05); the fall was steeper (P less than 0.01) in the east than the west. In all subjects, particularly those in west Finland, the size of the falls of serum total and LDL cholesterol concentrations depended on the apoE phenotype in the order of E3/2 less than E3/3 less than E4/3, but this effect was not seen in the east.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum zinc, copper, insulin and lipids in Alzheimer''s disease epsilon 4 apolipoprotein E allele carriers*

BACKGROUND: Copper (Cu) and zinc (Zn) have been implicated in the development of Alzheimer's disease (AD) and, in this regard, Cu and Zn serum concentrations have been analysed but with inconclusive results. Serum insulin, glucose and cholesterol concentrations have been related to the apolipoprotein E genotype in non-AD populations. DESIGN: In this study, we have analysed the relationship between serum Cu, Zn, insulin, glucose and lipid parameters (cholesterol, triglycerides, apoA and apoB apolipoproteins) in AD and AD epsilon 4 apolipoprotein E carriers by multivariate analysis using logistic regression, including the variables that showed a significance of P < 0.05 in the bivariate analysis. RESULTS: The results obtained show that epsilon 4 apoE allele is an independent AD risk factor (OR = 6. 67, 95% CI = 2.59-17.16). In AD epsilon 4 apoE allele carriers, we found significantly higher Zn, Cu and insulin serum concentrations. Non-demented control subjects with at least one epsilon 4 apoE allele had the lowest serum insulin concentrations. There was no significant association between epsilon 4 apolipoprotein E allele and lipid parameters in the sample studied. CONCLUSIONS: In AD we have found a significant association between higher serum Zn, Cu and insulin concentrations and the presence of an epsilon 4 apoE allele, but only greater serum Zn concentration appears to be an independent risk factor associated with the development of AD.     

Gender-related effect of apo E polymorphism on lipoprotein particle sizes in the middle-aged subjects

OBJECTIVES: We determined the frequencies of apolipoprotein E (apo E) alleles and examined the effect of apo E polymorphism on lipoprotein particle sizes in Serbian healthy, middle-aged individuals. DESIGN AND METHODS: We performed apo E phenotype by immunobloting method in 183 men and 143 women (mean years: 56.3+/-10.60 and 54.9+/-10.31, respectively). Plasma lipid and apolipoprotein levels were measured by routine laboratory methods. LDL and HDL particle sizes were determined by nondenaturing polyacrylamide gradient (3-31%) gel electrophoresis. RESULTS: The apo E allele frequencies were epsilon2--4.9%, epsilon3--86.5%, and epsilon4--8.6%. Men with epsilon4 allele had lower HDL-C and Apo AI concentrations than epsilon3 men. The epsilon2 allele men had the smallest LDL particles, highest percent of subjects with LDL phenotype B and highest TG/HDL-C ratio. Women with epsilon2 allele had lowest concentration of apo B. The epsilon4 allele women had smallest HDL particles and highest percent of the subjects with small-sized HDL phenotype. CONCLUSIONS: This study showed gender-related effect of apo E polymorphism on lipoprotein particle size. In men, possession of the epsilon2 allele is associated with small LDL particles, whereas in women, epsilon4 allele is associated with small HDL particles. Differences in gender-related influence of apo E polymorphism on LDL and HDL particle sizes could be clinically useful in strategy for reduction of coronary disease risk in middle-aged men and women.     

Phenotype-dependent differences in apolipoprotein E metabolism and in cholesterol homeostasis in human monocyte-derived macrophages.

In this study, we investigated the impact of the common apoE polymorphism on apoE metabolism and cholesterol homeostasis in monocyte-derived macrophages isolated from E2/2, E3/3, and E4/4 subjects. Unloaded cells of all genotypes contained similar amounts of free cholesterol, cholesteryl ester, and apoE mRNA. E3/3 cells secreted 77 and 30% more apoE than E2/2 or E4/4 cells, respectively. Pulse-chase studies confirmed that the apoE secretion rate was greatest in E3/3 and least in E2/2 cells and showed that a portion of apoE2, but not apoE3 or apoE4, was degraded intracellularly. Surface binding of apoE was greatest in E4/4 cells, as revealed by heparinase treatment. On cholesterol loading with acetylated LDL, apoE mRNA levels and protein secretion rose most in E4/4 and least in E2/2 cells. Cholesterol and cholesteryl ester content, however, rose most in E2/2 and least in E3/3 cells. Incubations with 3H-cholesterol-labeled acetylated LDL revealed that E2/2 cells were most efficient at secreting cholesterol. The greatest reuptake of 3H-cholesterol-rich particles was from E4/4 macrophage- conditioned media. Thus, E2/2 macrophages, despite a low apoE secretion rate, are protected from cholesterol storage by apoE-mediated cholesterol efflux. In E3/3 macrophages, cholesterol accumulation is lessened by a high basal apoE secretion rate. E4/4 macrophages secrete the most apoE but lack effective net cholesterol efflux due to enhanced surface binding and reuptake of cholesterol-rich particles.     

北京地区晚发性阿尔兹海默病患者apo E基因多态性与血脂的相关性

目的探讨晚发型阿尔兹海默病(LOAD)患者载脂蛋白E(apo E)基因多态性与血脂水平之间的关系。方法采用基因芯片法检测150例LOAD患者(LOAD组)及150名体检健康者(正常对照组)apo E基因多态性,同时检测总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、小而密低密度脂蛋白胆固醇(sd-LDL-C)、高密度脂蛋白胆固醇(HDL-C)、载脂蛋白B(apo B)、脂蛋白(a)[Lp(a)]水平。采用多因素非条件Logistic回归分析筛选LOAD的相关危险因素。结果LOAD组E2/3和E3/3基因型频率均低于正常对照组(P<0.05),E3/4和E2/4基因型频率均高于正常对照组(P<0.01)。LOAD组ε3等位基因频率低于正常对照组(P<0.05),ε4等位基因频率高于正常对照组(P<0.01)。与正常对照组比较,LOAD组TC、LDL-C和sd-LDL-C水平明显升高(P<0.01),HDL-C水平明显降低(P<0.01),其他血脂项目差异均无统计学意义(P>0.05)。TC及LDL-C水平在LOAD组ε2、ε3和ε4表型患者中依次升高(P<0.05)。正常对照组ε4表型LDL-C水平明显高于ε2表型(P<0.05)。apo Eε4等位基因和LDL-C升高是LOAD发生的危险因素[比值比(OR)值分别为14.454、5.824,95%可信区间(CI)分别为5.793~16.368、2.582~7.973],HDL-C升高则是LOAD的保护因素(OR=0.020,95%CI为0.006~0.352)。结论apo E基因多态性与脂质代谢密切相关,ε4等位基因可能是LOAD发病的重要遗传因素之一。     

Comparative in vivo metabolism of apolipoproteins E2 and E4 in heterozygous apoE2/4 subjects

Apolipoprotein E (apoE) exists in three common forms in humans: the wild-type apoE3 and two common genetic variants, apoE2 and apoE4. Although previous studies have examined the metabolism of the different apoE isoforms in human subjects, they have not involved direct comparison of two different isoforms in subjects heterozygous for the same two isoforms. We conducted this study to directly compare the catabolism of apoE2 and apoE4 in heterozygous E2/4 subjects in vivo. Iodine 131-labeled apoE2 and iodine 125-labeled apoE4 were simultaneously injected into three E4/2 heterozygous subjects. The mean residence time of apoE4 (0.40 +/- 0.01 day) was found to be one-third that of apoE2 (1.20 +/- 0.18 day). ApoE2 was present primarily in high-density lipoprotein, whereas apoE4 was present equally in very low density and high-density lipoprotein. In all lipoprotein subfractions, apoE4 was catabolized at a much faster rate than apoE2. In conclusion, E4 is catabolized three times faster than apoE2 in heterozygous E2/4 subjects, indicating that these two apoE isoproteins have distinct metabolic pathways.     

The effect of the APOE polymorphism on HDL-C concentrations depends on the cholesterol ester transfer protein gene variation in a Southern European population

BACKGROUND: Apolipoprotein E (ApoE) locus has consistently shown a significant association with low-density lipoprotein cholesterol (LDL-C). However, its impact on high-density lipoprotein cholesterol (HDL-C) has been highly controversial suggesting that it may be context-dependent. We examined the gene-gene interaction between the common ApoE and the CETP polymorphisms in determining HDL-C concentrations in men and women from the general population. METHODS: 550 unrelated Caucasian subjects were randomly selected from a Mediterranean Region in Spain. Plasma lipids, anthropometric, clinical and lifestyle variables were measured. Common ApoE and CETP-TaqIB polymorphisms were determined. RESULTS: We have found a gene-gene interaction between and ApoE and the CETP loci in determining HDL-C concentrations. Thus, after adjustment for gender, age, body mass index, tobacco smoking, alcohol consumption, physical exercise and medication, carriers of the E4 allele had lower HDL-C concentrations [mean and (standard error): 40.1 (2.6) mg/dL] than E2 subjects [47.7 (3.2) mg/dL; p=0.019], and even lower than those of the E3 subjects [44.7 (1.4) mg/dL; p=0.042], only if they had the B1B1 genotype. However, mean HDL-C concentrations were higher among those with E4 allele carrying the B2 allele at the CETP gene locus [50.5 (2.3) mg/dL], and lower among E2 subjects carrying the B2 allele [45.5 (2.6) mg/dL]. This interaction was observed in both men and women. This gene-gene interaction remained statistically significant even after additional adjustment for triglycerides. CONCLUSIONS: The effect of the ApoE polymorphism on HDL-C concentrations depends on the CETP polymorphism, explaining some of the controversial results previously reported for this polymorphism.     

Liver-directed gene transfer and prolonged expression of three major human ApoE isoforms in ApoE-deficient mice.

Apolipoprotein E (apoE) plays a key role in lipoprotein metabolism and may have other important biological functions. In humans, there are three common, naturally occurring isoforms of apoE that are associated with differences in lipid levels and atherosclerosis. However, the direct in vivo effects of the apoE isoforms on lipoprotein metabolism and atherosclerosis are not yet fully understood. To investigate the effect of the apoE isoforms in vivo, we constructed second-generation recombinant adenoviruses encoding each of the apoE isoforms. These recombinant adenoviruses were injected intravenously into apoE-deficient mice fed a Western diet (mean baseline cholesterol level 1401 mg/dl) in order to study their effects in the absence of endogenous mouse apoE. Hepatic expression of apoE3 and apoE4 completely normalized the lipoprotein profile; 3 d after injection, mean plasma cholesterol levels were 194 and 217 mg/ dl, respectively, and this effect was maintained for at least 6 wk. Expression of apoE2 had much less effect on lipoprotein levels (mean cholesterol level 752 mg/dl 3 d after injection), despite much higher plasma levels of apoE2 compared with apoE3 and apoE4; by 6 wk after injection the cholesterol levels had returned to baseline levels in the apoE2-expressing mice. Expression of all three isoforms significantly increased HDL cholesterol levels by approximately threefold and was independent of the cholesterol-lowering effect. ApoE transgene expression was substantially prolonged compared with that achieved using a first generation adenovirus and apoE was readily detected in plasma 3 mo after virus injection. These studies demonstrate: (a) prolonged in vivo expression of human apoE isoforms in apoE deficient mice after second-generation recombinant adenovirus-mediated somatic gene transfer; and (b) significantly impaired ability of apoE2 in vivo to mediate clearance of remnant lipoproteins in apoE-deficient mice fed a Western diet compared with apoE3 and apoE4.     

Effect of apolipoprotein E4 allele on plasma LDL cholesterol response to diet therapy in type 2 diabetic patients

OBJECTIVE: The aim of this study was to investigate the effect of apolipoprotein (apo)E4 allele on plasma LDL cholesterol response to calorie-restricted diet therapy in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: Twenty-four diabetic patients with the apoE3/3 genotype and 11 diabetic patients with the apoE4/3 genotype were recruited. Participants were hospitalized for calorie-restricted diet therapy (25.0 kcal. kg body wt(-1). day(-1)) for 14 days. Body weight, fasting plasma glucose (FPG) levels, and plasma lipid levels on hospital days 1 and 14 were compared between the two apoE genotype groups. RESULTS: There were no significant differences in baseline FPG levels, HbA(1c) levels, BMI, and plasma levels of total cholesterol, triglyceride, and HDL cholesterol between the two apoE genotype groups, but baseline plasma levels of LDL cholesterol were significantly higher in the apoE4/3 group than in the apoE3/3 group. Body weight decreased slightly and FPG levels decreased significantly after diet therapy in both apoE genotype groups. In the apoE3/3 group, only plasma levels of triglyceride decreased significantly after diet therapy, whereas in the apoE4/3 group, plasma levels of triglyceride, total cholesterol, and LDL cholesterol decreased significantly after diet therapy. The decrease (percentage of change) in total cholesterol (-16.3 vs. -6.6%) and LDL cholesterol (-15.6 vs. -0.7%) after diet therapy was significantly greater in the apoE4/3 group than in the apoE3/3 group. CONCLUSIONS: Calorie-restricted diet therapy is more effective in reducing plasma LDL cholesterol in type 2 diabetic patients with the apoE4 allele.     

The effects of extended-release niacin on carotid intimal media thickness, endothelial function and inflammatory markers in patients with the metabolic syndrome

BACKGROUND: Niacin is an agent that significantly increases high-density lipoprotein cholesterol (HDL-C), but its effects on surrogate markers of atherosclerosis and inflammatory markers are less clear. We studied the effects of niacin on carotid intimal media thickness (IMT), brachial artery reactivity as well as markers of inflammation and the metabolic profile of patients with metabolic syndrome. METHODS AND RESULTS: Fifty patients with the metabolic syndrome (Adult Treatment Panel (ATP) III criteria) were randomised to either extended-release niacin (1000 mg/day) or placebo. After 52 weeks of treatment, there was a change of carotid IMT of +0.009 +/- 0.003 mm in the placebo group and -0.005 +/- 0.002 mm in the niacin group (p = 0.021 between groups). Endothelial function improved by 22% in the group treated with niacin (p < 0.001), whereas no significant changes were seen in the placebo group. High sensitivity C-reactive protein decreased by 20% in the group treated with niacin for 52 weeks (p = 0.013). Niacin increased HDL-C (p < 0.001) and decreased low-density lipoprotein cholesterol and triglycerides (p < 0.001) significantly, and there were no adverse effects on fasting glucose levels after 52 weeks of treatment. CONCLUSION: Extended-release niacin therapy effects a regression in carotid intimal medial thickness and improvement in metabolic parameters (increased HDL and reduced triglycerides). Furthermore, extended-release niacin may demonstrate an anti-atherogenic effect in the metabolic syndrome by improving endothelial function and decreasing vascular inflammation.     

Impact of bezafibrate and atorvastatin on lipoprotein subclass in patients with type III hyperlipoproteinemia: result from a crossover study

BackgroundWe elucidated the difference between the effects of bezafibrate and atorvastatin in hypertriglyceridemia with apoE2/2 and 3/3.MethodsAn open randomized crossover study consisted of a 4-week treatment period with bezafibrate (400 mg daily) or atorvastatin (10 mg daily) and a 4-week wash-out period.ResultsBezafibrate significantly decreased serum concentrations of triglyceride (apoE2/2, E3/3: ?49.2%, ?39.0%) and significantly increased high-density lipoprotein (HDL) cholesterol (+ 28.5%, + 26.1%) in both apoE phenotypes but did not change serum concentrations of low-density lipoprotein (LDL) cholesterol. Atorvastatin significantly decreased serum concentrations of LDL cholesterol (? 34.0%, ?30.0%) and triglyceride (? 27.6%, ?25.8%) in both apoE phenotypes but did not change HDL cholesterol concentrations. Changes in cholesterol in lipoprotein subfractions were not different between apoE2/2 and E3/3. Bezafibrate changed cholesterol distribution from small- to large-sized LDL and from large- to small-sized HDL. On the other hand, atorvastatin decreased cholesterol in all apoB-containing lipoprotein subfractions but did not change any of the HDL subfractions.ConclusionBezafibrate and atorvastatin improve atherogenic dyslipidemia in considerably different ways. Extrapolating from the present data, we presume that the combination of these drugs may contribute to reduce LDL-C/HDL-C ratio effectively as well as lowering concentrations of serum triglyceride.