CETP (cholesteryl ester transfer protein) promoter -1337 C>T polymorphism protects against coronary atherosclerosis in Japanese patients with heterozygous familial hypercholesterolaemia

CETP (cholesteryl ester transfer protein) and HL (hepatic lipase) play a role in the metabolism of plasma lipoproteins, but the effects of CETP and LIPC (gene encoding HL) genotypes on coronary atherosclerosis may be dependent on LDL (low-density lipoprotein)-receptor activity. Recently, the -1337 C>T polymorphism in the CETP gene has been reported in REGRESS (Regression Growth Evaluation Statin Study) to be a major determinant of promoter activity and plasma CETP concentration. In the present study, we have investigated the effects of the CETP promoter -1337 C>T and LIPC promoter -514 C>T polymorphisms on serum lipid profiles and risk of coronary atherosclerosis in 206 patients (154 males) with heterozygous FH (familial hypercholesterolaemia). To evaluate coronary atherosclerosis, we used CSI (coronary stenosis index) calculated from coronary angiograms. The CETP -1337 T allele was less frequent in subjects with a CSI > or =14 (mean value) in the group with coronary artery disease (P=0.04, as determined by chi(2) test). ANOVA revealed that HDL-C (high-density lipoprotein-cholesterol) and triacylglycerol (triglyceride) levels were not significantly higher in the presence of the CETP promoter -1337 T allele. Combined with LIPC promoter polymorphisms, HDL-C levels were highest and CSI were lowest with CETP -1337 CT+TT and LIPC -514 CC genotypes, but a significant interaction was not shown. A multiple logistic regression analysis revealed that, in patients with coronary atherosclerosis, the CETP- 1337 CC genotype was a significant genetic risk factor in FH (odds ratio=2.022; P=0.0256). These results indicate that the CETP promoter -1337C>T polymorphism is associated with the progression of coronary atherosclerosis in Japanese patients with FH, independent of HDL-C and triacylglycerol levels.     

Higher frequency of abnormal serum angiopoietin-like protein 3 than abnormal cholesteryl ester transfer protein in Japanese hyperalphalipoproteinemic subjects

BACKGROUND: Either a decrease of cholesteryl ester transfer protein (CETP) or an increase of angiopoietin-like protein 3 (ANGPTL3) in plasma has been shown to increase HDL-cholesterol (HDL-C) levels. However, as yet, it is not known which protein is more strongly associated with the modulation of HDL in the Japanese hyperalphalipoproteinemic (HALT) subjects. METHODS: The serum concentration of ANGPTL3 and CETP, together with total cholesterol (TC), triglycerides (TG), adiponectin and ApoE phenotypes were determined in three groups with different HDL-C concentrations: low, <40 mg/dl (n=51); normal, 40-90 mg/dl (n=126) and high, >90 mg/dl (n=89) in the average Japanese population. RESULTS: The normal range (mean+/-2SD) of serum ANGPTL3 (218+/-144 ng/ml) and CETP (1.29+/-0.90 microg/ml) were determined in cases with 40-90 mg/dl HDL-C concentration. The frequency of abnormally high ANGPTL3 cases (>362 ng/ml) were found to be significantly greater (44%) compared with those of low CETP cases (<0.39 microg/ml, 4.5%) in HALT cases (>90 mg/dl). ANGPTL3 showed a high correlation with HDL-C (r=0.67, P<0.0001) and adiponectin (r=0.57, P<0.0001), but not with CETP. CONCLUSION: In average Japanese population, abnormally higher frequency of increased ANGPTL3 prevail in HALT cases as compared with cases with low CETP. These findings suggest that ANGPTL3, the inhibitor of endothelial lipase, may be more strongly associated with increased HDL-C rather than CETP in plasma. Accordingly, ANGPTL3 seems to be a better target for the modulation of HDL-C.     

Genetic cholesteryl ester transfer protein deficiency caused by two prevalent mutations as a major determinant of increased levels of high density lipoprotein cholesterol.

Genetic determinants of HDL cholesterol (HDL-C) levels in the general population are poorly understood. We previously described plasma cholesteryl ester transfer protein (CETP) deficiency due to an intron 14 G(+1)-to-A mutation(Int14 A) in several families with very high HDL-C levels in Japan. Subjects with HDL-C > or = 100 mg/dl (n = 130) were screened by PCR single strand conformational polymorphism analysis of the CETP gene. Two other mutations were identified by DNA sequencing or primer-mediated restriction map modification of PCR products: a novel intron 14 splice donor site mutation caused by a T insertion at position +3 from the exon14/intron14 boundary (Int14 T) and a missense mutation (Asp442 to Gly) within exon 15 (D442G). The Int14 T mutation was only found in one family. However, the D442G and Int14 A mutations were highly prevalent in subjects with HDL-C > or = 60 mg/dl, with combined allele frequencies of 9%, 12%, 21% and 43% for HDL-C 60-79, 80-99, 100-119, and > or = 120 mg/dl, respectively. Furthermore, prevalences of the D442G and Int14 A mutations were extremely high in a general sample of Japanese men (n = 236), with heterozygote frequencies of 7% and 2%, respectively. These two mutations accounted for about 10% of the total variance of HDL-C in this population. The phenotype in a genetic compound heterozygote (Int14 T and Int14 A) was similar to that of Int14 A homozygotes (no detectable CETP and markedly increased HDL-C), indicating that the Int14 T produces a null allele. In four D442G homozygotes, mean HDL-C levels (86 +/- 26 mg/dl) were lower than in Int14 A homozygotes (158 +/- 35 mg/dl), reflecting residual CETP activity in plasma. In 47 D442G heterozygotes, mean HDL-C levels were 91 +/- 23 mg/dl, similar to the level in D442G homozygotes, and significantly greater than mean HDL-C levels in Int14 A heterozygotes (69 +/- 15 mg/dl). Thus, the D442G mutation acts differently to the null mutations with weaker effects on HDL in the homozygous state and stronger effects in the heterozygotes, suggesting dominant expression of a partially defective allele. CETP deficiency, reflecting two prevalent mutations (D442G and Int14 A), is the first example of a genetic deficiency state which is sufficiently common to explain a significant fraction of the variation in HDL-C in the general population.     

Therapeutic elevation of HDL-cholesterol to prevent atherosclerosis and coronary heart disease

Innovative pharmacological approaches to raise anti-atherogenic high-density lipoprotein-cholesterol (HDL-C) are currently of considerable interest, particularly in atherogenic dyslipidemias characterized by low levels of HDL-C, such as type 2 diabetes, the metabolic syndrome, and mixed dyslipidemia, but equally among individuals with or at elevated risk for premature cardiovascular disease (CVD). Epidemiological and observational studies first demonstrated that HDL-C was a strong, independent predictor of coronary heart disease (CHD) risk, and suggested that raising HDL-C levels might afford clinical benefit. Accumulating data from clinical trials of pharmacological agents that raise HDL-C levels have supported this concept. In addition to the pivotal role that HDL-C plays in reverse cholesterol transport and cellular cholesterol efflux, HDL particles possess a spectrum of anti-inflammatory, anti-oxidative, anti-apoptotic, anti-thrombotic, vasodilatory and anti-infectious properties, all of which potentially contribute to their atheroprotective nature. Significantly, anti-atherogenic properties of HDL particles are attenuated in common metabolic diseases that are characterized by subnormal HDL-C levels, such as type 2 diabetes and metabolic syndrome. Inhibition of cholesteryl ester transfer protein (CETP), a key player in cholesterol metabolism and transport, constitutes an innovative target for HDL-C raising. In lipid efficacy trials, 2 CETP inhibitors-JTT-705 and torcetrapib-induced marked elevation in HDL-C levels, with torcetrapib displaying greater efficacy. Moreover, both agents attenuate aortic atherosclerosis in cholesterol-fed rabbits. Clinical trial data demonstrating the clinical benefits of these drugs on atherosclerosis and CHD are eagerly awaited.     

非高密度脂蛋白胆固醇与系统性红斑狼疮颈动脉内膜中层厚度的相关性研究

目的探讨血清非高密度脂蛋白胆固醇（non-HDL-C）与系统性红斑狼疮（SLE）颈动脉内膜中层厚度（IMT）之间的关系。方法对42例SLE患者进行颈动脉超声检测IMT,按照IMT结果将其分为IMT阳性组（1MT≥0．85mm）和IMT阴性组（IMT〈0．85mm）;选取30例健康者为对照组。分别测定2组总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白胆固醇（HDL—C）及低密度脂蛋白胆固醇（LDL-C）,通过Frost法计算出non-HDL-C,并进行比较分析。结果①与对照组相比,SLE组呈现出高TG（t’=2．92,P=0．03）、高TC（t’=2．72,P=0．005）、低HDL-C（t=-6．221。P=0．000）,且non-HDL-c（t=4．875,P=0．000）值明显升高。②IMT阳性组血清HDL-C及non-HDL-C值明显高于IMT阴性组（P〈0．01）。③SLE患者的IMT与non-HDL-C呈正相关（r=0．426,P=0．000）,与HDL-C呈负相关（r=-2．450,P=0．018）,其中以non-HDL-C相关性最强。结论高血清non-HDL-C是SLE动脉粥样硬化的危险指标,血清non-HDL-C检测是评价和预测SLE动脉粥样硬化的可信指标。     

Low-dose, time-release nicotinic acid: effects in selected patients with low concentrations of high-density lipoprotein cholesterol.

In a retrospective analysis, 63 participants in a cardiac rehabilitation-preventive cardiology program were identified as having low blood concentrations (mean, 34 mg/dl) of high-density lipoprotein cholesterol (HDL-C) and a mean total cholesterol level of 223 mg/dl after 3 months of hygienic measures (aerobic exercise, avoidance of tobacco, diet, and weight loss) designed to increase the HDL-C level. These patients (treatment group) were treated with low-dose, time-release nicotinic acid (mean, 1,297 mg/day) for a mean duration of 7.4 months. All subjects were able to take the drug without intolerable side effects. Fifty-four patients similar to those in the treatment group participated in the same program but were not treated with nicotinic acid (control group). Exercise, diet, body weight, and smoking remained stable throughout the period of observation. For the treatment group, HDL-C levels increased a mean of 18% (+6 mg/dl), total cholesterol concentrations decreased 9% (-20 mg/dl), the ratio of total cholesterol to HDL-C decreased 25% (from 6.8 to 5.1), low-density lipoprotein cholesterol levels decreased 13% (-20 mg/dl), and triglyceride levels decreased 20% (from 165 mg/dl to 132 mg/dl). Aspartate aminotransferase and uric acid concentrations were minimally increased after treatment, and the blood glucose level was unchanged. In the control group, HDL-C levels increased a mean of 8% (+3 mg/dl) and the other blood lipid variables were not improved after a mean of 8.3 additional months of diet and exercise.(ABSTRACT TRUNCATED AT 250 WORDS)     

Elevated remnant-like lipoprotein particles in impaired glucose tolerance and type 2 diabetic patients.

OBJECTIVE: Impaired glucose tolerance (IGT) in association with insulin resistance is considered to be a risk factor for atherosclerosis. Thus, patients with IGT may have abnormal lipid and lipoprotein profiles. The purpose of this study was to investigate presence of remnant-type hyperlipoproteinemia in patients with IGT. RESEARCH DESIGN AND METHODS: Serum levels of remnant-like lipoprotein particles (RLP) were measured in 541 subjects (362 men and 179 women, age 53 +/- 7.9 years) who visited our health center for routine medical examinations. We measured RLP cholesterol (RLP-C) and RLP triglycerides (RLP-TG) using immunoaffinity gel containing monoclonal anti-human apoproteins A-I (H-12) and B-100 (JI-H) antibodies. After a 75-g oral glucose tolerance test, subjects were divided into three groups: normal, IGT, and type 2 diabetic. RESULTS: After matching for sex, age, and body weight, serum RLP-C in normal, IGT, and diabetic groups were 4.2 +/- 1.7, 6.2 +/- 3.4, and 6.2 +/- 4.2 mg/dl, respectively. The corresponding RLP-TG values were 16.7 +/- 9.2, 28.0 +/- 19.1, and 29.0 +/- 27.2 mg/dl. We found that RLP-C and RLP-TG values were significantly higher in the IGT and diabetic groups compared with the normal group (P < 0.001). In the same order, total serum cholesterol levels were 206 +/- 29, 205 +/- 34, and 206 +/- 34 mg/dl and LDL cholesterol levels were 127 +/- 27, 124 +/- 34, and 123 +/- 34 mg/dl, showing no marked difference in these groups. However, serum levels of triglyceride were higher in the IGT and diabetes groups (155 +/- 76 and 151 +/- 81 mg/dl vs. 106 +/- 41 mg/dl; P < 0.0001). Further, the incidence of remnant hyperlipoproteinemia in normocholesterolemic subjects was up to four times higher in IGT and diabetic groups compared with the normal group. CONCLUSIONS: High serum RLP-C and RLP-TG levels in IGT and diabetic patients may represent an increased risk of atherosclerosis in these patients.     

CETP inhibition in cardiovascular risk management: a critical appraisal

In view of the cardioprotective effect of high-density lipoproteins (HDL) and the limited effects of statin and fibrate therapy on HDL cholesterol, it is clinically relevant to test whether pharmacological treatment aimed at raising HDL lowers cardiovascular risk. Cholesteryl ester transfer protein (CETP) is a new therapeutic target, because the cholesteryl ester transfer process lowers HDL cholesterol and contributes to an atherogenic lipoprotein profile, particularly when plasma triglycerides are high. Clinical evidence suggests that coronary artery calcification as well as intima media thickness is positively related to plasma cholesteryl ester transfer, and that high plasma CETP concentration is associated with increased cardiovascular risk in hypertriglyceridaemia. However, CETP could also have anti-atherogenic potential, since it provides a potentially beneficial route for delivery of HDL-derived cholesteryl esters to the liver. In addition, CETP could also favourably stimulate peripheral cell cholesterol removal and enhance hepatic cholesterol uptake. Recent evidence suggests that a high CETP level may confer lower cardiovascular risk in the context of low triglycerides. At maximal doses, the CETP inhibitors JTT-705 and torcetrapib elicit a marked rise in HDL cholesterol of up to 34% and 91-106%, respectively. The effectiveness of these drugs on (intermediate) clinical outcome measures is currently being tested in large-scale phase III clinical trials, with torcetrapib being only evaluated in combination therapy with atorvastatin. When and how to use CETP inhibitors, e.g. in combination with a statin or a fibrate, is a major challenge. We propose that low HDL cholesterol in the context of high triglycerides, such as found in type 2 diabetes mellitus, could become an important indication area for this new class of drugs.     

Validation of the Friedewald Equation for Evaluation of Plasma LDL-Cholesterol

In most clinical laboratories, low density lipoprotein (LDL) cholesterol is usually estimated indirectly with the Friedewald equation or directly with the N-geneous assay. We assessed LDL-cholesterol values obtained by both methods to find an appropriate fasting period and to assess the influence of the energy content of the last meal. Blood samples were taken from 28 healthy volunteers who had consumed a standard meal (107 g of carbohydrate, 658 kcal) followed by a fasting period of 12 and 18 h, or a high-energy meal (190 g of carbohydrate, 1011 kcal) with a fasting period of 12 h. Prolongation of the fasting period from 12 h to 18 h decreased glucose level, but did not decrease triacylglycerol, total cholesterol, or high density lipoprotein (HDL) cholesterol. LDL-cholesterol levels measured with the N-geneous assay did not change (94.0 +/- 21.5 to 96.3 +/- 19.1 mg/dl). LDL-cholesterol levels calculated with the Friedewald equation were also similar after fasting periods of 12 h (98.5 +/- 21.4 mg/dl) and 18 h (99.7 +/- 20.2 mg/dl). The high-energy meal did not change the level of LDL-cholesterol measured with the N-geneous assay (96.1 +/- 21.2 mg/dl), or the glucose, triacylglycerol, total cholesterol, or HDL-cholesterol level, but LDL-cholesterol levels evaluated from the Friedewald equation (92.6 +/- 20.3 mg/dl) became significantly lower. A fasting time longer than 12 h is not necessary to obtain reasonable blood lipid levels. The Friedewald equation gave higher LDL-cholesterol levels than N-geneous assay in young Japanese females who had eaten a low-energy meal, and lower values when they had eaten a high-energy meal. Thus, it may be necessary to pay attention to energy of nigh meal prior to blood withdrawal.     

Low-dose effect of simvastatin (MK-733) on serum lipids, lipoproteins, and apolipoproteins in patients with hypercholesterolemia

The effects of simvastatin (MK-733), a competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, on serum lipids, lipoproteins, and apolipoproteins were investigated in 29 patients (12 men, 17 women, aged 37 to 73) with moderate to severe hypercholesterolemia. It was given in doses of 2.5 mg/day for four months and 5 mg/day for the succeeding four months. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein (apo) B decreased by 18% (263 +/- 7 mg/dl to 216 +/- 7 mg/dl, P less than 0.01), 24% (180 +/- 7 mg/dl to 136 +/- 7 mg/dl, P less than 0.01), and 21% (133 +/- 4 mg/dl to 104 +/- 3 mg/dl, P less than 0.01), respectively, four months after treatment. Similar reductions (17%, 24%, and 23%, respectively, P less than 0.01) were observed at eight months. A significant reduction in triglyceride (TG) was observed (173 +/- 15 mg/dl to 136 +/- 11 mg/dl at eight months, P less than 0.01), as was a significant increase in serum high-density lipoprotein cholesterol (HDL-C) (48 +/- 2 mg/dl to 52 +/- 2 mg/dl at eight months, P less than 0.01). However, apo AI and apo AII remained unchanged. Atherogenic indices of (TC--HDL-C)/ HDL-C, LDL-C/HDL-C, and apo B/Apo AI ratios were significantly (P less than 0.01) reduced after treatment. No significant changes were observed in lipoprotein lipase, hepatic TG lipase, and lecithin: cholesterol acyltransferase (LCAT) activities. Simvastatin was well tolerated and no critical side effects were noted in the eight-month study period. These data indicate that simvastatin, even at a low dose of 2.5 to 5 mg daily, causes consistent reductions in serum TC, LDL-C, apo B, and TG, and a rise in HDL-C and antiatherogenic lipoproteins.     

Cholesteryl ester transfer protein promotes the formation of cholesterol-rich remnant like lipoprotein particles in human plasma

BACKGROUND: Cholesteryl ester transfer protein (CETP) is suggested to be involved in the cholesterol level in remnant like lipoprotein particles (RLP), but there is no direct evidence that CETP increases cholesterol-rich RLP in plasma. METHODS: Human plasma was incubated with or without HDL containing [(3)H]-labeled cholesteryl ester ([(3)H]CE), recombinant CETP or CETP inhibitors at 37 degrees C in vitro. RESULTS: The RLP-cholesterol (RLP-C) level increased time-dependently and the amount of RLP-C increase (DeltaRLP-C) by the incubation was positively correlated with triglyceride (TG) level in plasma (r=0.597, P=0.0070). [(3)H]CE in HDL was transferred to RLP fraction under 37 degrees C incubation, and the amount of [(3)H]CE transferred to RLP correlated significantly with DeltaRLP-C in plasma (r=0.611, P=0.0156). Human recombinant CETP enhanced the RLP-C increase, while CETP inhibitor JTT-705 and anti-human CETP monoclonal antibody inhibited both the RLP-C increase and [(3)H]CE transfer to RLP. On the other hand, an inhibition of lecithin: cholesterol acyltransferase (LCAT) did not affect the RLP-C increase. In triglyceride-rich lipoproteins (TRL) fraction, JTT-705 inhibited [(3)H]CE transfer to RLP more strongly than that to non-RLP. CONCLUSIONS: CETP promotes the formation of cholesterol-rich RLP through the transfer of CE from HDL to TRL and CETP inhibitors are useful to reduce RLP-C.     

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.     

Lipoprotein composition and HDL particle size distribution in women with non-insulin-dependent diabetes mellitus and the effects of probucol treatment

To further characterize the spectrum of potentially atherogenic disturbances in lipoprotein composition in non-insulin-dependent diabetes mellitus (NIDDM), we have studied a subset of women with NIDDM before and after treatment with the lipophilic lipid-lowering drug probucol (1 gm day), which we have shown corrects certain compositional abnormalities these women share with subjects who have hypercholesterolemia. Before treatment, the NIDDM group had a somewhat higher plasma triglyceride level (154 +/- 58.3 mg/dl, vs control, 80.0 +/- 21 mg/dl [mean +/- SD]; p less than 0.025) than controls but their cholesterol and high-density lipoprotein cholesterol (HDL-C) levels did not differ from control levels. A number of significant disturbances, however, were present in the surface and core lipid composition of their lipoproteins. Although the cholesterol content of NIDDM low-density lipoprotein (LDL) was similar to that of controls, its content of sphingomyelin and phosphatidylinositol plus phosphatidylserine and sphingomyelin-to-lecithin ratio all were significantly reduced. Moreover, their very-low-density lipoprotein (VLDL) and HDL2 tended to have reduced amounts of free (unesterified) cholesterol (FC) relative to lecithin, and their HDL2 and HDL3 tended to be triglyceride enriched. Probucol therapy resulted in significant decreases in total plasma cholesterol (-15%), FC (-28%), HDL-C (-22%), and triglyceride (-16%) and in apoproteins A-I, B, and E (apo A-I, B, and E), without changing diabetic control (before probucol: hemoglobin A1, cholesterol, 10.7% +/- 2.7%; after probucol: 10.9% +/- 3.0%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Increased apo A-I and apo A-II fractional catabolic rate in patients with low high density lipoprotein-cholesterol levels with or without hypertriglyceridemia.

Low HDL-cholesterol (HDL-C) levels may elevate atherosclerosis risk, and often associate with hypertriglyceridemia (HTG); however, the metabolic causes of low HDL-C levels with or without HTG are poorly understood. We studied the turnover of radioiodinated HDL apolipoproteins, apo A-I and apo A-II, in 15 human subjects with low HDL-C, six with normal plasma TG levels (group 1) and nine with high TG (group 2), and compared them to 13 control subjects with normal HDL-C and TG levels (group 3). The fractional catabolic rate (FCR) was equally elevated in groups 1 and 2 vs. group 3 for both apo A-I (0.313 +/- 0.052 and 0.323 +/- 0.063 vs. 0.245 +/- 0.043 pools/d, P = 0.003) and apo A-II (0.213 +/- 0.036 and 0.239 +/- 0.037 vs. 0.185 +/- 0.031 pools/d, P = 0.006). Thus, high FCR characterized low HDL-C regardless of the presence or absence of HTG. In contrast, transport rate (TR) of apo A-I did not differ significantly among the groups and the apo A-II TR differed only between groups 2 and 3 (2.15 +/- 0.57, 2.50 +/- 0.39, and 1.83 +/- 0.48 mg/kg per d for groups 1 to 3, respectively, P = 0.016). Several HDL-related factors were similar in groups 1 and 2 but differed in group 3, as with FCR, including the ratio of lipoprotein lipase to hepatic lipase activity (LPL/HL) in post-heparin plasma, the ratio of the HDL-C to apo A-I plus apo A-II levels, and the percent of tracer in the d greater than 1.21 fraction. In linear regression analysis HDL-C levels correlated inversely with the FCR of apo A-I and apo A-II (r = -0.74, P less than 0.0001 for both). Major correlates of FCR were HDL-C/apo A-I + apo A-II, LPL/HL, and plasma TG levels. We hypothesize that lipase activity and plasma TG affect HDL composition which modulates FCR, which in turn regulates HDL-C. Thus, HTG is only one of several factors which may contribute to elevated FCR and low HDL-C. Given the relationship of altered HDL composition with high FCR and low HDL-C levels, factors affecting HDL composition may increase atherosclerosis susceptibility.     

上海地区老年男性血脂参考值及其分布

目的分析60岁以上老年男性血清脂类水平的参考值及其分布。方法752名健康老年男性按年龄分组,先按年龄5岁为组距分组并分析各血清脂类水平,根据统计结果重新分组。结果按不同年龄段之间的差异分为3组,其中随年龄增长,致动脉粥样硬化的脂类下降,抗动脉粥样硬化脂类成分上升。在不同年龄组间三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)、载脂蛋白A-I(apo A-I)、载脂蛋白B(apo B)、非高密度脂蛋白胆固醇(non-HDL-C)差异有统计学意义,调查人群各指标的95%范围分别为:胆固醇(Chol)3.18～6.60 mmol/L,TG 0.66～3.66 mmol/L,HDL-C>0.92 mmol/L,低密度脂蛋白胆固醇(LDL-C)1.22～4.16 mmol/L,apo A-I0.91～1.65 g/L,apo B 0.56～1.34 g/L,non-HDL-C 1.87～5.13 mmol/L,LDL/LDL-apo B>1.07。结论老年人群的血脂合适范围较一般人群升高,特别是TG水平,在临床应用时应按不同年龄段选用恰当的合适范围。     

'Trig-onometry': non-high-density lipoprotein cholesterol as a therapeutic target in dyslipidaemia

Targeting elevations in low-density lipoprotein cholesterol (LDL-C) remains the cornerstone of cardiovascular prevention. However, this fraction does not adequately capture elevated triglyceride-rich lipoproteins (TRLs; e.g. intermediate-density lipoprotein, very low density lipoprotein) in certain patients with metabolic syndrome or diabetic dyslipidaemia. Many such individuals have residual cardiovascular risk that might be lipid/lipoprotein related despite therapy with first-line agents (statins). Epidemiological evidence encompassing > 100,000 persons supports the contention that non-high-density lipoprotein cholesterol (non-HDL-C) is a superior risk factor vs. LDL-C for incident coronary heart disease (CHD) in certain patient populations. In studies with clinical end-points evaluated in the current article, a 1:1 to 1:3 relationship was observed between reductions in non-HDL-C and in the relative risk of CHD after long-term treatment with statins, niacin (nicotinic acid) and fibric-acid derivatives (fibrates); this relationship increased to 1:5 to 1:10 in smaller subgroups of patients with elevated triglycerides and low HDL-C levels. Treatment with statin-, niacin-, fibrate-, ezetimibe-, and omega 3 fatty acid-containing regimens reduced non-HDL-C by approximately 9-65%. In a range of clinical trials, long-term treatment with these agents also significantly decreased the incidence of clinical/angiographic/imaging efficacy outcome variables. For patients with dyslipidaemia, consensus guidelines have established non-HDL-C treatment targets 30 mg/dl higher than LDL-C goals. Ongoing prospective randomised controlled trials should help to resolve controversies concerning (i) the clinical utility of targeting non-HDL-C in patients with dyslipidaemia; (ii) the most efficacious and well-tolerated therapies to reduce non-HDL-C (e.g. combination regimens); and (iii) associations between such reductions and clinical, angiographic, and/or imaging end-points.     

Variation at the cholesteryl ester transfer protein gene in relation to plasma high density lipoproteins cholesterol levels and carotid intima-media thickness

BACKGROUND: Cholesteryl ester transfer protein (CETP) plays a major role in lipoprotein metabolism. We have screened the CETP gene for mutations and polymorphisms regulating high density lipoproteins cholesterol (HDL-C) levels and the development of atherosclerosis, and found some polymorphisms (I405V and R451Q) to have minor effects. DESIGN: The purpose of this study was to investigate the combined effect of the several polymorphisms of the CETP gene so far found on HDL-C levels and carotid intima-media thickness (IMT), and, in addition, to study whether the recently found functional polymorphism in the promoter region of the CETP gene (C to A, - 629 relative to the first transcribed nucleotide) explains the previous associations due to linkage disequilibrium. The genotypes were determined in a population sample of 481 men and women. RESULTS: There were no significant differences in plasma CETP activity or carotid IMT between the genotypes of the promoter polymorphism. The women with the CC genotype of the promoter polymorphism had the lowest HDL-C levels (P < 0.001), but no such difference was seen in men. Detected polymorphisms of the CETP gene explained about 8% of the variation in HDL-C in women and about 7 and 10% of the variation in carotid IMT in women and men, respectively. The associations of the promoter, I405V and R451Q-A373P polymorphisms with HDL-C and carotid IMT seemed to be independent of each other. The associations with IMT were independent of total HDL-C levels, suggesting that HDL subfractions may have more effect on IMT. CONCLUSION: The CETP gene locus was found to be polymorphic and its polymorphisms explained a reasonable proportion of the variation in the degree of carotid atherosclerosis.     

Xanthelasma: clinical indicator of decreased levels of high-density lipoprotein cholesterol

The fasting plasma lipid and lipoprotein levels were measured prospectively in 41 consecutive patients with xanthelasma seen over a four-year period. The study group included 25 women and 16 men with mean ages of 60 and 56 years, respectively. Each patient had clinical evaluation for medications or illnesses that might affect plasma lipid levels before entry into the study. The most striking lipid abnormality was the preponderance of decreased levels of high-density lipoprotein cholesterol (HDL-C). In 94% of the study population, HDL-C values were less than the mean values of the age-matched reference population. For men the mean HDL-C level was 30.8 mg/dl (vs 45 mg/dl in the reference population, P less than .001); for women the mean HDL-C level was 33 mg/dl (vs 50 mg/dl, P less than .001). The total cholesterol, low-density lipoprotein, and triglyceride levels of those in the study were not significantly different from those of the patients in the reference population. Evaluation of cardiac risk based solely on HDL-C levels showed 80% of the study population to have three to four times the average risk. This study points out the high probability of decreased HDL-C levels in patients with xanthelasma. Since the level of HDL-C has been shown to be inversely related to the incidence of cardiovascular disease, it may be prudent to evaluate HDL-C levels and do a thorough cardiovascular evaluation in patients with xanthelasma.     

非酒精性脂肪肝患者血清非高密度脂蛋白胆固醇水平检测分析

目的了解非酒精性脂肪肝患者血清非高密度脂蛋白胆固醇(non-HDL-C)代谢水平,评价其临床应用价值。方法通过对单位体检者的影像学检查及肝功能、血糖、血脂等血清生化指标检测,并对其中非酒精性脂肪肝与体检健康者(对照组)进行比较。结果脂肪肝总检出率为9.15%,男性检出率12.50%,显著高于女性的5.99%(P<0.05);男性患者丙氨酸转氨酶(ALT)、间接胆红素(IBil)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、载脂蛋白A1(apoA1)、non-HDL-C、apoB100/apoA1、LDL-C/HDL-C、apoB100/HDL-C、总胆固醇/高密度脂蛋白胆固醇(TC/HDL-C)等与对照组比较差异具有统计学意义(P<0.05或P<0.01),女性患者天冬氨酸转氨酶(AST)、总胆红素(TBil)、直接胆红素(DBil)I、Bil、葡萄糖(Glu)、TC、TG、LDL-C、apoA1、non-HDL-C、apoB100/apoA1、LDL-C/HDL-C、apoB100/HDL-C、TC/HDL-C与对照组比较差异具有统计学意义(P<0.05或P<0.01);non-HDL-C与TC、LDL-C、TG、HDL-C、apoA1、apoB100、apoB100/apoA1、TC/HDL均显著相关(r=0.411~0.989,P<0.01)。结论非酒精性脂肪肝普遍具有脂类代谢异常和肝脏受损特点,non-HDL-C的检测有助于全面了解非酒精性脂肪肝脂类代谢状况。     

阿托伐他汀对急性冠状动脉综合症患者血清sdLDL-C的影响

目的探讨阿托伐他汀对急性冠状动脉综合症（ACS）患者治疗前、后血清小而密低密度脂蛋白胆固醇（sdLDL—C）水平的影响。方法选取初发ACS患者131例及同期中老年健康体检者178名,记录受试者一般情况,给予ACS患者口服阿托伐他汀（10mg／d）调脂治疗,检测受试者治疗前、后血脂水平及血清sdLDL—C水平。统计分析受试者治疗前、后各指标的差异。结果健康对照人群血清sdLDL—C水平第95百分位数为0．62mmol／L。调脂治疗后,ACS患者血清总胆固醇（TC）、三酰甘油（TG）、高密度脂蛋白胆固醇（HDL—C）、低密度脂蛋白胆固醇（LDL—C）、非高密度脂蛋白胆固醇（non—HDL—C）、TC／HDL—C比值和sdLDL—C水平与治疗前比较差异有统计学意义（P〈0．05）。治疗后sdLDL—C降低程度与治疗前血清TC、TG、LDL—C和non—HDL—C水平显著相关[相关系数（r）分别为0．329（P〈0．001）、0．320（P〈0．001）、0．232（P=0．013）、0．385（P〈0．001）],与HDL—C水平和TC／HDL—C比值之间无相关性[r分别为一0．155（P=0．100）、0．046（P=0．624）]。LDL—C〈2．59mmol／L的ACS患者调脂治疗后血清sdLDL—C明显降低（P〈0．05）,sdLDL—C异常率由治疗前的26．9％下降到8．6％,二者比较差异有统计学意义（P〈0．05）。结论常规阿托伐他汀调脂治疗可降低ACS患者血清sdLDL—C水平,亦可明显降低血脂水平正常的冠心病患者sdLDL—C异常率。