Lipid parameters for measuring risk of cardiovascular disease

Interactions of Lipid Genetic Risk Scores With Estimates of Metabolic Health in a Danish Population

Background—

There are several well-established lifestyle factors influencing dyslipidemia and currently; 157 genetic susceptibility loci have been reported to be associated with serum lipid levels at genome-wide statistical significance. However, the interplay between lifestyle risk factors and these susceptibility loci has not been fully elucidated. We tested whether genetic risk scores (GRS) of lipid-associated single nucleotide polymorphisms associate with fasting serum lipid traits and whether the effects are modulated by lifestyle factors or estimates of metabolic health.

Methods and Results—

The single nucleotide polymorphisms were genotyped in 2 Danish cohorts: inter99 (n=5961) for discovery analyses and Health2006 (n=2565) for replication. On the basis of published effect sizes of single nucleotide polymorphisms associated with circulating fasting levels of total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, or triglyceride, 4 weighted GRS were constructed. In a cross-sectional design, we investigated whether the effect of these weighted GRSs on lipid levels were modulated by diet, alcohol consumption, physical activity, and smoking or the individual metabolic health status as estimated from body mass index, waist circumference, and insulin resistance assessed using homeostasis model assessment of insulin resistance. All 4 lipid weighted GRSs associated strongly with their respective trait (from P =3.3×10 –69 to P =1.1×10 –123 ). We found interactions between the triglyceride weighted GRS and body mass index and waist circumference on fasting triglyceride levels in Inter99 and replicated these findings in Health2006 ( P interaction =9.8×10 –5 and 2.0×10 –5 , respectively, in combined analysis).

Conclusions—

Our findings suggest that individuals who are obese may be more susceptible to the cumulative genetic burden of triglyceride single nucleotide polymorphisms. Therefore, it is suggested that especially these genetically at-risk individuals may benefit more from targeted interventions aiming at obesity prevention.

The Human Blood Metabolome-Transcriptome Interface

Biological systems consist of multiple organizational levels all densely interacting with each other to ensure function and flexibility of the system. Simultaneous analysis of cross-sectional multi-omics data from large population studies is a powerful tool to comprehensively characterize the underlying molecular mechanisms on a physiological scale. In this study, we systematically analyzed the relationship between fasting serum metabolomics and whole blood transcriptomics data from 712 individuals of the German KORA F4 cohort. Correlation-based analysis identified 1,109 significant associations between 522 transcripts and 114 metabolites summarized in an integrated network, the 'human blood metabolome-transcriptome interface' (BMTI). Bidirectional causality analysis using Mendelian randomization did not yield any statistically significant causal associations between transcripts and metabolites. A knowledge-based interpretation and integration with a genome-scale human metabolic reconstruction revealed systematic signatures of signaling, transport and metabolic processes, i.e. metabolic reactions mainly belonging to lipid, energy and amino acid metabolism. Moreover, the construction of a network based on functional categories illustrated the cross-talk between the biological layers at a pathway level. Using a transcription factor binding site enrichment analysis, this pathway cross-talk was further confirmed at a regulatory level. Finally, we demonstrated how the constructed networks can be used to gain novel insights into molecular mechanisms associated to intermediate clinical traits. Overall, our results demonstrate the utility of a multi-omics integrative approach to understand the molecular mechanisms underlying both normal physiology and disease.

Sleep apnea is independently associated with peripheral arterial disease in the Hispanic Community Health Study/Study of Latinos

OBJECTIVE

Sleep apnea (SA) has been linked with various forms of cardiovascular disease, but little is known about its association with peripheral artery disease (PAD) measured using the ankle-brachial index. This relationship was evaluated in the Hispanic Community Health Study/Study of Latinos.

APPROACH AND RESULTS

We studied 8367 Hispanic Community Health Study/Study of Latinos participants who were 45 to 74 years of age. Sleep symptoms were examined with the self-reported Sleep Health Questionnaire. SA was assessed using an in-home sleep study. Systolic blood pressure was measured in all extremities to compute the ankle-brachial index. PAD was defined as ankle-brachial index <0.90 in either leg. Multivariable logistic regression was used to investigate the association between moderate-to-severe SA, defined as apnea-hypopnea index ≥15, and the presence of PAD. Analyses were adjusted for covariates. The prevalence of PAD was 4.7% (n=390). The mean apnea-hypopnea index was significantly higher among adults with PAD compared with those without (11.1 versus 8.6 events/h; P=0.046). After adjusting for covariates, moderate-to-severe SA was associated with a 70% increase in the odds of PAD (odds ratio, 1.7; 95% confidence interval, 1.1-2.5; P=0.0152). This association was not modified by sex (P=0.8739). However, there was evidence that the association between moderate-to-severe SA and PAD varied by Hispanic/Latino background (P<0.01). Specifically, the odds were stronger in Mexican (adjusted odds ratio, 2.9; 95% confidence interval, 1.3-6.2) and in Puerto Rican Americans (adjusted odds ratio, 2.0; 95% confidence interval, 0.97-4.2) than in other backgrounds.

CONCLUSIONS

Moderate-to-severe SA is associated with higher odds of PAD in Hispanic/Latino adults.

Revisiting the dyslipidemia associated with acute leukemia

BACKGROUND

Previous studies appreciate the leukemia-associated alterations in plasma lipid profiles but fail to provide a consistent pattern of lipid anomalies in leukemia patients. These inconsistencies could be due to overlooking the effects of related confounding risk-factors and comorbidities.

METHODS

The plasma lipid profiles of acute-leukemia and control groups were compared.

RESULTS

We observed that acute lymphocytic leukemia (ALL) patients display significantly higher triglycerides and very low-density lipoproteins, whereas, acute myeloid leukemia (AML) patients display significantly lower high-density lipoproteins. To assess the confounding effects of related risk factors gender-, age- and BMI-based analyses were performed. We observed that the aforementioned significant differences in the lipid profiles of leukemia patients were restricted to female participants of the respective groups. Moreover, a significant decrease in total cholesterol and low-density lipoprotein levels was observed only in male participants of the AML population. Various age-specific trends in plasma lipid profile of the leukemia patients were also observed. BMI-based analysis did not display many significant differences from the overall analyses. In addition to comparing the absolute values of plasma lipids in leukemia and control groups we also compared and observed significant differences in prevalence of various isolated- and mixed-dyslipidemias in these groups.

CONCLUSIONS

These findings may help in outlining the prevalence and types of dyslipidemia in leukemia patients that may emerge as diagnostic/prognostic factors for the management of acute leukemia.

A New Integrated Clinical-Biohumoral Model to Predict Functionally Significant Coronary Artery Disease in Patients With Chronic Chest Pain

BACKGROUND

In patients with chronic angina-like chest pain, the probability of coronary artery disease (CAD) is estimated by symptoms, age, and sex according to the Genders clinical model. We investigated the incremental value of circulating biomarkers over the Genders model to predict functionally significant CAD in patients with chronic chest pain.

METHODS

In 527 patients (60.4 years, standard deviation, 8.9 years; 61.3% male participants) enrolled in the European Evaluation of Integrated Cardiac Imaging (EVINCI) study, clinical and biohumoral data were collected.

RESULTS

Functionally significant CAD-ie, obstructive coronary disease seen at invasive angiography causing myocardial ischemia at stress imaging or associated with reduced fractional flow reserve (FFR < 0.8), or both-was present in 15.2% of patients. High-density lipoprotein (HDL) cholesterol, aspartate aminotransferase (AST) levels, and high-sensitivity C-reactive protein (hs-CRP) were the only independent predictors of disease among 31 biomarkers analyzed. The model integrating these biohumoral markers with clinical variables outperformed the Genders model by receiver operating characteristic curve (ROC) (area under the curve [AUC], 0.70 [standard error (SE), 0.03] vs 0.58 [SE, 0.03], respectively, P < 0.001) and reclassification analysis (net reclassification improvement, 0.15 [SE, 0.07]; P = 0.04). Cross-validation of the ROC analysis confirmed the discrimination ability of the new model (AUC, 0.66). As many as 56% of patients who were assigned to a higher pretest probability by the Genders model were correctly reassigned to a low probability class (< 15%) by the new integrated model.

CONCLUSIONS

The Genders model has a low accuracy for predicting functionally significant CAD. A new model integrating HDL cholesterol, AST, and hs-CRP levels with common clinical variables has a higher predictive accuracy for functionally significant CAD and allows the reclassification of patients from an intermediate/high to a low pretest likelihood of CAD.

Association between lipid ratios and insulin resistance in a Chinese population

AIM

To explore the association of lipid ratios and triglyceride (TG) with insulin resistance (IR) in a Chinese population. We also provide the clinical utility of lipid ratios to identify men and women with IR.

METHODS

This cross-sectional study included 614 men and 1055 women without diabetes. Insulin resistance was defined by homeostatic model assessment of IR > 2.69. Lipid ratios included the TG/ high density lipoprotein cholesterol (HDL-C), the total cholesterol (TC)/HDL-C and the low density lipoprotein cholesterol (LDL-C)/HDL -C. Logistic regression models and accurate estimates of the area under the receiver operating characteristic (AUROC) curves were obtained.

RESULTS

In normal-weight men, none of lipid ratios nor TG was associated with IR. In overweight/obese men, normal-weight women and overweight/obese women, the TG/HDL-C, the TC/HDL-C and TG were significantly associated with IR, and the associations were independent of waist circumference. All of the AUROCs for the TG/HDL-C and TG were > 0.7. The AUROCs for TC/HDL-C ratio were 0.69-0.77. The optimal cut-offs for TG/HDL-C were 1.51 in men and 0.84 in women. The optimal cut-offs for TG were 1.78 mmol/L in men and 1.49 mmol/L in women, respectively. In men, the optimal cut-off for LDL-C/HDL-C is 3.80. In women, the optimal cut-off for LDL-C/HDL-C is 3.82.

CONCLUSION

The TG/HDL-C, the TC/HDL-C and TG are associated with IR in overweight/obese men, normal-weight and overweight/obese women. The LDL-C/HDL-C is only associated with IR in normal-weight women. The TG/HDL-C and TG might be used as surrogate markers for assessing IR.

Proteomic analysis of the palmitate-induced myotube secretome reveals involvement of the annexin A1-formyl peptide receptor 2 (FPR2) pathway in insulin resistance

Elevated levels of the free fatty acid palmitate are found in the plasma of obese patients and induce insulin resistance. Skeletal muscle secretes myokines as extracellular signaling mediators in response to pathophysiological conditions. Here, we identified and characterized the skeletal muscle secretome in response to palmitate-induced insulin resistance. Using a quantitative proteomic approach, we identified 36 secretory proteins modulated by palmitate-induced insulin resistance. Bioinformatics analysis revealed that palmitate-induced insulin resistance induced cellular stress and modulated secretory events. We found that the decrease in the level of annexin A1, a secretory protein, depended on palmitate, and that annexin A1 and its receptor, formyl peptide receptor 2 agonist, played a protective role in the palmitate-induced insulin resistance of L6 myotubes through PKC-θ modulation. In mice fed with a high-fat diet, treatment with the formyl peptide receptor 2 agonist improved systemic insulin sensitivity. Thus, we identified myokine candidates modulated by palmitate-induced insulin resistance and found that the annexin A1- formyl peptide receptor 2 pathway mediated the insulin resistance of skeletal muscle, as well as systemic insulin sensitivity.

Gender-specific pathway differences in the human serum metabolome

The susceptibility for various diseases as well as the response to treatments differ considerably between men and women. As a basis for a gender-specific personalized healthcare, an extensive characterization of the molecular differences between the two genders is required. In the present study, we conducted a large-scale metabolomics analysis of 507 metabolic markers measured in serum of 1756 participants from the German KORA F4 study (903 females and 853 males). One-third of the metabolites show significant differences between males and females. A pathway analysis revealed strong differences in steroid metabolism, fatty acids and further lipids, a large fraction of amino acids, oxidative phosphorylation, purine metabolism and gamma-glutamyl dipeptides. We then extended this analysis by a network-based clustering approach. Metabolite interactions were estimated using Gaussian graphical models to get an unbiased, fully data-driven metabolic network representation. This approach is not limited to possibly arbitrary pathway boundaries and can even include poorly or uncharacterized metabolites. The network analysis revealed several strongly gender-regulated submodules across different pathways. Finally, a gender-stratified genome-wide association study was performed to determine whether the observed gender differences are caused by dimorphisms in the effects of genetic polymorphisms on the metabolome. With only a single genome-wide significant hit, our results suggest that this scenario is not the case. In summary, we report an extensive characterization and interpretation of gender-specific differences of the human serum metabolome, providing a broad basis for future analyses.

Epidemiology: disease associations and modulators of HDL-related biomarkers

Epidemiological studies have shown an inverse association between high-density lipoprotein cholesterol (HDL-C) levels and risk of ischemic heart disease. In addition, a low level of HDL-C has been shown to be a risk factor for other diseases not related to atherosclerosis. However, recent studies have not supported a causal effect of HDL-C in the development of atherosclerosis. Furthermore, new drugs markedly elevating HDL-C levels have been disappointing with respect to clinical endpoints. Earlier, most studies have focused almost exclusively on the total HDL-C without regard to the chemical composition or multiple subclasses of HDL particles. Recently, there have been efforts to dissect the HDL fraction into as many well-defined subfractions and individual molecules of HDL particles as possible. On the other hand, the focus is shifting from the structure and composition to the function of HDL particles. Biomarkers and mechanisms that could potentially explain the beneficial characteristics of HDL particles unrelated to their cholesterol content have been sought with sophisticated methods such as proteomics, lipidomics, metabonomics, and function studies including efflux capacity. These new approaches have been used in order to resolve the complex effects of diseases, conditions, environmental factors, and genes in relation to the protective role of HDL but high-throughput methods are still needed for large-scale epidemiological studies.

The clinical burden of type 2 diabetes in patients with acute coronary syndromes: prognosis and implications for short- and long-term management

Type 2 diabetes mellitus (T2DM) is associated with increased morbidity and mortality in patients with acute coronary syndromes (ACS). Cardiometabolic risk factors, including hyperglycaemia, insulin resistance, atherogenic dyslipidaemia, increased visceral fat and inflammation, are associated with increased risk in this population and represent potential targets for treatment. In this review, management strategies for patients with T2DM post-ACS, both in the acute-care setting and in the long-term, are discussed. Although the benefits of long-term, aggressive, multifactorial risk factor modification are well established, a significant burden of recurrent events remains and the search for novel strategies continues. Several studies are assessing the potential cardiovascular (CV) benefits and safety of various classes of newer agents. Of these, AleCardio (aleglitazar), Examination of Cardiovascular Outcomes With Alogliptin versus Standard of Care in Patients With Type 2 Diabetes Mellitus and Acute Coronary Syndrome (EXAMINE; alogliptin) and Evaluation of LIXisenatide in Acute Coronary Syndrome (ELIXA; lixisenatide) specifically address patients with type 2 diabetes post-ACS. The mechanisms of action of these new therapies and aims of the CV outcome studies are briefly reviewed. The prevalence of type 2 diabetes continues to increase worldwide highlighting the need for new strategies that address the complex underlying processes that drive atherosclerosis and CV events in this high-risk patient population.

Are generic and brand-name statins clinically equivalent? Evidence from a real data-base

BACKGROUND

Use of generic drugs can help contain drug spending. However, there is concern among patients and physicians that generic drugs may be clinically inferior to brand-name ones. This study aimed to compare patients treated with generic and brand-name statins in terms of therapeutic interruption and cardiovascular (CV) outcomes.

METHODS

13,799 beneficiaries of the health care system of Lombardy, Italy, aged 40 years or older who were newly treated with generic or brand-name simvastatin during 2008, were followed until 2011 for the occurrence of two outcomes: 1) therapeutic discontinuation and 2) hospitalization for CV events. Hazard ratios (HR) associated with use of generic or brand-name at starting therapy (intention-to-treat analysis) and during follow-up (as-treated analysis) were estimated by fitting proportional hazard Cox models. A Monte-Carlo sensitivity analysis was performed to account for unmeasured confounders.

RESULTS

Patients who started on generic did not experience a different risk of discontinuation (HR: 0.98; 95% CI 0.94 to 1.02) nor of CV outcomes (HR: 0.98; 95% CI 0.79 to 1.22) from those starting on brand-name. Patients who spent >75% of time of follow-up with statin available on generics did not experience a different risk of discontinuation (HR: 0.94; 95% CI 0.87 to 1.01), nor of CV outcomes (HR: 1.06; 95% CI 0.83 to 1.34), compared with those who mainly or only used brand-name statin.

CONCLUSIONS

Our findings do not support the notion that in the real world clinical practice brand-name statins are superior to generics for keeping therapy and preventing CV outcomes.

A rare variant in APOC3 is associated with plasma triglyceride and VLDL levels in Europeans

The analysis of rich catalogues of genetic variation from population-based sequencing provides an opportunity to screen for functional effects. Here we report a rare variant in APOC3 (rs138326449-A, minor allele frequency ~0.25% (UK)) associated with plasma triglyceride (TG) levels (-1.43 s.d. (s.e.=0.27 per minor allele (P-value=8.0 × 10(-8))) discovered in 3,202 individuals with low read-depth, whole-genome sequence. We replicate this in 12,831 participants from five additional samples of Northern and Southern European origin (-1.0 s.d. (s.e.=0.173), P-value=7.32 × 10(-9)). This is consistent with an effect between 0.5 and 1.5 mmol l(-1) dependent on population. We show that a single predicted splice donor variant is responsible for association signals and is independent of known common variants. Analyses suggest an independent relationship between rs138326449 and high-density lipoprotein (HDL) levels. This represents one of the first examples of a rare, large effect variant identified from whole-genome sequencing at a population scale.

Multiple associated variants increase the heritability explained for plasma lipids and coronary artery disease

BACKGROUND

Plasma lipid levels as well as coronary artery disease (CAD) have been shown to be highly heritable with estimates ranging from 40% to 60%. However, top variants detected by large-scale genome-wide association studies explain only a fraction of the total variance in plasma lipid phenotypes and CAD.

METHODS AND RESULTS

We performed a conditional and joint association analysis using summary-level statistics from 2 large genome-wide association meta-analyses: the Global Lipids Genetics Consortium (GLGC) study, and the Coronary Artery Disease Genome-Wide Replication and Meta-Analysis (CARDIoGRAM) study. There were 100 184 individuals from 46 GLGC studies for plasma lipids, and 22 233 cases and 64 762 controls from 14 studies for CAD. We detected several loci where multiple independent single-nucleotide polymorphisms were associated with lipid traits within a locus (12 out of 33 loci for high-density lipoprotein cholesterol, 10 of 35 loci for low-density lipoprotein cholesterol, 13 of 44 loci for total cholesterol, and 8 of 28 loci for triglycerides), reaching genome-wide significance (P<5×10(-8)), nearly doubling the heritability explained by genome-wide association studies (from 3.6 to 7.6% for high-density lipoprotein cholesterol, from 5.0 to 8.8% for low-density lipoprotein cholesterol, from 5.5 to 8.8% for total cholesterol, and from 5.7 to 8.5% for triglycerides). Multiple single-nucleotide polymorphisms were also associated with CAD (3 of 15 loci; an increase from 9.6% to 11.4% of heritability explained).

CONCLUSIONS

These results demonstrate that a portion of the missing heritability for lipid traits and CAD can be explained by multiple variants at each locus.

Exploring developmental and physiological functions of fatty acid and lipid variants through worm and fly genetics

Lipids are more than biomolecules for energy storage and membrane structure. With ample structural variation, lipids critically participate in nearly all aspects of cellular function. Lipid homeostasis and metabolism are closely related to major human diseases and health problems. However, lipid functional studies have been significantly underdeveloped, partly because of the difficulty in applying genetics and common molecular approaches to tackle the complexity associated with lipid biosynthesis, metabolism, and function. In the past decade, a number of laboratories began to analyze the roles of lipid metabolism in development and other physiological functions using animal models and combining genetics, genomics, and biochemical approaches. These pioneering efforts have not only provided valuable insights regarding lipid functions in vivo but have also established feasible methodology for future studies. Here, we review a subset of these studies using Caenorhabditis elegans and Drosophila melanogaster.

Lipoprotein particle profiles compared with standard lipids in association with coronary artery calcification in the general Japanese population

OBJECTIVE

The utility of lipoprotein particle profiles measured by nuclear magnetic resonance (NMR) spectroscopy beyond standard serum lipids remains inconclusive. Furthermore, few studies have compared NMR measurements with standard lipids in association with coronary artery calcification (CAC) in Japanese, where the coronary atherosclerotic burden is low. We examined whether NMR-based lipoprotein particle profiles are associated with CAC, and compared them with standard lipid and lipid ratios in the Japanese general population.

METHODS AND RESULTS

We conducted a cross-sectional study in 851 men aged 40-79 years without cardiovascular diseases and lipid-lowering therapies. Adjusted odds ratios (ORs) (95% confidence intervals) for the top versus the bottom quartile of NMR-measured particle concentrations were 2.01 (1.24-3.23) for low-density lipoprotein (LDL-P), 1.04 (0.62-1.75) for high-density lipoprotein (HDL-P), 1.82 (1.13-2.95) for very-low-density lipoprotein (VLDL-P), and 1.92 (1.18-3.17) for LDL-P/HDL-P ratio. Similarly adjusted ORs of NMR-measured particle sizes were 0.59 (0.36-0.97) for LDL-P, 0.66 (0.40-1.10) for HDL-P, and 0.67 (0.40-1.12) for VLDL-P. The corresponding ORs were 1.82 (1.14-2.90) for total cholesterol (TC), 2.06 (1.28-3.30) for low-density lipoprotein cholesterol (LDL-C), 0.56 (0.34-0.91) for high-density lipoprotein cholesterol (HDL-C), 2.02 (1.24-3.29) for triglycerides, 2.08 (1.29-3.36) for non-high-density lipoprotein cholesterol (non-HDL-C), 2.27 (1.37-3.78) for TC/HDL-C ratio, and 1.73 (1.06-2.85) for LDL-C/HDL-C ratio. After mutual adjustment for total LDL-P concentration and TC/HDL-C ratio or non-HDL-C, LDL-P was no longer associated, whereas TC/HDL-C ratio remained significantly associated with CAC.

CONCLUSIONS

In community-based Japanese men, the overall association of CAC with NMR-measured lipoprotein indices is comparable, but not superior, to that with standard lipids.

Atherogenic dyslipidemia

Atherogenic dyslipidemia (AD) refers to elevated levels of triglycerides (TG) and small-dense low-density lipoprotein and low levels of high-density lipoprotein cholesterol (HDL-C). In addition, elevated levels of large TG rich very low-density lipoproteins, apolipoprotein B and oxidised low-density lipoprotein (LDL), and reduced levels of small high-density lipoproteins plays a critical role in AD. All three elements of AD per se have been recognised as independent risk factor for cardiovascular disease. LDL-C/HDL-C ratio has shown excellent risk prediction of coronary heart disease than either of the two risk markers. Asian Indians have a higher prevalence of AD than western population due to higher physical inactivity, low exercise and diet deficient in polyunsaturated fatty acids (PUFA). The AD can be well managed by therapeutic lifestyle changes with increased physical activities, regular exercise, and diets low in carbohydrates and high in PUFA such as omega-3-fatty acids, as the primary intervention. This can be supplemented drug therapies such as statin monotherapy or combination therapy with niacin/fibrates. Rosuvastatin is the only statin, presently available, to effectively treat AD in diabetes and MS patients.

Diet and blood lipids in 1-4 year-old children

BACKGROUND AND AIM

Early nutrition may programme blood lipid levels and thereby later cardiovascular health of children. The objective here was to evaluate the effects of maternal dietary counselling during pregnancy and breastfeeding on dietary intakes and blood lipid values in 1-4 year-old children. Further, the nutritional determinants of children's lipid profiles were assessed.

METHODS AND RESULTS

Mothers were randomised into dietary counselling or control groups at the first trimester of pregnancy. Their children were followed up clinically at 1, 2 and 4 years of age, by three-day food records and analyses of total cholesterol, HDL cholesterol and apolipoproteins A-I and B as well as lipoprotein (a). In general, the mean intake of saturated fatty acids as a proportion of total energy intake (E%) was higher than the recommended, while the mean intake of polyunsaturated fatty acids was low in children's diet. Over the first years, girls had higher concentration of non-HDL cholesterol than boys; 2.64 mmol/l (95% CI 2.54-2.74) vs. 2.49 (2.38-2.60); p = 0.038. Maternal dietary counselling was not reflected in the children's lipid values. Children's monounsaturated fatty acid intake (E%) correlated with apoA-I (p = 0.048) and, furthermore, there was a negative correlation between polyunsaturated fatty acid intake (E%) and apoB (p = 0.046).

CONCLUSION

Children's dietary fatty acid intake, but not maternal dietary counselling was shown to be related to blood apolipoproteins in children.

The role of triglyceride in cardiovascular disease in asian patients with type 2 diabetes--a systematic review

In Asian populations, diabetes mellitus is increasing and has become an important health problem in recent decades. Cardiovascular disease (CVD) is one of the most important complications and the most common cause of death in diabetic patients. Among the risk factors of CVD, elevated low-density lipoprotein cholesterol has been a major concern. Studies suggested that serum triglyceride may also play a role in predicting CVD in patients with type 2 diabetes mellitus, but the association is still debated. In this review, we summarized published studies focusing on the relationship between serum triglyceride and CVD disease in Asian diabetic patients. Ten studies conducted in six different Asian countries (three from Hong Kong, two from Taiwan, tow from Japan, one from Indonesia, one from South India, and one from South Korea) were summarized and discussed. CVD was subdivided into coronary heart disease, stroke, and peripheral arterial disease. Of the ten studies analyzed, one focused on CVD, five on coronary heart disease, three on stroke, three on peripheral arterial disease, and one on mortality from CVD. Studies from Hong Kong, Taiwan, and Japan suggested that triglyceride is a significant and independent risk factor for coronary heart disease, but not a significant risk factor for stroke (studies conducted in Japan and South Korea) or peripheral arterial disease (studies conducted in Taiwan, Indonesia, and South India). Although serum triglyceride may be a significant risk factor for coronary heart disease in Asian diabetic patients, clinical trials evaluating whether lowering triglycerides using fibrates can reduce the risk of coronary heart disease in these patients need to be initiated.

Particle numbers of lipoprotein subclasses and arterial stiffness among middle-aged men from the ERA JUMP study

We examined the association between serum lipoprotein subclasses and the three measures of arterial stiffness, that is, (i) carotid-femoral pulse wave velocity (cfPWV), which is a gold standard measure of central arterial stiffness, (ii) brachial-ankle PWV (baPWV), which is emerging as a combined measure of central and peripheral arterial stiffness and (iii) femoral-ankle PWV (faPWV), which is a measure of peripheral arterial stiffness. Among a population-based sample of 701 apparently healthy Caucasian, Japanese American and Korean men aged 40-49 years, concentrations of lipoprotein particles were assessed by nuclear magnetic resonance (NMR) spectroscopy, and the PWV was assessed with an automated waveform analyzer (VP2000, Omron, Japan). Multiple linear regressions were performed to analyse the association between each NMR lipoprotein subclasses and PWV measures, after adjusting for cardiovascular risk factors and other confounders. A cutoff of P<0.01 was used for determining significance. All PWV measures had significant correlations with total and small low-density lipoprotein particle number (LDL-P) (all P<0.0001) but not LDL cholesterol (LDL-C) (all P>0.1), independent of race and age. In multivariate regression analysis, no NMR lipoprotein subclass was significantly associated with cfPWV (all P>0.01). However, most NMR lipoprotein subclasses had significant associations with both baPWV and faPWV (P<0.01). In this study of healthy middle-aged men, as compared with cfPWV, both baPWV and faPWV had stronger associations with particle numbers of lipoprotein subclasses. Our results may suggest that both baPWV and faPWV are related to arterial stiffness and atherosclerosis, whereas cfPWV may represent arterial stiffness alone.

Risk scores of common genetic variants for lipid levels influence atherosclerosis and incident coronary heart disease

OBJECTIVE

Circulating levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, and triglycerides are recognized risk factors for cardiovascular disease. We tested the hypothesis that the cumulative effects of common genetic variants for lipids are collectively associated with subclinical atherosclerosis and incident coronary heart disease.

APPROACH AND RESULTS

Participants were drawn from the Erasmus Rucphen Family Study (n=2269) and the Rotterdam Study (n=8130). Linear regression and Cox proportional hazards models were applied to assess the influence of 4 risk scores derived from common genetic variants for lipids (total cholesterol, LDL-C, high-density lipoprotein cholesterol, and triglycerides) on carotid plaque, intima-media thickness, incident myocardial infarction, and coronary heart disease. Adjusted for age and sex, all 4 risk scores were associated with carotid plaque. This relationship was the strongest for the LDL-C score, which increased plaque score by 0.102 per SD increase in genetic risk score (P=3.2 × 10(-8)). The LDL-C score was also nominally associated with intima-media thickness, which increased 0.006 mm per SD increase in score (P=0.05). Both the total cholesterol and LDL-C scores were associated with incident myocardial infarction and coronary heart disease with hazard ratios between 1.10 and 1.13 per SD increase in score. Inclusion of additional risk factors as covariates minimally affected these results.

CONCLUSIONS

Common genetic variants with small effects on lipid levels are, in combination, significantly associated with subclinical and clinical cardiovascular outcomes. As knowledge of genetic variation increases, preclinical genetic screening tools might enhance the prediction and prevention of clinical events.

Pathobiology of obstructive sleep apnea-related dyslipidemia: focus on the liver

Obstructive sleep apnea and dyslipidemia are common medical disorders that independently increase vascular morbidity and mortality. Current animal and human data show that, indeed, obstructive sleep apnea may mediate pathological alterations in cholesterol and triglyceride metabolism. The mechanisms involved are increased lipolysis, decreased lipoprotein clearance, and enhanced lipid output from the liver. Human evidence shows that the treatment of obstructive sleep apnea with continuous positive airway pressure leads to an improvement of postprandial hyperlipidemia. However, more studies are needed, to clarify the pathophysiology of the interrelationship between obstructive sleep apnea and dyslipidemia and whether treatment of obstructive sleep apnea will lead to an improvement in the lipid profile and, more importantly, reduce hyperlipidemia-related vascular outcomes.

Gene-centric meta-analysis of lipid traits in African, East Asian and Hispanic populations

Meta-analyses of European populations has successfully identified genetic variants in over 100 loci associated with lipid levels, but our knowledge in other ethnicities remains limited. To address this, we performed dense genotyping of ∼2,000 candidate genes in 7,657 African Americans, 1,315 Hispanics and 841 East Asians, using the IBC array, a custom ∼50,000 SNP genotyping array. Meta-analyses confirmed 16 lipid loci previously established in European populations at genome-wide significance level, and found multiple independent association signals within these lipid loci. Initial discovery and in silico follow-up in 7,000 additional African American samples, confirmed two novel loci: rs5030359 within ICAM1 is associated with total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) (p = 8.8×10(-7) and p = 1.5×10(-6) respectively) and a nonsense mutation rs3211938 within CD36 is associated with high-density lipoprotein cholesterol (HDL-C) levels (p = 13.5×10(-12)). The rs3211938-G allele, which is nearly absent in European and Asian populations, has been previously found to be associated with CD36 deficiency and shows a signature of selection in Africans and African Americans. Finally, we have evaluated the effect of SNPs established in European populations on lipid levels in multi-ethnic populations and show that most known lipid association signals span across ethnicities. However, differences between populations, especially differences in allele frequency, can be leveraged to identify novel signals, as shown by the discovery of ICAM1 and CD36 in the current report.

A common variant highly associated with plasma VEGFA levels also contributes to the variation of both LDL-C and HDL-C

Vascular endothelial growth factor A (VEGFA) is among the most-significant stimulators of angiogenesis. Its effect on cardiovascular diseases and on the variation of related risk factors such as lipid parameters is considered important, although as yet unclear. Recently, we identified four common variants (rs6921438, rs4416670, rs6993770, and rs10738760) that explain up to 50% of the heritability of plasma VEGFA levels. In the present study, we aimed at assessing the contribution of these variants to the variation of blood lipid levels (including apoE, triglycerides, total cholesterol, low- and high-density lipoprotein cholesterol levels (LDL-C and HDL-C)] in healthy subjects. The effect of these single-nucleotide polymorphisms (SNPs) on lipid levels was assessed using linear regression in discovery and replication samples (n = 1,006 and n = 1,145; respectively), followed by a meta-analysis. Their gene×gene and gene×environment interactions were also assessed. SNP rs6921438 was associated with HDL-C (β = -0.08 mmol/l, P(overall) = 1.2 × 10(-7)) and LDL-C (β = 0.13 mmol/l, P(overall) = 1.5 × 10(-4)). We also identified a significant association between the interaction rs4416670×hypertension and apoE variation (P(overall) = 1.7 × 10(-5)). Therefore, our present study shows a common genetic regulation between VEGFA and cholesterol homeostasis molecules. The SNP rs6921438 is in linkage disequilibrium with variants located in an enhancer- and promoter-associated histone mark region and could have a regulatory effect in the expression of surrounding genes, including VEGFA.

Large-scale gene-centric meta-analysis across 32 studies identifies multiple lipid loci

Genome-wide association studies (GWASs) have identified many SNPs underlying variations in plasma-lipid levels. We explore whether additional loci associated with plasma-lipid phenotypes, such as high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglycerides (TGs), can be identified by a dense gene-centric approach. Our meta-analysis of 32 studies in 66,240 individuals of European ancestry was based on the custom ∼50,000 SNP genotyping array (the ITMAT-Broad-CARe array) covering ∼2,000 candidate genes. SNP-lipid associations were replicated either in a cohort comprising an additional 24,736 samples or within the Global Lipid Genetic Consortium. We identified four, six, ten, and four unreported SNPs in established lipid genes for HDL-C, LDL-C, TC, and TGs, respectively. We also identified several lipid-related SNPs in previously unreported genes: DGAT2, HCAR2, GPIHBP1, PPARG, and FTO for HDL-C; SOCS3, APOH, SPTY2D1, BRCA2, and VLDLR for LDL-C; SOCS3, UGT1A1, BRCA2, UBE3B, FCGR2A, CHUK, and INSIG2 for TC; and SERPINF2, C4B, GCK, GATA4, INSR, and LPAL2 for TGs. The proportion of explained phenotypic variance in the subset of studies providing individual-level data was 9.9% for HDL-C, 9.5% for LDL-C, 10.3% for TC, and 8.0% for TGs. This large meta-analysis of lipid phenotypes with the use of a dense gene-centric approach identified multiple SNPs not previously described in established lipid genes and several previously unknown loci. The explained phenotypic variance from this approach was comparable to that from a meta-analysis of GWAS data, suggesting that a focused genotyping approach can further increase the understanding of heritability of plasma lipids.

Population-based risk factors for elevated alanine aminotransferase in a South Texas Mexican-American population

BACKGROUND AND AIMS

Elevated alanine aminotransferase (ALT >40 IU/mL) is a marker of liver injury but provides little insight into etiology. We aimed to identify and stratify risk factors associated with elevated ALT in a randomly selected population with a high prevalence of elevated ALT (39%), obesity (49%) and diabetes (30%).

METHODS

Two machine learning methods, the support vector machine (SVM) and Bayesian logistic regression (BLR), were used to capture risk factors in a community cohort of 1532 adults from the Cameron County Hispanic Cohort (CCHC). A total of 28 predictor variables were used in the prediction models. The recently identified genetic marker rs738409 on the PNPLA3 gene was genotyped using the Sequenom iPLEX assay.

RESULTS

The four major risk factors for elevated ALT were fasting plasma insulin level and insulin resistance, increased BMI and total body weight, plasma triglycerides and non-HDL cholesterol, and diastolic hypertension. In spite of the highly significant association of rs738409 in females, the role of rs738409 in the prediction model is minimal, compared to other epidemiological risk factors. Age and drug and alcohol consumption were not independent determinants of elevated ALT in this analysis.

CONCLUSIONS

The risk factors most strongly associated with elevated ALT in this population are components of the metabolic syndrome and point to nonalcoholic fatty liver disease (NAFLD). This population-based model identifies the likely cause of liver disease without the requirement of individual pathological diagnosis of liver diseases. Use of such a model can greatly contribute to a population-based approach to prevention of liver disease.

Anti-obesity effect of a standardised ethanol extract from Curcuma longa L. fermented with Aspergillus oryzae in ob/ob mice and primary mouse adipocytes

BACKGROUND

We examined the anti-obesity effect of fermented Curcuma longa L. (turmeric) standardised ethanol extract (FTE) in the C57BL/6J ob/ob mouse model. Mice were fed a chow diet containing FTE (0, 200, or 500 mg kg⁻¹ body weight) for 9 weeks.

RESULTS

Supplementation with FTE significantly reduced body weight gain and retroperitoneal and epididymal adipose tissue weights compared to the ob/ob control group. Additionally, total cholesterol and triglyceride levels in serum and liver were significantly decreased in FTE-200 and FTE-500 groups when compared to those of the ob/ob control group, whereas the high-density lipoprotein-cholesterol level was significantly increased. The levels of serum adiponectin as well as mRNA expression of lipases, such as hormone sensitive lipase and adipose triglyceride lipase, were clearly increased. In primary adipocytes of C57BL/6J mice, FTE treatment caused a significant increase glycerol release and hormone sensitive lipase levels and decreased perilipin A levels.

CONCLUSION

These results suggest that supplementation of FTE has potent anti-obesity effects by controlling body weight, fat mass, serum lipids, and hepatic lipids. Moreover, FTE could be considered a potential resource for the treatment of obesity through its promotion of lipolysis via the protein kinase A pathway.

The protective effects of green tea polyphenols: lipid profile, inflammation, and antioxidant capacity in rats fed an atherogenic diet and dextran sodium sulfate

Acute and chronic inflammation and dyslipidemia play a critical role in the development of various diseases, including cardiovascular disease. Green tea polyphenols possess potent antioxidative and anti-inflammatory properties that contribute to the beneficial effects on heart health. The present study was carried out to determine if administration of a green tea extract (Polyphenon(®) E [PPE]; Mitsui Norin Co., Ltd., Tokyo, Japan) at 0.2% in the diet reduces cardiovascular risk factors, including dyslipidemia, inflammation, adiposity, and oxidative stress, in rats fed an atherogenic (high fat, cholesterol, and sugar) diet with dextran sodium sulfate (DSS) in drinking water. DSS treatment increased serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, C-reactive proteins (CRP), and markers of liver toxicity and decreased high-density lipoprotein (HDL)-cholesterol significantly. Adding PPE to the atherogenic diet (PPE-diet) was associated with lower total cholesterol and LDL-cholesterol (P<.001) and increased HDL-cholesterol (P=.001). In addition, the PPE-diet was associated with decreased serum CRP concentration (P=.023) and increased total antioxidant capacity (P=.016) and catalase (P=.001) and glutathione peroxidase (P=.050) activities. The PPE-diet significantly lowered epididymal fat pad weight (P=.009). Feeding the PPE-diet also ameliorated some of the DSS-induced lipid, inflammatory, and oxidative symptoms. In summary, green tea supplementation decreased several cardiovascular risk factors, including body composition, dyslipidemia, inflammatory status, and antioxidant capacity, in rats fed an atherogenic diet. This study supports green tea as an effective dietary component for sustaining cardiovascular health.

Lipid-related markers and cardiovascular disease prediction

CONTEXT

The value of assessing various emerging lipid-related markers for prediction of first cardiovascular events is debated.

OBJECTIVE

To determine whether adding information on apolipoprotein B and apolipoprotein A-I, lipoprotein(a), or lipoprotein-associated phospholipase A2 to total cholesterol and high-density lipoprotein cholesterol (HDL-C) improves cardiovascular disease (CVD) risk prediction.

DESIGN, SETTING, AND PARTICIPANTS

Individual records were available for 165,544 participants without baseline CVD in 37 prospective cohorts (calendar years of recruitment: 1968-2007) with up to 15,126 incident fatal or nonfatal CVD outcomes (10,132 CHD and 4994 stroke outcomes) during a median follow-up of 10.4 years (interquartile range, 7.6-14 years).

MAIN OUTCOME MEASURES

Discrimination of CVD outcomes and reclassification of participants across predicted 10-year risk categories of low (<10%), intermediate (10%-<20%), and high (≥20%) risk.

RESULTS

The addition of information on various lipid-related markers to total cholesterol, HDL-C, and other conventional risk factors yielded improvement in the model's discrimination: C-index change, 0.0006 (95% CI, 0.0002-0.0009) for the combination of apolipoprotein B and A-I; 0.0016 (95% CI, 0.0009-0.0023) for lipoprotein(a); and 0.0018 (95% CI, 0.0010-0.0026) for lipoprotein-associated phospholipase A2 mass. Net reclassification improvements were less than 1% with the addition of each of these markers to risk scores containing conventional risk factors. We estimated that for 100,000 adults aged 40 years or older, 15,436 would be initially classified at intermediate risk using conventional risk factors alone. Additional testing with a combination of apolipoprotein B and A-I would reclassify 1.1%; lipoprotein(a), 4.1%; and lipoprotein-associated phospholipase A2 mass, 2.7% of people to a 20% or higher predicted CVD risk category and, therefore, in need of statin treatment under Adult Treatment Panel III guidelines.

CONCLUSION

In a study of individuals without known CVD, the addition of information on the combination of apolipoprotein B and A-I, lipoprotein(a), or lipoprotein-associated phospholipase A2 mass to risk scores containing total cholesterol and HDL-C led to slight improvement in CVD prediction.

Comparison of various lipid variables as predictors of coronary heart disease in Japanese men and women with type 2 diabetes: subanalysis of the Japan Diabetes Complications Study

OBJECTIVE

To determine the best lipid variable to predict coronary heart disease (CHD) in Japanese patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Eligible Japanese men and women (1,771) aged 40-70 years with type 2 diabetes from 59 institutes nationwide were followed for a planned 8-year period. The performance of eight conventional lipid variables, i.e., total cholesterol (TC), LDL-cholesterol (LDLC), HDL-cholesterol (HDLC), triglycerides (TGs), non-HDLC, TC/HDLC ratio, LDLC/HDLC ratio, and TG/HDLC ratio, as predictors of incident CHD were evaluated by four methods: hazard ratio (HR) per one SD increment by multivariate Cox analysis, χ(2) likelihood ratio test, area under the receiver operating characteristic curve (AUC), and tertile analysis.

RESULTS

Although all variables significantly predicted CHD events in men, non-HDLC (HR per one SD 1.78 [95% CI 1.43-2.21]; AUC 0.726) and TC/HDLC (HR 1.63 [1.36-1.95]; AUC 0.718) had the better predictive performances among the variables, including LDLC. In women, TGs (log-transformed; HR 1.72 [1.21-2.43]; AUC 0.708) were the best predictor according to results of tertile analysis (HR of the top tertile versus the bottom tertile 4.31 [1.53-12.16]). The associations with incident CHD were linear and continuous.

CONCLUSIONS

For Japanese diabetic men, non-HDLC and TC/HDLC were the best predictors, whereas TGs were most predictive for women. These findings, which included prominent sex differences, should be considered among clinical approaches to risk reduction among East Asians with diabetes.

Leukotrienes as modifiers of preclinical atherosclerosis?

Preclinical atherosclerosis represents a crucial period associated with several pathophysiological reactions in the vascular wall. Failure to diagnose preclinical atherosclerosis at this stage misses a major opportunity to prevent the long-term consequences of this disease. Surrogate biological and structural vascular markers are available to determine the presence and the extension of preclinical vascular injury in the general population. Examples of surrogate markers are carotid intima media thickness and biomarkers including high-sensitivity C-reactive protein, cell adhesion molecules and matrix metalloproteinases, and leukotrienes. Recently, leukotrienes have been implicated as mediators, biomarkers, and possible therapeutic targets in the context of subclinical atherosclerosis. The aim of this short paper is to focus on the relation between preclinical atherosclerosis and leukotrienes, with particular attention to the recent development on the use of leukotriene modifiers in the treatment of atherosclerosis.

Lipids and lipoproteins and risk of different vascular events in the MRC/BHF Heart Protection Study

BACKGROUND

Low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol are established risk factors for vascular disease, but lipoprotein particle concentrations may be stronger determinants of risk.

METHODS AND RESULTS

Associations between vascular events and baseline concentrations of cholesterol fractions, apolipoproteins B and A(1), and lipoprotein particles assessed by nuclear magnetic resonance were considered in the Heart Protection Study randomized trial of simvastatin versus placebo (>5000 vascular events during 5.3 years of follow-up among 20 000 participants). Major occlusive coronary events were equally strongly associated with the cholesterol- and particle-based total LDL measures; adjusted hazard ratios per 1-SD-higher level were 1.25 (95% confidence interval [CI], 1.16-1.34) for LDL cholesterol, 1.22 (95% CI, 1.14-1.32) for non-HDL cholesterol, 1.23 (95% CI, 1.15-1.33) for apolipoprotein B, and 1.25 (95% CI, 1.16-1.35) for LDL particle number. Given the total LDL particle number, the distribution between small and large particles did not add predictive value. Associations of these different LDL-related measures were similar with arterial revascularization procedures but much weaker or nonexistent with ischemic stroke and other cardiac events (mainly heart failure). After adjustment for LDL particle number, the hazard ratios for major occlusive coronary event per 1-SD-higher level were 0.91 (95% CI, 0.86-0.96) for HDL cholesterol and 0.89 (95% CI, 0.85-0.93) for HDL particle number. Other cardiac events were inversely associated with total (hazard ratio, 0.84; 95% CI, 0.79-0.90) and small (0.82; 95% CI, 0.76-0.89) HDL particle number but only very weakly associated with HDL cholesterol (0.94; 95% CI, 0.88-1.00).

CONCLUSIONS

In a population at 2% average coronary event risk per year, cholesterol, apolipoprotein, and particle measures of LDL were strongly correlated and had similar predictive values for incident major occlusive vascular events. It is unclear whether the associations between HDL particle numbers and other cardiac events represent a causal or reverse-causal effect.

Normalization of visceral adiposity is required to normalize plasma apolipoprotein B levels in response to a healthy eating/physical activity lifestyle modification program in viscerally obese men

OBJECTIVE

Little is known about how visceral adipose tissue (VAT) influences circulating apolipoprotein B (apoB) levels, which reflect atherogenic risk. We have examined the effects of a 1-year lifestyle modification program on plasma apoB levels in viscerally obese men and compared post-intervention levels to those of a reference group of lean healthy men.

METHODS

Fasting plasma apoB levels were measured in 107 non-diabetic, viscerally obese men, before and after a 1-year lifestyle intervention program aiming at improving nutritional and physical activity/exercise habits.

RESULTS

After the intervention, subjects significantly decreased their volume of VAT (Δ = -26 ± 18%, p < 0.0001) measured by computed tomography and significantly, but modestly reduced their fasting apoB levels (Δ = -3 ± 14%, p = 0.04). When compared to the reference group, men in the intervention group still had higher apoB levels suggesting that they did not "normalize" their apoB concentrations to the level of the healthy non-obese reference men. To further explore the relationship between VAT and apoB, men in the intervention group were stratified according to quartiles of VAT achieved after the intervention. Only men of the lowest quartile of VAT (corresponding to 844 ± 42 cm(3), similar to the value of the reference group; 809 ± 52 cm(3) of VAT) showed plasma apoB levels which were similar to those of the reference group (0.98 ± 0.21 vs. 0.99 ± 0.24 g/L, NS, for lowest VAT quartile and reference group, respectively).

CONCLUSION

These results suggest that, in order to "normalize" apoB levels in response to a lifestyle modification program, viscerally obese dyslipidemic men need to achieve levels of VAT similar to healthy non-obese men.

Association of lipid and lipoprotein profiles with future development of type 2 diabetes in nondiabetic Korean subjects: a 4-year retrospective, longitudinal study

CONTEXT

Traditional lipid measures are known to be associated with incident type 2 diabetes.

OBJECTIVE

Our objective was to assess the independent association between lipid profiles and the development of type 2 diabetes in nondiabetic Korean subjects over a 4-yr period.

DESIGN AND METHODS

A total of 5577 Koreans without diabetes who underwent consecutive comprehensive health check-ups annually for 5 yr were enrolled. We measured concentrations of total cholesterol (TC), triglyceride (TG), apolipoprotein B (apoB), apolipoprotein A-I, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) and calculated lipid ratios. The association between incident type 2 diabetes and the initial values for lipid ratios and other lipoprotein components was examined.

RESULTS

Over the course of 4 yr, 330 subjects (5.9%) developed type 2 diabetes. TC, LDL-C, TG, non-HDL, apoB, apoB to apolipoprotein A-I ratio, TC to HDL ratio, TG to HDL ratio, LDL to HDL ratio and apoB to HDL ratio were associated with incident type 2 diabetes in multivariate analysis after adjustment for age and gender. Of these, the ratio of TC to HDL and apoB to HDL showed a significant association with increased risk of type 2 diabetes, compared with other lipoprotein parameters: odds ratio (1.340, 95% confidence interval 1.166-1.538; and 1.338, 95% confidence interval 1.162-1.540), respectively. The odds ratio for the development of type 2 diabetes increased significantly as the tertiles of the baseline ratio of TC to HDL and apoB to HDL increased from the first to the third tertile.

CONCLUSIONS

This study suggests that lipid and lipoprotein profiles can be independently associated with later development of type 2 diabetes in nondiabetic Korean adults in a longitudinal analysis.

Fetoplacental vascular endothelial dysfunction as an early phenomenon in the programming of human adult diseases in subjects born from gestational diabetes mellitus or obesity in pregnancy

Gestational diabetes mellitus (GDM) and obesity in pregnancy (OP) are pathological conditions associated with placenta vascular dysfunction coursing with metabolic changes at the fetoplacental microvascular and macrovascular endothelium. These alterations are seen as abnormal expression and activity of the cationic amino acid transporters and endothelial nitric oxide synthase isoform, that is, the "endothelial L-arginine/nitric oxide signalling pathway." Several studies suggest that the endogenous nucleoside adenosine along with insulin, and potentially arginases, are factors involved in GDM-, but much less information regards their role in OP-associated placental vascular alterations. There is convincing evidence that GDM and OP prone placental endothelium to an "altered metabolic state" leading to fetal programming evidenced at birth, a phenomenon associated with future development of chronic diseases. In this paper it is suggested that this pathological state could be considered as a metabolic marker that could predict occurrence of diseases in adulthood, such as cardiovascular disease, obesity, diabetes mellitus (including gestational diabetes), and metabolic syndrome.

Long-term curcumin administration protects against atherosclerosis via hepatic regulation of lipoprotein cholesterol metabolism

SCOPE

Atherosclerosis is a major cause of cardiovascular disease caused by high cholesterol. Stains are widely prescribed to lower cholesterol levels, but natural dietary compounds may also be effective. Therefore, we studied the effect of the natural dietary compound curcumin on atherosclerosis and its underlying mechanisms based on plasma and hepatic lipid metabolism.

METHODS AND RESULTS

LDLR(-/-) mice were fed a high-cholesterol diet and treated with curcumin, lovastatin or control (n=10 per group) for 18 wk. Aortic arch sections revealed curcumin ameliorated early atherosclerotic lesions, lipid infiltration, ICAM-1 and VCAM-1 localization, similar to lovastatin treatment. Furthermore, curcumin lowered plasma cholesterol, triglycerides, LDL cholesterol and Apo B levels as well as CETP activity, while curcumin increased plasma HDL cholesterol and liver Apo A-I expression, similar to lovastatin treatment. Curcumin caused transcriptional inhibition of HMG-CoA reductase, independent of ACAT1 and ACAT2 expression. Hepatic PPARα and LXRα expression was upregulated by curcumin treatment. Hepatic complement factor D (Cfd) and systemic CRP levels, markers of immune complement pathway activation, were significantly reduced by curcumin treatment.

CONCLUSION

Long-term curcumin treatment lowers plasma and hepatic cholesterol and suppresses early atherosclerotic lesions comparable to the protective effects of lovastatin. The anti-atherogenic effect of curcumin is mediated via multiple mechanisms including altered lipid, cholesterol and immune gene expression.

TO901317 regulating apolipoprotein M expression mediates via the farnesoid X receptor pathway in Caco-2 cells

Background

Apolipoprotein M (apoM) may have potential antiatherosclerotic properties. It has been reported that apoM expression could be regulated by many intracellar and extracellar factors. In the present study we further investigated regulation of apoM expression in Caco-2 cells stimulated by a liver X receptor (LXR) agonist, TO901317.

Materials and methods

Caco-2 cells were cultured in the presence of either TO901317, farnesoid X receptor (FXR) antagonist guggulsterone or TO901317 together with guggulsterone at different concentrations for 24 hrs. The mRNA levels of ATP-binding cassette transporter A1 (ABCA1), apoA1, apoM, liver receptor homologue-1 (LRH-1) and short heterodimer partner 1 (SHP1) were determined by real-time RT-PCR.

Results

When Caco-2 cell cultured with TO901317 alone, the mRNA levels of ABCA1, apoA1, apoM, LRH-1 and SHP1 were significantly increased with dose-dependent manners (p < 0.05), whereas when the cells cultured with guggulsterone alone, the mRNA levels of apoM, SHP1 and LRH-1 (p < 0.05) were strongly inhibited. Moreover, guggulsterone could abolish the TO901317 enhanced mRNA levels of apoA1 apoM, SHP1 and LRH-1.

Conclusion

The present study demonstrated that LXR agonist TO901317 induced apoM expression in Caco-2 cells might be mediated via the LXR/FXR pathway.