Leukemia cells display lower levels of intracellular cholesterol irrespective of the exogenous cholesterol availability

BACKGROUND

Different types of cancer cells are previously shown to accumulate intracellular cholesterol. However, the data on intracellular cholesterol levels in leukemia cells provide contradictory evidence. Various previous works indicate either increase, decrease or no difference in total cholesterol levels between leukemia cells and healthy peripheral blood mononuclear cells (PBMCs).

METHODS

We studied the intracellular cholesterol levels in acute myeloid leukemia (AML) and acute lymphocytic leukemia (ALL) cells and compared with that in PBMCs from the healthy subjects.

RESULTS

We observed that the PBMCs from AML (n=7) and ALL (n=7) patients displayed significantly lower intracellular levels of total cholesterol in comparison to PBMCs from the healthy subjects (n=26). Consistent with the patient data the ALL (CCRF-CEM and MOLT-3) and AML (KG-1 and THP-1) cell lines also displayed significantly lower intracellular levels of total cholesterol. We confirmed this observation using multiple methodological approaches. Both ALL and AML cell lines also displayed significantly lower levels of free cholesterol and cholesteryl ester contents in comparison to normal hematopoietic cells. We observed that >90% of the total cholesterol in leukemia cells as well as in normal PBMCs was present in the form of cholesteryl esters. It was also observed that the lower levels of cholesterol in leukemia cells are not affected by exogenous cholesterol availability.

CONCLUSIONS

Present study provides convincing evidence to prove that the cellular free cholesterol and cholesteryl ester content is significantly reduced in leukemia cells in comparison to normal hematopoietic cells in circulation. Moreover, it was shown that the lower levels of cholesterol in leukemia cells are not affected by exogenous cholesterol availability.

Comparison of lipid parameters to predict cardiovascular events in Japanese mild-to-moderate hypercholesterolemic patients with and without type 2 diabetes: Subanalysis of the MEGA study

AIMS

To determine whether specific lipid parameters are better predictors of cardiovascular disease (CVD) in Japanese mild-to-moderate hypercholesterolemic patients with and without diabetes.

METHODS

Mildly or moderately hypercholesterolemic patients with no history of CVD received diet therapy or diet therapy plus pravastatin. In this post-hoc subanalysis, 5-year data from 3170 patients (668 diabetes, 2502 non-diabetes) on diet therapy alone were used to compare lipid parameters as predictors of CVD. We examined the data by tertiles, using hazard ratio (HR) per one-standard deviation (SD) increment (decrease for high-density lipoprotein cholesterol, HDL-C), χ(2) value, receiver operating characteristic curve analysis, and spline analysis.

RESULTS

In mild-to-moderate hypercholesterolemic patients with diabetes, increased total cholesterol (TC)/HDL-C, low-density lipoprotein cholesterol (LDL-C)/HDL-C and decreased HDL-C were strongly associated with increased incidence of CVD (tertile analysis). In non-diabetes, increased non-HDL-C, and LDL-C/HDL-C were significantly associated with increased incidence of CVD. A one-SD decrease in HDL-C and a one-SD increment in non-HDL-C, TC/HDL-C, and LDL-C/HDL-C were significantly associated with increased HRs for CVD in both diabetes and non-diabetes. Linear CVD risk increases were found for non-HDL-C in diabetes and for non-HDL-C and HDL-C in non-diabetes (spline analysis).

CONCLUSIONS

In mild-to-moderate hypercholesterolemia, CVD risk prediction by stratifications of single or combination of traditional lipid parameter values illustrates various patterns. Parameters including HDL-C are better predictors of cardiovascular risk than only using TC or LDL-C alone. Non-HDL-C could be the most useful lipid parameter to assess CVD risk, considering it is easy to calculate and less affected by food intake.

Assessment of established HDL-C loci for association with HDL-C levels and type 2 diabetes in Pima Indians

AIMS/HYPOTHESIS

Epidemiological studies in Pima Indians identified elevated levels of HDL-cholesterol (HDL-C) as a protective factor against type 2 diabetes risk in women. We assessed whether HDL-C-associated single-nucleotide polymorphisms (SNPs) also associate with type 2 diabetes in female Pima Indians.

METHODS

Twenty-one SNPs in established HDL-C loci were initially analysed in 2,675 full-heritage Pima Indians. SNPs shown to associate with HDL-C (12 SNPs) were assessed for association with type 2 diabetes in 7,710 Pima Indians (55.6% female sex). The CETP locus provided the strongest evidence for association with HDL-C and was further interrogated by analysing tag SNPs.

RESULTS

Twelve of the 21 SNPs analysed had a significant association with HDL-C in Pima Indians; five SNPs representing four loci (CETP, DOCK6, PPP1R3B and ABCA1) reached genome-wide significance. Three SNPs, at CETP, KLF14 and HNF4A, associated with type 2 diabetes only in female participants with the HDL-C-lowering allele increasing diabetes risk (p values: 3.2 × 10(-4) to 7.7 × 10(-5)); the association remained significant even after adjustment for HDL-C. Additional analysis across CETP identified rs6499863 as having the strongest association with type 2 diabetes in female participants (p = 5.0 × 10(-6)) and this association remained independent of the HDL-C association.

CONCLUSIONS/INTERPRETATION

SNPs at the CETP, HNF4A and KLF14 locus are associated with HDL-C levels and type 2 diabetes (in female participants). However, since HNF4A and KLF14 are established loci for type 2 diabetes, it is unlikely that HDL-C solely mediates these associations.

Inverse relationship between high-density lipoprotein cholesterol raising and high-sensitivity C-reactive protein reduction in older patients treated with lipid-lowering therapy

BACKGROUND

Little is known regarding relationships between high-sensitivity C-reactive protein (hsCRP) and lipoproteins other than low-density lipoprotein cholesterol (LDL-C). High-density lipoprotein (HDL), with both anti-inflammatory and cholesterol-mediating effects, is of particular interest. This exploratory analysis assessed associations between hsCRP and lipids in older (>65 years) patients with moderate and/or high cardiovascular disease risk, before and after treatment with ezetimibe/simvastatin (E/S) or atorvastatin (ATV).

METHODS

An analysis of a multicenter, randomized, double-blind, 12-week study. Correlations were assessed in 1054 patients with both baseline and 12-week hsCRP ≤ 10 mg/L, pooled across doses of E/S (10/20 and 10/40 mg) and ATV (10, 20, and 40 mg), and combined E/S + ATV treatments. Because of multiple comparisons, observed relationships were considered significant only if P values were < .01.

RESULTS

Correlations between baseline levels of hsCRP and either LDL-C, non-HDL-C, or apolipoprotein B were weak and nonsignificant in the E/S, ATV, and E/S + ATV groups. After 12 weeks of treatment, these correlations increased slightly and significantly in all groups, except for LDL-C in the ATV group. HDL-C was significantly but inversely correlated with hsCRP in the ATV and E/S + ATV groups at baseline, and in all groups at 12 weeks. Only with HDL-C did change correlate with change in hsCRP in both the E/S and combined groups.

CONCLUSIONS

Relationships between hsCRP and lipid factors in older patients were weak at baseline and somewhat stronger after treatment. HDL-C was inversely and consistently correlated with baseline and 12-week on-treatment hsCRP and with therapy-induced changes in HDL-C and hsCRP.

Resequencing of the CETP gene in American whites and African blacks: Association of rare and common variants with HDL-cholesterol levels

BACKGROUND

Cholesteryl ester transfer protein (CETP) plays a crucial role in lipid metabolism. Associations of common CETP variants with variation in plasma lipid levels, and/or CETP mass/activity have been extensively studied and well-documented; however, the effects of uncommon/rare CETP variants on plasma lipid profile remain undefined. Hence, resequencing of the gene in extreme phenotypes and follow-up rare-variant association analyses are essential to fill this gap.

OBJECTIVE

To identify common and uncommon/rare variants in the CETP gene by resequencing the entire gene and test the effects of both common and uncommon/rare CETP variants on plasma lipid traits in two genetically distinct populations.

METHODS AND RESULTS

The entire CETP gene plus flanking regions were resequenced in 190 individuals comprising 95 non-Hispanic whites (NHWs) and 95 African blacks with extreme HDL-C levels. A total of 279 sequence variants were identified, of which 25 were novel. Selected variants were genotyped in the entire samples of 623 NHWs and 788 African blacks and 184 QC-passed variants were tested in relation to plasma lipid traits by using gene-based, single-site, haplotype and rare variant association analyses (SKAT-O). Two novel and independent associations of rs1968905 and rs289740 with HDL-C were identified in African blacks. Using SKAT-O analysis, we also identified rare variants with minor allele frequency <0.01 to be associated with HDL-C in both NHWs (P=0.024) and African blacks (P=0.009).

CONCLUSIONS

Our results point out that in addition to the common CETP variants, rare genetic variants in the CETP gene also contribute to the phenotypic variation of HDL-C in the general population.

Effects of Concentrated Pomegranate Juice on Subclinical Inflammation and Cardiometabolic Risk Factors for Type 2 Diabetes: A Quasi-Experimental Study

BACKGROUND

The health benefits of pomegranate juice have been reported in several studies. However, limited clinical trials have examined the effects of concentrated pomegranate juice (CPJ) on inflammatory factors.

OBJECTIVES

This study aimed to investigate the effects of CPJ on metabolic risk factors, including inflammatory biomarkers, in patients with type 2 diabetes mellitus.

PATIENTS AND METHODS

In a quasi-experiment trial, 40 type 2 diabetic patients were asked to consume 50 g of CPJ daily for 4 weeks. Anthropometric indices, dietary intake, blood pressure measurements, and fasting blood samples were conducted at baseline and 4 weeks after the intervention.

RESULTS

The intake of CPJ produced a significant increase in both total and high-density lipoprotein cholesterol (HDL-C) (4.7% and 3.9%, respectively) from baseline (P < 0.05). However, changes that were observed in serum triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), fasting blood glucose, and blood pressure were not statistically significant. Administration of CPJ caused significant reduction in serum interleukin-6 (IL-6) (P < 0.05), but tumor necrosis factor-α (TNF-α) and high-sensitivity C-reactive protein (hs-CRP) remained unchanged during the study. The mean value of serum total antioxidant capacity (TAC) was substantially increased (~ 75%) from 381.88 ± 114.4 at baseline to 1501 ± 817 after 4 weeks of CPJ consumption.

CONCLUSIONS

Consumption of CPJ (50 g/day) appears to have favorable effects on some markers of subclinical inflammation, and to increase plasma concentrations of antioxidants in patients with type 2 diabetes.

Low High-Density Lipoprotein and Risk of Myocardial Infarction

Low HDL is an independent risk factor for myocardial infarction. This paper reviews our current understanding of HDL, HDL structure and function, HDL subclasses, the relationship of low HDL with myocardial infarction, HDL targeted therapy, and clinical trials and studies. Furthermore potential new agents, such as alirocumab (praluent) and evolocumab (repatha) are discussed.

Systematic literature review and meta-analysis of dual therapy with fenofibrate or fenofibric acid and a statin versus a double or equivalent dose of statin monotherapy

OBJECTIVE

To assess the efficacy of fenofibrate and statin dual therapy versus a double or equivalent dose of statin monotherapy.

METHODS

A systematic literature search and meta-analysis was performed for publications before 1 January 2014 in MEDLINE, Embase, and BIOSIS Previews, among others.

RESULTS

The difference in percentage change from baseline was in favor of dual therapy versus a double dose of statin monotherapy for triglycerides (difference -20%; standard error [SE] 2.6%) and HDL-C (8.7%; SE 1.2%), but not for LDL-C (8.4%; SE 1.5%), non-HDL-C (2.8%; SE 1.1%), total cholesterol (4.5%; SE 1.0%) and apolipoprotein B (2.6%; SE 1.1%). For high intensity statins, the difference in percentage change from baseline was in favor of dual therapy versus equivalent statin monotherapy for triglycerides (-17%; SE 2.6%) and for HDL-C (8.7%; SE 1.9%). The difference in percentage change from baseline for LDL-C was 6% (SE 1.7%), implying a greater reduction in LDL-C with statin monotherapy. For moderate intensity statins, the difference in percentage change from baseline was in favor of dual therapy versus equivalent statin monotherapy for triglycerides (-24.2%; SE 1.2%) and HDL-C (8.2%; SE 0.9%). LDL-C decreased 2.2% (SE 1.4%) more with dual therapy.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

When aiming to change HDL-C or triglycerides, dual therapy is to be preferred to doubling the statin dose; conversely, doubling the statin dose is to be preferred when aiming to reduce LDL-C. If the aim is both to change HDL-C or triglycerides and to reduce LDL-C, the importance of the three outcomes may need to be weighed depending on the intensity of the statin. Combining high intensity statin therapy with fenofibrate improves the effect on HDL-C and triglycerides, but lowers the effect on LDL-C. Combining a moderate intensity statin with fenofibrate improves the effect on HDL-C and triglycerides without reducing the effect on LDL-C. There is a need for long-term randomized clinical trials to compare dual therapy versus doubling the statin dose to assess the importance of improvement in HDL-C and triglycerides versus improvement in LDL-C in terms of cardiovascular outcomes. Further, the addition of ezetimibe to statin/fenofibrate therapy may be of interest.

Cholesterol and cognitive performance among community volunteers from the Czech Republic

BACKGROUND

Research shows that lipid levels may be associated with cognitive function, particularly among women. We aimed to examine total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), high-density lipoprotein (HDL), and HDL/LDL ratio in relation to cognitive performance, measured with six well-established cognitive domains and a composite cognitive score (CCS).

METHODS

In this cross-sectional study, biomarkers and neuropsychological assessment were available for 141 adults with MMSE scores ≥ 24 (mean age = 69 years, 47% female, mean education = 14.4 years) attending a neuropsychological evaluation. Ordinary least squares regressions were adjusted for age, gender, education, and depressive symptoms in Model 1 and also for apolipoprotein E4 (APOE4) status in Model 2.

RESULTS

High-density lipoprotein cholesterol (HDL-C) was associated with better CCS (β = 0.24; p = 0.014). This association was significant among women (β = 0.30; p = 0.026) and not among men (β = 0.20; p = 0.124). HDL-C was also related to attention/working memory (β = 0.24; p = 0.021), again only among women (β = 0.37; p = 0.012) and not men (β = 0.15; p = 0.271). Adjusting for APOE4 yielded significance for high HDL-C and CCS (β = 0.24; p = 0.022).

CONCLUSIONS

HDL-C was the main lipoprotein affecting cognitive function, with results somewhat more pronounced among women. Research should investigate the possibility of finding ways to boost HDL-C levels to potentially promote cognitive function.

Dietary fat and carbohydrate modulate the effect of the ATP-binding cassette A1 (ABCA1) R230C variant on metabolic risk parameters in premenopausal women from the Genetics of Atherosclerotic Disease (GEA) Study

Background

Although the R230C-ATP-binding cassette A1 (ABCA1) variant has been consistently associated with HDL-C levels, its association with diabetes and other metabolic parameters is unclear. Estrogen and dietary factors are known to regulate ABCA1 expression in different tissues. Thus, we aimed to explore whether gender, menopausal status and macronutrient proportions of diet modulate the effect of this variant on various metabolic parameters.

Methods

One thousand five hundred ninety-eight controls from the GEA study were included (787 men, 363 premenopausal women and 448 menopausal women), previously assessed for anthropometric and biochemical measurements and visceral to subcutaneous abdominal fat (VAT/SAT) ratio on computed tomography. Taqman assays were performed for genotyping. Diet macronutrient proportions were assessed using a food frequency questionnaire validated for the Mexican population. Multivariate regression models were constructed to assess the interaction between the proportion of dietary macronutrients and the R230C polymorphism on metabolic parameters.

Results

All significant interactions were observed in premenopausal women. Those carrying the risk allele and consuming higher carbohydrate/lower fat diets showed an unfavorable metabolic pattern [lower HDL-C and adiponectin levels, higher VAT/SAT ratio, homeostasis model assessment for insulin resistance (HOMA-IR) and higher gamma-glutamyl transpeptidase (GGT) and alkaline phosphatase (ALP) levels]. Conversely, premenopausal women carrying the risk allele and consuming lower carbohydrate/higher fat diets showed a more favorable metabolic pattern (higher HDL-C and adiponectin levels, and lower VAT/SAT ratio, HOMA-IR, GGT and ALP levels).

Conclusion

This is the first study reporting a gender-specific interaction between ABCA1/R230C variant and dietary carbohydrate and fat percentages affecting VAT/SAT ratio, GGT, ALP, adiponectin levels and HOMA index. Our study confirmed the previously reported gender-specific ABCA1-diet interaction affecting HDL-C levels observed in an independent study. Our results show how gene-environment interactions may help further understand how certain gene variants confer metabolic risk, and may provide information useful to design diet intervention studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12986-015-0040-3) contains supplementary material, which is available to authorized users.

Food insecurity and dyslipidemia in a representative population-based sample in the US

OBJECTIVE

The association of food insecurity with dyslipidemia has not been firmly established. The main objective of this study was to assess whether food insecurity was associated with dyslipidemia.

METHOD

A population-based sample of 1,663 adults from the 2008-2011 Survey of the Health of Wisconsin was used. Food insecurity was defined as an affirmative response to either of the questions: (1) "In the last 12months, have you been concerned about having enough food for you or your family?" (2) "In the last 12months, have your food choices been limited because there wasn't enough money?" High total cholesterol was defined as total cholesterol (TC) >240mg/dL or taking prescribed lipid-lowering medication. Low high-density lipoprotein cholesterol (HDL-C) was defined as <40mg/dL in men and <50mg/dL in women.

RESULTS

Food insecurity was not associated with high TC either among men or women. Food insecurity was associated with a higher likelihood of low HDL-C among women (adjusted odds ratio [AOR]: 2.31 {95% confidence interval [CI]: 1.42, 3.76}), but not among men. Obesity appears to be a partial mediator of the association among women (P from the Sobel test=0.01).

CONCLUSION

These findings suggest that food insecurity may contribute to an increased risk of low HDL-C in women.

Effects of home-based bench step exercise on inflammatory cytokines and lipid profiles in elderly Japanese females: A randomized controlled trial

PURPOSE

The purpose of the current study was to investigate the effects of a 12-week home-based bench step exercise program on inflammatory cytokines and lipid profiles in elderly females.

METHODS

Sixty-two postmenopausal females (65-85 years of age) were randomized to either the bench step exercise group (n=31) or the control group (n=31). The subjects in the bench step exercise group were instructed to perform bench step exercises at the exercise intensity corresponding to lactate threshold (LT), three times per day 10-20 min each session, for a goal of ≥140 min/week at home for 12 weeks. At baseline and 12 weeks, circulating levels of nine inflammatory cytokines (high-molecular-weight adiponectin, interleukin-4 [IL-4], IL-5, IL-6, IL-8, IL-15, tumor necrosis factor-α [TNF-α], TNF-β and interferon-γ [IFN-γ]) and serum lipids including high-density lipoprotein cholesterol (HDL-C) were measured.

RESULTS

The bench step training at the LT significantly increased HDL-C levels and decreased IFN-γ concentrations in the subjects with lower (< 63 mg/dL) baseline HDL-C levels (p<0.05). The change in IFN-γ inversely correlated with the change in HDL-C in the exercise group (ρ=-0.56, p<0.01), whereas this association was not observed in the control group. Additionally, principal component analysis-derived index of what we called "inflammatory status factor" was inversely associated with the changes in HDL-C in the exercise group.

CONCLUSION

The bench step exercise-induced reduction in the IFN-γ levels may partially explain the degree of improvement in the HDL-C levels with the exercise program.

The serum lipid profiles of amyotrophic lateral sclerosis patients: A study from south-west China and a meta-analysis

Associations between the fasting levels of serum lipid and amyotrophic lateral sclerosis (ALS) in Chinese populations remain largely unknown. Our objective was to analyse data from a cohort of ALS patients to determine these associations. Four hundred and thirteen ALS patients and 400 age- and gender-matched healthy controls were included. Fasting serum lipid concentration of all subjects, including total cholesterol, low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C) and triglyceride (TG), were measured at the time of first visit. The revised ALS Functional Rating Scale (ALSFRS-R) was used to assess the severity of ALS. Systems Analysis by Review Manager 5 was used to evaluate differences in dyslipidaemia between ALS patients and controls. Results showed that ALS patients with higher triglyceride levels had longer survival time compared to patients with lower triglyceride levels (p < 0.05). We found a median prolonged life expectancy of 5.8 months for patients with serum triglyceride levels above the median of 127.5 mg/dl. Cox regression analysis indicated that disease duration and age were positively correlated with death, and triglyceride was positively correlated with survival. A meta-analysis indicated that there were no significant differences in mean total cholesterol, TG, LDL or the LDL/HDL ratio between patients and controls. In conclusion, high serum TG might be a protective factor for the survival of patients with ALS.

Mitochondrial DNAs decreased and correlated with clinical features in HCV patients from Yunnan, China

Hepatitis C was the most popular chronic infectious liver disease worldwide. It was identified that Hepatitis C virus (HCV) infection could lead to mitochondrial dysfunction, though the mechanism was not fully understood. To investigate whether mtDNA copy number could be affected by HCV infection and be associated with clinical features of HCV patients, mtDNA copy numbers were analyzed in 242 patients with HCV infection and 226 matched control samples. The results suggested that mtDNA copy numbers significantly decreased in HCV patients (68.80 ± 3.33) than in control samples (81.54 ± 4.50) (p = 0.022). When males/females were separated from total patients to compare mtDNA copy numbers with gender matched controls, mtDNA copy numbers still significantly decreased in male HCV patients (p = 0.002). Further analysis indicated that level of high-density lipoprotein cholesterol (HDL-C) was negatively correlated with mtDNA copy numbers in total HCV patients (r = -0.128, p = 0.047), and this correlation was more significant in male HCV patients (r = -0.266, p = 0.030). Intriguingly, aspartate amino-transferase (AST) showed positive correlation with mtDNA copy numbers (r = 0.260, p = 0.034) in male HCV patients. Our results indicated that mtDNA copy numbers depleted and correlated with clinical features in male HCV patients.

PON1 polymorphisms are predictors of ability to attain HDL-C goals in statin-treated patients

OBJECTIVES

PON1 plays an important role in inhibiting LDL-C oxidation, which reduces atherosclerosis and cardiovascular disease. Elevated PON1 activity or levels may contribute to increased HDL-C levels, but controversy exists over the hypothesis that genetic variation in the PON1 gene locus modulates HDL-C levels and responses to statin treatment. Therefore, the objective of this study was to investigate the association between two polymorphisms in the PON1 gene and statin responses in a south Brazilian population.

DESIGN AND METHODS

The study population included 433 dyslipidemic patients who were prescribed statins. Total cholesterol, triglyceride, HDL-C and LDL-C levels were measured in these patients both before and after approximately 6months of treatment with simvastatin/atorvastatin. Genotypes were assessed by real-time PCR for two PON1 polymorphisms, Q192R (rs662) and L55M (rs854560).

RESULTS

Baseline lipid levels were not associated with Q192R or L55M polymorphisms. For the Q192R (rs662) polymorphism, we observed that HDL-C goals were attained less often in patients with RR homozygosity than in Q allele carriers (χ(2) P=0.009, adjusted residual analysis P=0.003). For the L55M (rs854560) polymorphism, LL homozygotes were underrepresented among subjects that achieved the HDL-C goal (χ(2) P=0.026, adjusted residual analysis P=0.008). Analysis by univariate logistic regression confirmed that QQ/QR and MM/ML carriers had an increased chance of attaining HDL-C goals (OR=2.41, CI95%=1.32-4.40, P=0.004 and OR=1.68, CI95%=1.15-2.45, P=0.008). In a multivariate logistic analysis used to assess predictors of attaining an HDL-C goal>1.55mmol/L, we observed that gender (OR=1.71, CI95%=1.04-2.83, P=0.036), baseline HDL-C levels (OR=1.13, CI95%=1.10-1.16, P<0.001) and the QQ/QR+MM/ML genotypes increased the chance of achieving HDL-C goals (OR=2.81, CI95%=1.35-5.85, P=0.006).

CONCLUSIONS

The results of this study show that the Q192R (rs662) and L55M (rs854560) polymorphisms may play a role in interindividual variation in achievement of HDL-C goals in response to statins.

The effects of electronic medical record phenotyping details on genetic association studies: HDL-C as a case study

Background

Biorepositories linked to de-identified electronic medical records (EMRs) have the potential to complement traditional epidemiologic studies in genotype-phenotype studies of complex human diseases and traits. A major challenge in meeting this potential is the use of EMR-derived data to extract phenotypes and covariates for genetic association studies. Unlike traditional epidemiologic data, EMR-derived data are collected for clinical care and are therefore highly variable across patients. The variability of clinical data coupled with the challenges associated with searching unstructured clinical notes requires the development of algorithms to extract phenotypes for analysis. Given the number of possible algorithms that could be developed for any one EMR-derived phenotype, we explored here the impact algorithm decision logic has on genetic association study results for a single quantitative trait, high density lipoprotein cholesterol (HDL-C).

Results

We used five different algorithms to extract HDL-C from African American subjects genotyped on the Illumina Metabochip (n = 11,519) as part of Epidemiologic Architecture for Genes Linked to Environment (EAGLE). Tests of association between HDL-C and genetic risk scores for HDL-C associated variants suggest that the genetic effect size does not vary substantially across the five HDL-C definitions.

Conclusions

These data collectively suggest that, at least for this quantitative trait, algorithm decision logic and phenotyping details do not appreciably impact genetic association study test statistics.

Therapeutic ultrasound: Increased HDL-Cholesterol following infusions of acoustic microspheres and apolipoprotein A-I plasmids

BACKGROUND

Low levels of HDL-C are an independent cardiovascular risk factor associated with increased premature cardiovascular death. However, HDL-C therapies historically have been limited by issues relating to immunogenicity, hepatotoxicity and scalability, and have been ineffective in clinical trials.

OBJECTIVE

We examined the feasibility of using injectable acoustic microspheres to locally deliver human ApoA-I DNA plasmids in a pre-clinical model and quantify increased production of HDL-C in vivo.

METHODS

Our novel site-specific gene delivery system was examined in naïve rat model and comprised the following steps: (1) intravenous co-administration of a solution containing acoustically active microspheres (Optison™, GE Healthcare, Princeton, New Jersey) and human ApoA-I plasmids; (2) ultrasound verification of the presence of the microspheres within the liver vasculature; (3) External application of locally-directed acoustic energy, (4) induction of microsphere disruption and in situ sonoporation; (4) ApoA-I plasmid hepatic uptake; (5) transcription and expression of human ApoA-I protein; and (6) elevation of serum HDL-C.

RESULTS

Co-administration of ApoA-I plasmids and acoustic microspheres, activated by external ultrasound energy, resulted in transcription and production of human ApoA-I protein and elevated serum HDL-C in rats (up to 61%; p-value < 0.05).

CONCLUSIONS

HDL-C was increased in rats following ultrasound directed delivery of human ApoA-I plasmids by microsphere sonoporation. The present method provides a novel approach to promote ApoA-I synthesis and nascent HDL-C elevation, potentially permitting the use of a minimally-invasive ultrasound-based, gene delivery system for treating individuals with low HDL-C.

PCSK9, apolipoprotein E and lipoviral particles in chronic hepatitis C genotype 3: evidence for genotype-specific regulation of lipoprotein metabolism

BACKGROUND & AIMS

Hepatitis C virus (HCV) associates with lipoproteins to form "lipoviral particles" (LVPs) that can facilitate viral entry into hepatocytes. Initial attachment occurs via heparan sulphate proteoglycans and low-density lipoprotein receptor (LDLR); CD81 then mediates a post-attachment event. Proprotein convertase subtilisin kexin type 9 (PCSK9) enhances the degradation of the LDLR and modulates liver CD81 levels. We measured LVP and PCSK9 in patients chronically infected with HCV genotype (G)3. PCSK9 concentrations were also measured in HCV-G1 to indirectly examine the role of LDLR in LVP clearance.

METHODS

HCV RNA, LVP (d<1.07g/ml) and non-LVP (d>1.07g/ml) fractions, were quantified in patients with HCV-G3 (n=39) by real time RT-PCR and LVP ratios (LVPr; LVP/(LVP+non-LVP)) were calculated. Insulin resistance (IR) was assessed using the homeostasis model assessment of IR (HOMA-IR). Plasma PCSK9 concentrations were measured by ELISA in HCV-G3 and HCV-G1 (n=51).

RESULTS

In HCV-G3 LVP load correlated inversely with HDL-C (r=-0.421; p=0.008), and apoE (r=-0.428; p=0.013). The LVPr varied more than 35-fold (median 0.286; range 0.027 to 0.969); PCSK9 was the strongest negative predictor of LVPr (R(2)=16.2%; p=0.012). HOMA-IR was not associated with LVP load or LVPr. PCSK9 concentrations were significantly lower in HCV-G3 compared to HCV-G1 (p<0.001). PCSK9 did not correlate with LDL-C in HCV-G3 or G1.

CONCLUSIONS

The inverse correlation of LVP with apoE in HCV-G3, compared to the reverse in HCV-G1 suggests HCV genotype-specific differences in apoE mediated viral entry. Lower PCSK9 and LDL concentrations imply upregulated LDLR activity in HCV-G3.

HDL particle subpopulations: Focus on biological function

Low levels of high-density lipoprotein-cholesterol (HDL-C) constitute an independent biomarker of cardiovascular morbi-mortality. However, recent advances have drastically modified the classical and limited view of HDL as a carrier of 'good cholesterol', and have revealed unexpected levels of complexity in the circulating HDL particle pool. HDL particles are indeed highly heterogeneous in structure, intravascular metabolism and biological activity. This review describes recent progress in our understanding of HDL subpopulations and their biological activities, and focuses on relationships between the structural, compositional and functional heterogeneity of HDL particles.

HDL-C levels modify the association between C-reactive protein and coronary artery calcium score

BACKGROUNDS AND AIMS

C-reactive protein (CRP) levels predict incident and recurrent cardiovascular disease (CVD) events; however, associations between CRP and pre-clinical atherosclerosis is less certain. Since high concentrations of high-density lipoprotein cholesterol (HDL-C) are inversely associated with CVD risk, we investigated whether HDL-C modified the association between CRP concentration and measures of preclinical atherosclerosis.

METHODS AND RESULTS

Data were analyzed from a Korean occupational cohort of 12,030 male subjects who underwent a cardiac computed tomography (CT) estimation of coronary artery calcification (CAC) score and an assessment of CVD risk factors. Logistic regression was used to describe associations between CRP and measures of pre-clinical atherosclerosis, such as CAC scores >0. As many as 1351 (11.2%) participants had a CAC score>0. CRP was stratified into 3 groups based on clinical category: <1 mg/L, 1 to <2 mg/L, and ≥ 2 mg/dL. In the bottom CRP group, 907/8697 (10.4%) of subjects had a CAC score >0, compared with 242/1943 (12.5%) in the middle group and 202/1396 (14.5%) in the top CRP group (p < 0.0001). After adjustment for multiple CVD risk factors, there was a positive association between CRP and CAC score>0 (OR between top and bottom CRP groups, 1.41 [1.04, 1.90], p = 0.027) in the lowest HDL-C quartile but not in the highest HDL-C (OR between top and bottom CRP group, 0.80 [0.46, 1.39], p = 0.425).

CONCLUSION

The association between CRP concentration and CAC score differed according to HDL-C levels.

Evaluation of Effect of Antiepileptic Drugs on Serum Lipid Profile among Young Adults with Epilepsy in a Tertiary Care Hospital in Pondicherry

INTRODUCTION

Several studies have reported that commonly used antiepileptic drugs like phenytoin, and carbamazepine increase serum High Density Lipoproteins Cholesterol (HDL-C) levels, while some others documented no such effect. Further, some researchers also observed that valproic acid and other newer antiepileptic drugs like lamotrigine and levetiracetam has no influence on serum lipid profile. The present study was planned to assess and compare serum lipid profile of young adult patients on commonly used antiepileptic drugs (phenytoin, oxcarbazepine and valproic acid) and newer antiepileptic drug (levetiracetam) attending Neurology OPD of a tertiary care hospital in Puducherry, India compared to normal subjects.

MATERIALS AND METHODS

A prospective hospital based cross-sectional study was conducted in Tertiary care hospital. Epileptic patients attending Department of Neurology and taking antiepileptic drugs for last six months or more and on regular follow up; approximately 60 patients on commonly used antiepileptic drugs (20 on phenytoin, 20 on oxcarbazepine, 20 on valproic Acid) and 20 patients on newer antiepileptic drug (levetiracetam) was included in the study. Age and sex matching 80 controls were taken.

STATISTICAL ANALYSIS

Descriptive statistics explained using mean ± SD. Inferential statistics was used depending on the nature of variables. We used one-way-ANOVA and followed by independent t-test for comparison with control group and statistically significant was considered at p-value <0.05.

RESULTS

We observed statistically significant high mean TC, HDL-C, LDL-C and TG levels in the group receiving phenytoin for more than six months when compared with control group. We observed statistically significant high mean TC, HDL-C and TG levels in the group receiving oxcarbazepine for more than six months when compared with control. However, no significant difference was observed in mean LDL-C levels when compared to control. We did not observe any statistically significant difference among mean TC, HDL-C, LDL-C and TG levels in the group receiving valproate. We did not observe any statistically significant difference among mean TC, HDL-C, LDL-C and TG levels in the group receiving levetiracetam.

CONCLUSION

From the present study we can conclude that CYP enzyme inducer anti epileptic medicines like phenytoin and oxcarbazepine is strongly associated with increased levels of TC, LDL-C, HDL-C and TG where as valproate and levetiracetam showed no significant change. Therefore, the serum cholesterol level should be regularly monitored in patients undergoing therapy with inducer anti epileptic medicines.

Prevalence of conventional risk factors and lipid profiles in patients with acute coronary syndrome and significant coronary disease

BACKGROUND

Among patients with coronary artery disease (CAD), 80%-90% present at least one conventional risk factor. On the other hand, lipid profile modification after a cardiovascular event related to acute coronary syndrome (ACS) has been recognized. The prevalence of conventional risk factors and the lipid profile at the time of admission in patients with ACS and significant CAD (stenosis ≥50%) determined through coronary angiography is not well described.

METHODS

We studied 3,447 patients with a diagnosis of ACS and significant CAD with stenosis ≥50%, as shown o n angiography. We recorded the presence of conventional risk factors, including smoking, hypertension, dyslipidemia, and diabetes. In addition, we analyzed the lipid profiles within the first 24 hours of admission. We analyzed the studied population and compared findings according to sex.

RESULTS

Most patients (81.7%) were male. ST-elevation myocardial infarction was present in 51.3% of patients, and non-ST-elevation acute coronary syndrome was present in 48.7%. The most frequent risk factor was smoking, which was present in 68% of patients, followed by hypertension (57.8%), dyslipidemia (47.5%), and diabetes (37.7%). In women, the most frequent risk factors were hypertension, diabetes, and dyslipidemia, whereas in men, smoking was the most frequent. We identified at least one risk factor in 95.7% of all patients, two or three risk factors in 62%, and four risk factors in 8.6% of patients. The lipid profile analysis revealed that 85.1% of patients had some type of dyslipidemia, and the most frequent was low levels of high-density lipoprotein cholesterol (68.6% of cases).

CONCLUSION

We found at least one conventional risk factor in 95.7% of patients with ACS and significant CAD. The lipid profile analysis revealed that two thirds of cases had low high-density lipoprotein cholesterol levels.

Association between triglyceride and high-density lipoprotein cholesterol change following fibrate therapy

BACKGROUND

Debate surrounding the role of fibrates has followed mixed outcomes from several randomised controlled trials. Subgroup analysis of even the negative trials reveals significant reduction in cardiovascular risk amongst patients with low HDL-C and high TG. We previously described factors associated with HDL-C change following fibrates. As fibrates influence both HDL-C and TG levels via their action on PPAR-α, we now wished to study TG change following fibrate therapy and any associations with baseline and change in HDL-C and TC levels.

METHODS

Data was collected from case notes of patients started on fibrates (n=248) between 2002 and 2008 in the lipid clinics at Heart of England NHS Foundation Trust. Regression analyses were carried out to determine factors associated with changes in TG.

RESULTS

Multiple regression analysis revealed that TG change was associated with pre-treatment TG (p<0.001) and TC levels (p=0.029). The association between TG change and pre-treatment TG remained significant when all factors including gender, concurrent statin treatment, diabetes and baseline HDL-C were entered into the regression model. Our previous study demonstrated significant post-fibrate HDL-C change in the group with baseline HDL-C values <1.0mmol/l. In our present study significant TG reduction was observed regardless of the baseline patient characteristics including HDL-C levels.

CONCLUSIONS

The actions of fibrates are considered to be mediated via PPAR-α, but our data suggest that the effects on TG and HDL-C are different. Thus, the mechanisms mediating the changes of these lipids following fibrate treatment may vary.

Effects of dietary components on high-density lipoprotein measures in a cohort of 1,566 participants

Background

Recent data suggest that an increased level of high-density lipoprotein cholesterol (HDL-C) is not causally protective against heart disease, shifting focus to other sub-phenotypes of HDL. Prior work on the effects of dietary intakes has focused largely on HDL-C. The goal of this study was to identify the dietary intakes that affect HDL-related measures: HDL-C, HDL-2, HDL-3, and apoA1 using data from a carotid artery disease case–control cohort.

Methods

A subset of 1,566 participants with extensive lipid phenotype data completed the Harvard Standardized Food Frequency Questionnaire to determine their daily micronutrient intake over the past year. Stepwise linear regression was used to separately evaluate the effects of dietary covariates on adjusted levels of HDL-C, HDL-2, HDL-3, and apoA1.

Results

Dietary folate intake was positively associated with HDL-C (p = 0.007), HDL-2 (p = 0.0011), HDL-3 (p = 0.0022), and apoA1 (p = 0.001). Alcohol intake and myristic acid (14:0), a saturated fat, were each significantly associated with increased levels of all HDL-related measures studied. Dietary carbohydrate and iron intake were significantly associated with decreased levels of all HDL-related measures. Magnesium intake was positively associated with HDL-C, HDL-2, and HDL-3 levels, but not apoA1 levels, while vitamin C was only associated with apoA1 levels. Dietary fiber and protein intake were both associated with HDL-3 levels alone.

Conclusions

This study is the first to report that dietary folate intake is associated with HDL-C, HDL-2, HDL-3, and apoA1 levels in humans. We further identify numerous dietary intake associations with apoA1, HDL-2, and HDL-3 levels. Given the shifting focus away from HDL-C, these data will prove valuable for future epidemiologic investigation of the role of diet and multiple HDL phenotypes in heart disease.

Atheroprotective potentials of curcuminoids against ginger extract in hypercholesterolaemic rabbits

The anti-atherogenic potentials of total ginger (Zingiber officinale) extract (TGE) or curcuminoids extracted from turmeric (Curcuma longa), members of family Zingiberaceae, were compared in hypercholesterolaemia. Rabbits were fed either normal or atherogenic diet. The rabbits on atherogenic diet received treatments with TGE or curcumenoids and placebo concurrently for 6 weeks (n = 6). The anti-atherogenic effects of curcuminoids and ginger are mediated via multiple mechanisms. This effect was correlated with their ability to lower cholesteryl ester transfer protein activity. Ginger extract exerted preferential effects on plasma lipids, reverse cholesterol transport, cholesterol synthesis and inflammatory status. Curcuminoids, however, showed superior antioxidant activity.