Implication of low HDL-c levels in patients with average LDL-c levels: a focus on oxidized LDL, large HDL subpopulation, and adiponectin

Childhood sexual abuse and cholesterol risk: Testing body mass index as a mediator across gender in a national sample of adults

BACKGROUND

Childhood sexual abuse (CSA) is associated with health problems, including cardiometabolic outcomes. Findings directly linking CSA to cholesterol levels are mixed, and identifying mediating pathways is the next logical step. Body mass index (BMI) is one possible mediator, given its association with both CSA and cardiometabolic outcomes. Gendered effects of CSA indicates that BMI may operate differently in men and women.

OBJECTIVE

We tested BMI as a mediator linking CSA to high-density lipoprotein (HDL) and low-density lipoprotein (LDL) using a multiple group structural equation model stratified across gender to test the indirect effects.

PARTICIPANTS AND SETTING

We utilized a sample of 1054 adults (54.7 % women) from the study of Midlife Development in the United States, who were drawn from the general population.

METHODS

Using two waves of data, participants responded to a questionnaire assessing CSA, provided measurements from which to calculate BMI, and a fasting blood sample from which cholesterol levels were measured.

RESULTS

The indirect effects in the overall sample yielded a significant effect from CSA to HDL via BMI (β = -0.03, 95 % CI [-0.050, -0.010]), but not LDL (β = 0.006, 95 % CI [-0.002, 0.014]). The indirect effect from CSA to HDL cholesterol was significant among women (β = -0.04, 95 % CI [-0.066, -0.012]) only. Indirect effects to LDL among both genders were both non-significant.

CONCLUSIONS

BMI appears to be a possible mediator linking CSA to lower HDL cholesterol among women suggesting BMI could be a point of trauma-informed prevention and intervention especially impactful.

Serum lipids concentration on prognosis of high-grade glioma

OBJECTIVE

To investigate the effect of serum lipids concentration on the prognosis of high-grade glioma patients undergoing postoperative radiotherapy.

METHODS

Retrospective analysis of the patients with high-grade glioma who received postoperative Intensity Modulated Radiotherapy between 13 May 2013 and 12 September 2018 was performed. The patients were grouped according to the average values of serum total cholesterol, LDL, and HDL concentration in peripheral blood (before surgery, 6 months after therapy). Cox proportional hazards model was performed to determine whether the total cholesterol concentration, LDL concentration, and HDL concentration in peripheral blood before therapy and their changes after therapy were factors influencing the prognosis.

RESULTS

The results of COX regression analysis showed that the independent prognostic factors of high-grade glioma patients were pathological grade, the extent of resection, serum cholesterol concentration pre-surgery, and the change of LDL concentration from pre-surgery to post-therapy. The prognosis of patients with high serum total cholesterol concentration before therapy was worse than those of patients with low total cholesterol concentration. The 5-year survival rate and the median survival time of patients with high serum total cholesterol concentration before therapy were 4.9% and 23.6 months, but the low cholesterol concentration group were 19.6% and 24.5 months, respectively. Besides, the average serum LDL concentration in high-grade glioma patients gradually increased after therapy. The 5-year survival rate of patients and the median survival time with elevated LDL concentration after therapy is 11.8% and 20.4 months, but the reduced LDL concentration group was 16.7% and 28.4 months, respectively. The total cholesterol and LDL concentration increased significantly after therapy in Grade IV patients while Grade III patients did not.

CONCLUSIONS

The cholesterol concentration before therapy and LDL concentration change from pre-surgery to post-therapy are the factors that affect the prognosis of high-grade glioma patients who have undergone postoperative radiotherapy. In the final analysis, the high serum cholesterol pre-surgery and the increased in serum LDL concentration from pre-surgery to post-therapy were associated with worse survival of patients.

Combined Effect of Omega-3 Fatty Acid and Vitamin D 3 on Oxidized LDL-C and Non-HDL-C Levels in People With Vitamin D Deficiency: A Randomized Controlled Trial

ABSTRACT

The present randomized clinical trial (RCT) was conducted on Jordanian participants with vitamin D deficiency (VDD) with no other medical conditions, to evaluate the combined effect of 1,25-dihydroxy vitamin D 3 (Vit.D 3 ) and omega-3 fatty acid (n-3FA) supplements (D+) on oxidized low-density lipoprotein (Ox-LDL) and non-high-density lipoprotein cholesterol (non-HDL-C) levels as common predictors of cardiovascular diseases (CVDs). Participants were randomized into 4 groups as follows: a control group (C) that received no supplementations, a Vit.D 3 group that received 50,000 IU of Vit.D 3 every week, an n-3FA group that received 300 mg of omega-3 fatty acid every day, and a D+ group that received a combination of both supplements, with the same dosage administered by the previous groups but with a 4-6-hour time interval between Vit.D 3 and n-3FA administration to avoid any possible interaction. All supplementations were administered orally for 8 weeks. Forty-seven participants were allocated to each group. Twenty-six in the control group, 37 participants in the Vit.D 3 group, 37 participants in the n-3FA group, and 46 participants in the D+ group completed the study to the end. The D+ supplementations significantly increased non-HDL-C (118.99 ± 60.98 to 155.26 ± 43.36 mg/dL, P << 0.05) but decreased Ox-LDL-C levels (69.29 ± 37.69 to 52.81 ± 17.30 pg/mL, P = 0.03). The stepwise regression showed that the serum LDL-C level was the main independent variable involved in the elevation of non-HDL levels (R 2 = 0.837) observed at the end of the trial in the D+ group. The groups that were supplemented with either Vit.D 3 alone or n-3FA alone had an insignificant decrease in the level of Ox-LDL-C. In conclusion, despite the observed hyperlipidemic effect, the combination treatment is recommended by the research team because the decrease in Ox-LDL may offset the hyperlipidemic effect.

Diets Rich in Fruits and Vegetables Are Associated with Lower Cardiovascular Disease Risk in Adolescents

Obesity and cardiovascular disease (CVD) risk are public health concerns in adolescents, yet few studies have examined the association of their diet to CVD risk factors. This study investigated associations between diet, body mass index (BMI), waist circumference (WC), blood pressure (BP), and blood lipids in 163 16-17 year olds. Diet recall data were converted into Healthy Eating Index-2010 (HEI) to assess diet quality. Differences in diet between groups with normal or obese BMI, normal or hypertensive BP, and normal or altered lipids were determined. Associations between diet and BMI, WC, BP, and lipids, controlling for race, gender, and socioeconomic status, were examined. Mean HEI was 49.2 (±12.0), with no differences observed between groups. HEI was not associated with any CVD risk. Sweetened beverage consumption was higher in obese adolescents, and positively related to total cholesterol (TC). Fruit intake was negatively related to BMI and diastolic BP. Total vegetable intake was negatively related to systolic BP. Greens and beans were negatively related to TC and LDL. Whole grains were negatively related to HDL. This research suggests a cardioprotective effect of diets rich in fruits and vegetables, as well as low in sweetened beverages in adolescents.

The anti-inflammatory function of HDL is impaired in type 2 diabetes: role of hyperglycemia, paraoxonase-1 and low grade inflammation

BACKGROUND

Functional properties of high density lipoproteins (HDL) are increasingly recognized to play a physiological role in atheroprotection. Type 2 diabetes mellitus (T2DM) is characterized by low HDL cholesterol, but the effect of chronic hyperglycemia on the anti-inflammatory capacity of HDL, a metric of HDL function, is unclear. Therefore, the aim of the present study was to establish the impact of T2DM on the HDL anti-inflammatory capacity, taking paraoxonase-1 (PON-1) activity and low grade inflammation into account.

METHODS

The HDL anti-inflammatory capacity, determined as the ability to suppress tumor necrosis factor-α (TNF-α) induced vascular cell adhesion molecule-1 (VCAM-1) mRNA expression in endothelial cells in vitro (higher values indicate lower anti-inflammatory capacity), PON-1 (arylesterase) activity, hs-C-reactive protein (hs-CRP), serum amyloid A (SAA) and TNF-α were compared in 40 subjects with T2DM (no insulin or statin treatment) and 36 non-diabetic subjects.

RESULTS

T2DM was associated with impaired HDL anti-inflammatory capacity (3.18 vs 1.05 fold increase in VCAM-1 mRNA expression; P < 0.001), coinciding with decreased HDL cholesterol (P = 0.001), apolipoprotein A-I (P = 0.038) and PON-1 activity (P = 0.023), as well as increased hs-CRP (P = 0.043) and TNF-α (P = 0.005). In all subjects combined, age- and sex-adjusted multivariable linear regression analysis demonstrated that impaired HDL anti-inflammatory capacity was associated with hyperglycemia (β = 0.499, P < 0.001), lower PON-1 activity (β = - 0.192, P = 0.030) and higher hs-CRP (β = 0.220, P = 0.016).

CONCLUSIONS

The HDL anti-inflammatory capacity is substantially impaired in T2DM, at least partly attributable to the degree of hyperglycemia, decreased PON-1 activity and enhanced low grade chronic inflammation. Decreased anti-inflammatory protection capacity of HDL conceivably contributes to the increased atherosclerosis risk associated with T2DM.

Association between Vascular Endothelial Markers and Carotid Intima-Media Thickness in Children and Adolescents with Type 1 Diabetes Mellitus

Introduction

Type 1 Diabetes Mellitus (T1DM) is one of the important risk factor for cardiovascular disease. Endothelial dysfunction and increased Carotid Intima-Media Thickness (CIMT) result in cardiovascular complications. Vascular Cell Adhesion Molecule-1 (VCAM-1) and Intercellular Adhesion Molecule-1 (ICAM-1) are two adhesion molecules that are markers of early atherosclerosis and play a significant role in developing atherosclerosis.

Aim

To evaluate CIMT and its association with the levels of ICAM-1 and VCAM-1 in children and adolescents with T1DM.

Materials and Methods

In this descriptive, cross-sectional study conducted between April 2013 and September 2014, 29 children aged 7-20 years with T1DM for at least two years and 29 age and sex-matched, healthy individuals were evaluated. Plasma level of ICAM-1 and VCAM-1 was measured by ELISA, and CIMT via Doppler ultrasound was also assessed. The data were analysed by t-test and Pearson's correlation coefficient in SPSS 16.0 (p≤0.05).

Results

Independent t-test indicated that there is a significant difference in ICAM-1 level between the patients and controls (p<0.001). Further, CIMT was significantly higher in diabetic subject (p<0.001). CIMT was not significantly associated with the level of VCAM-1 and ICAM-1 in the patients (p>0.5).

Conclusion

ICAM-1 and VCAM-1 were not associated with CIMT but, CIMT and level of ICAM-1 were significantly, higher in diabetic patients, and therefore could be used as useful tools for identification of early atherosclerosis in children and adolescents with T1DM.

Association between Six CETP Polymorphisms and Metabolic Syndrome in Uyghur Adults from Xinjiang, China

OBJECTIVE

To explore the association between CETP gene polymorphisms and metabolic syndrome (MS), as well as the relationship between the CETP gene polymorphisms and each component of MS.

METHODS

A total of 571 individuals which were randomly selected from 5692 Uyghur adults were subdivided into two groups, including 280 patients with MS and 291 control subjects, using the group-matching method after matching for gender. We detected CETP polymorphisms (rs5882, rs1800775, rs3764261, rs12149545, rs711752, and rs708272) by using the Snapshot method.

RESULTS

(1) Significant differences were found involving the frequency distribution of genotypes and alleles of rs1800775, rs3764261, rs12149545, rs711752, and rs708272 between the control and MS groups (all p < 0.05). (2) rs1800775, rs3764261, rs12149545, rs711752, and rs708272 polymorphisms were significantly related to the risk of MS (all p < 0.05). (3) The rs1800775 polymorphism was associated with high fasting blood glucose levels and low high density lipoprotein cholesterol (HDL-C); rs3764261 and rs12149545 polymorphisms were associated with all components of MS except high blood pressure; rs711752 and rs708272 polymorphisms were associated with low HDL-C (all p < 0.05). (4) Complete linkage disequilibrium (LD) was identified for two pairs of single nucleotide polymorphisms (SNPs) (rs3764261 and rs12149545 (D' = 1.000, r² = 0.931), rs711752 and rs708272 (D' = 1.000, r² = 0.996)). (5) The A-G-G-G-C (p = 0.013, odds ratio [OR] = 0.622, 95% confidence interval [95% CI] = 0.427-0.906) and A-T-A-A-T (p < 0.001, OR = 0.519, 95% CI = 0.386-0.697) haplotypes were more frequent in the control group than in the case group. Conclusions: The rs1800775, rs3764261, rs12149545, rs711752, and rs708272 polymorphisms of CETP were associated with MS and its components among the Uyghur ethnic group. Complete LD was found between two pairs of SNPs (rs3764261 and rs12149545, rs711752, and rs708272). The A-G-G-G-C and A-T-A-A-T haplotypes might be protective factors for MS.

Polymorphisms FTO rs9939609, PPARG rs1801282 and ADIPOQ rs4632532 and rs182052 but not lifestyle are associated with obesity related-traits in Mexican children

Concerning the genetic factors of obesity, no consistent association between populations has been reported, which may be due to the frequency of polymorphisms, the lifestyle of studied populations and its interaction with other factors. We studied a possible association of polymorphisms FTO rs9939609, PPARG rs1801282, and ADIPOQ rs4632532 and rs182052 with obesity phenotypes in 215 Mexican children. Glucose, triglycerides, cholesterol, HDL and LDL were measured. In addition, weight, height, waist circumference and triceps skin thickness were recorded. High-energy diets and sedentary behavior were evaluated with a validated questionnaire. In contrast with other reports, only FTO rs9939609 was associated with obesity related-traits, including BMI (p = 0.03), waist circumference (p = 0.02), triceps skinfold (p = 0.03) and waist/height ratio (p = 0.01), and also with cholesterol levels (p = 0.02) and LDL (p = 0.009). Lower levels of triglycerides (p=0.04) were related with presence of PPARG rs1801282, while ADIPOQ rs4632532 showed an effect on HDL (p = 0.03) levels. On the other hand, diet, physical activity and screen time were not related with obesity. In summary, only FTO rs9939609 was associated with obesity related-traits, while PPARG2 rs1801282 and ADIPOQ rs4632532 were involved in lipid metabolism.

Associations of Circulating Oxidized LDL and Conventional Biomarkers of Cardiovascular Disease in a Cross-Sectional Study of the Navajo Population

The prevalences of cardiovascular disease (CVD) and type 2 diabetes (T2D) have increased among the Navajo Native American community in recent decades. Oxidized low-density lipoprotein (oxLDL) is a novel CVD biomarker that has never been assessed in the Navajo population. We examined the relationship of oxLDL to conventional CVD and T2D risk factors and biomarkers in a cross-sectional population of Navajo participants. This cross-sectional study included 252 participants from 20 Navajo communities from the Diné Network for Environmental Health Project. Plasma samples were tested for oxLDL levels by a sandwich enzyme-linked immunosorbent assay. Univariate and multivariate analyses were used to determine the relationship of oxLDL and oxidized- to non-oxidized lipoprotein ratios to glycated hemoglobin (HbA1c), C-reactive protein (CRP), interleukin 6 (IL6) and demographic and health variables. Type 2 diabetes, hypertension and obesity are very prevalent in this Navajo population. HbA1c, CRP, body mass index (BMI), high-density lipoprotein, and triglycerides were at levels that may increase risk for CVD and T2D. Median oxLDL level was 47 (36.8–57) U/L. Correlational analysis showed that although oxLDL alone was not associated with HbA1c, oxLDL/HDL, oxLDL/LDL and CRP were significantly associated with HbA1c and glucose. OxLDL, oxLDL/HDL and oxLDL/LDL were significantly associated with CRP. Multivariate analysis showed that triglycerides were a common and strong predictor of oxLDL, oxLDL/HDL and oxLDL/LDL. OxLDL was trended with HbA1c and glucose but did not reach significance, however, HbA1c was an independent predictor of OxLDL/HDL. CRP trended with oxLDL/HDL and was a weak predictor of oxLDL/LDL. This Navajo subset appears to have oxLDL levels comparable to subjects without evidence of CVD reported in other studies. The high prevalence of T2D, hypertension and obesity along with abnormal levels of other biomarkers including HbA1c indicate that the Navajo population has a worsening CVD risk profile.

The improvement of large High-Density Lipoprotein (HDL) particle levels, and presumably HDL metabolism, depend on effects of low-carbohydrate diet and weight loss

Depressed levels of atheroprotective large HDL particles are common in obesity and cardiovascular disease (CVD). Increases in large HDL particles are favourably associated with reduced CVD event risk and coronary plaque burden. The objective of the study is to compare the effectiveness of low-carbohydrate diets and weight loss for increasing blood levels of large HDL particles at 1 year. This study was performed by screening for body mass index (BMI) and metabolic syndrome in 160 consecutive subjects referred to our out-patient Metabolic Unit in South Italy. We administered dietary advice to four small groups rather than individually. A single team comprised of a dietitian and physician administered diet-specific advice to each group. Large HDL particles at baseline and 1 year were measured using two-dimensional gel electrophoresis. Dietary intake was assessed via 3-day diet records. Although 1-year weight loss did not differ between diet groups (mean 4.4 %), increases in large HDL particles paralleled the degree of carbohydrate restriction across the four diets (p<0.001 for trend). Regression analysis indicated that magnitude of carbohydrate restriction (percentage of calories as carbohydrate at 1 year) and weight loss were each independent predictors of 1-year increases in large HDL concentration. Changes in HDL cholesterol concentration were modestly correlated with changes in large HDL particle concentration (r=0.47, p=.001). In conclusion, reduction of excess dietary carbohydrate and body weight improved large HDL levels. Comparison trials with cardiovascular outcomes are needed to more fully evaluate these findings.

Hyperlipidemia-induced hepatic and small intestine ER stress and decreased paraoxonase 1 expression and activity is associated with HDL dysfunction in Syrian hamsters

SCOPE

We aimed at investigating the mechanisms linking hyperlipidemia (HL) with dysfunctional HDL and its main antioxidant enzyme, paraoxonase1 (PON1). PON1 expression and activity was determined in the small intestine, liver, and sera of normal and HL hamsters and associated with the ER stress (ERS) and the development of aortic valve lesions.

METHODS AND RESULTS

Male Golden Syrian hamsters were fed standard chow (N) or standard diet with 3% cholesterol and 15% butter for 16 weeks. All hamsters on fat diet developed HL, 50% also hyperglycemia (HLHG) and a fourfold increased homeostasis model assessment of insuline resistance. PON1 expression was reduced in the small intestine and liver (N > HL > HLHG) along with the increased extent of ERS, oxidized lipids, and decreased expression of liver X receptors beta (LXRβ) in the small intestine, peroxisome proliferator-activated receptor-γ (PPARγ) in the liver, and of the glucose transporter 4 in the myocardium. Serum PON1 levels decreased along with the increase of oxidized LDL and lesion areas of the aortic valves (N > HL > HLHG).

CONCLUSION

The fat diet activates the ERS and oxidative stress, decreases LXRβ, PPARγ, and PON1 in the small intestine, liver, and sera of all HL animals, in parallel with the appearance of atherosclerotic lesions in the aortic valves.

Reducing women's cardiovascular disease risk profile

Heart disease is the leading cause of death in women. Unique risk factors have been recognized, including pre-eclampsia, eclampsia and autoimmune diseases. Diabetes and hypertension (HTN) also play a unique role in women. Women with diabetes have a higher risk for coronary heart disease and microvascular disease compared with males. Additionally, older women have a high prevalence of uncontrolled HTN and women tend to have more treatment resistant HTN, increasing risk for cardiovascular events and mortality. The outcomes of cardiovascular disease have shown an increase in the number of heart attacks in younger women, though there is decreasing mortality. Treatment with coronary artery bypass graft surgery and percutaneous intervention has also shown to have poorer outcomes in women.

Antioxidant and lipid-regulating effects of probucol combined with atorvastatin in patients with acute coronary syndrome

OBJECTIVE

To investigate the effects of probucol combined with atorvastatin on the serum oxidation index and lipid levels in patients diagnosed with acute coronary syndrome (ACS).

METHODS

We randomly assigned 126 ACS patients (77 males and 49 females) to the control group (atorvastatin 20 mg/day, n=62) or the treatment group (atorvastatin 20 mg/day and probucol 750 mg/day, n=64). All the patients were followed up for 12 weeks. As oxidization indices, we measured the serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), oxidized LDL (ox-LDL), and paraoxonase-1 (PON1) before and after treatment. We also monitored the adverse effects of the drugs during the treatment.

RESULTS

At baseline, there were no obvious differences (P>0.05) between the two groups (including age, gender, etc.). After 12 weeks of treatment, the ox-LDL levels in the treatment group were significantly lower while PON1 levels were significantly higher than those in the control group. There were no statistically significant difference between the two groups with respect to the side effects (P<0.05).

CONCLUSIONS

The combined use of atorvastatin and probucol in ACS patients could reduce ox-LDL expression and increase PON1 expression more effectively than use atorvastatin alone.

Low serum high density lipoprotein cholesterol concentration is an independent predictor for enhanced inflammation and endothelial activation

Background

Inflammation, endothelial activation and oxidative stress have been established as key events in the initiation and progression of atherosclerosis. High-density lipoprotein cholesterol (HDL-c) is protective against atherosclerosis and coronary heart disease, but its association with inflammation, endothelial activation and oxidative stress is not well established.

Objectives

(1) To compare the concentrations of biomarkers of inflammation, endothelial activation and oxidative stress in subjects with low HDL-c compared to normal HDL-c; (2) To examine the association and correlation between HDL-c and these biomarkers and (3) To determine whether HDL-c is an independent predictor of these biomarkers.

Methods

422 subjects (mean age±SD = 43.2±11.9years) of whom 207 had low HDL-c concentrations (HDL-c <1.0mmol/L and <1.3mmol/L for males and females respectively) and 215 normal controls (HDL-c ≥1.0 and ≥1.3mmol/L for males and females respectively) were recruited in this study. The groups were matched for age, gender, ethnicity, smoking status, diabetes mellitus and hypertension. Fasting blood samples were collected for analysis of biomarkers of inflammation [high-sensitivity C-reactive protein (hsCRP) and Interleukin-6 (IL-6)], endothelial activation [soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), soluble Intercellular Adhesion Molecule-1 (sICAM-1) and E-selectin)] and oxidative stress [F2-Isoprostanes, oxidized Low Density Lipoprotein (ox-LDL) and Malondialdehyde (MDA)].

Results

Subjects with low HDL-c had greater concentrations of inflammation, endothelial activation and oxidative stress biomarkers compared to controls. There were negative correlations between HDL-c concentration and biomarkers of inflammation (IL-6, p = 0.02), endothelial activation (sVCAM-1 and E-selectin, p = 0.029 and 0.002, respectively), and oxidative stress (MDA and F₂-isoprostane, p = 0.036 and <0.0001, respectively). Multiple linear regression analysis showed HDL-c as an independent predictor of IL-6 (p = 0.02) and sVCAM-1 (p<0.03) after correcting for various confounding factors.

Conclusion

Low serum HDL-c concentration is strongly correlated with enhanced status of inflammation, endothelial activation and oxidative stress. It is also an independent predictor for enhanced inflammation and endothelial activation, which are pivotal in the pathogenesis of atherosclerosis and atherosclerosis-related complications.

Anticipatory role of high density lipoprotein and endothelial dysfunction: an overview

High Density Lipoprotein (HDL) has been witnessed to possess a range of different functions that contribute to its atheroprotective effects. These functions are: the promotion of macrophage cholesterol efflux, reverse cholesterol transport, anti-inflammatory, anti-thrombotic, anti-apoptotic, pro-fibrinolytic and anti-oxidative functions. Paraoxonase 1 (PON1) is an HDL associated enzyme esterase/homocysteinethiolactonase that contributes to the anti-oxidant and anti-atherosclerotic capabilities of HDL. PON1 is directly involved in the etiopathogenesis of atherosclerosis through the modulation of nitric oxide (NO) bioavailability. The aim of this review is to summarize the role of HDL on endothelial homeostasis, and also to describe the recently characterized molecular pathways involved.

Arylesterase activity is associated with antioxidant intake and paraoxonase-1 (PON1) gene methylation in metabolic syndrome patients following an energy restricted diet

The arylesterase (ARE) activity linked to the paraoxonase-1 (PON1) gene is known to protect lipoproteins from oxidation and provide defense against metabolic syndrome (MetS) and cardiovascular diseases. The epigenetic regulation of enzymatic activities is gaining importance nowadays. This research aimed to assess the potential relationships between the ARE activity with the methylation levels of the PON1 gene transcriptional regulatory region, anthropometrics, biochemical markers and antioxidant dietary components. Forty-seven subjects (47 ± 10 y.o; BMI 36.2 ± 3.8 kg/m(2); 46.8 % female) with MetS features, who followed a six-month energy-restricted dietary weight-loss intervention, were included in this study (www.clinicaltrials.gov; NCT01087086). Anthropometric, biochemical, enzymatic and dietary data were assessed using validated procedures. PON1 transcriptional regulatory region methylation was analyzed by a microarray technical approach. Volunteers reduced ARE activity in parallel with body weight (p = 0.005), BMI (p = 0.006), total fat mass (p = 0.020), diastolic blood pressure (p = 0.018), mean blood pressure (p = 0.022) and triglycerides (p = 0.014). Methylation levels of some CpG sites of the PON1 gene correlated negatively with ARE activity (p < 0.05). Interestingly, dietary vitamin C (p = 0.001), tocopherols (p = 0.009) and lycopene (p = 0.038) were positively associated with ARE activity and showed an inverse correlation (p = 0.004, p = 0.029 and p = 0.021, respectively) with the methylation of some selected CpG sites of the PON1 gene. In conclusion, ARE activity decreased in parallel with MetS-related markers associated to the energy restriction, while dietary antioxidants might enhance the ARE activity by lowering the PON1 gene methylation in patients with MetS features.