Background ABCA1 genetic variation is known to play a role in HDL-C levels and various studies have also implicated ABCA1 variation in cardiovascular risk. The functional ABCA1/R230C variant is frequent in the Mexican population and has been consistently associated with low HDL-C concentrations. Although it has been associated with other cardiovascular risk factors such as obesity and type 2 diabetes mellitus, it is not known whether it is associated with coronary artery disease (CAD).AimThe purpose of the study was to analyze whether the ABCA1/R230C variant is associated with premature CAD in a case-control association study (GEA or Genetics of Atherosclerotic Disease), and to explore whether BMI modulates the effect of the C230 allele on other metabolic traits using a population-based design.ResultsThe C230 allele was significantly associated with both lower HDL-C levels and a lower risk of premature CAD as compared to controls (OR = 0.566; Padd = 1.499×10−5). In addition, BMI modulated the effect of R230C on body fat distribution, as the correlation between BMI and visceral to subcutaneous adipose tissue (a metric of the propensity to store fat viscerally as compared to subcutaneously) was negative in RR homozygous individuals, but positive in premenopausal women bearing the C230 allele, with a statistically significant interaction (P = 0.005). BMI-R230C interaction was also significant for triglyceride levels in women regardless of their menopausal status (P = 0.036).ConclusionThis is the first study assessing the effect of the R230C/ABCA1 variant in remature CAD. C230 was associated with both decreased HDL-C levels and a lower risk of premature CAD, and gender-specific BMI-R230C interactions were observed for different metabolic traits. These interactions may help explain inconsistencies in associations, and underscore the need to further analyze interactions of this functional and frequent variant with diet, exercise and other environmental factors.

BackgroundA growing body of evidence suggests that psychological stress is an independent cardiovascular risk factor. Obesity prevalence shows accelerating trends worldwide, and is known to be associated with a range of comorbidities and survival. The aim of this study was to assess the relationship between self-perceived psychological stress with parameters of adiposity, metabolic syndrome, and subclinical atherosclerosis in Mexican participants.MethodsMetabolic Syndrome was defined using the Adult Treatment Panel III criteria, obesity was defined as BMI >30, subclinical atherosclerosis disease was determined by computed tomography, and carotid intima media thickness was determined by ultrasonography. Self-perceived psychological stress was assessed using a single-item questionnaire.ResultsA total of 1243 control subjects were included in the sample, mean age 54.2 ± 9 years old; the prevalence of chronic self-perceived psychological stress (>5 years) was 10.13 %, female gender (62.7 %), obesity prevalence (48.4 %), and self-reporting sedentary lifestyle (56.3 %). The chronic stressed cohort presented higher subcutaneous abdominal fat content (285 vs 319 cm2), and carotid intima media thickness (0.63 vs 0.66 mm; p < 0.01 for both). However, after adjustment for lifestyle/social covariates (Model 1) and biological mediators (Model 2), chronic self-perceived stress was independently associated with obesity in men (OR 2.85, 95 % CI 1.51 – 5.40) and carotid atherosclerosis in women (OR 2.262, 95 % CI 1.47 – 4.67; p < 0.01 for both).ConclusionOur study suggests that self-reported chronic stress is an independent risk factor for obesity in men. In addition, carotid atherosclerosis was also found to be an independent risk factor in women in a Mexican population sample.

BackgroundExperimental studies have shown that high free fatty acid (FFA) and low adiponectin (ADIPO) levels are involved in the mechanisms by which adiposity promotes insulin resistance (IR). However, no previous clinical studies have simultaneously analysed the relative contribution of FFA and ADIPO levels on the relation of abdominal visceral fat (AVF) with insulin resistance.ObjectiveTo analyse the contribution of low ADIPO (adiponectin < =p25th: 8.67 μg/mL in women and 5.30 μg/mL in men), and high FFAs (FFAs > =p75th: 0.745 mEq/L in women and 0.60 mEq/L in men) to the association of high AVF (AVF > =p75th: 127 cm2 in women; 152.7 cm2 in men) with insulin resistance (HOMA-IR > =75th: 3.58 in women and 3.12 in men), in non-diabetic subjects.Material and methodsA cross-sectional analysis was performed including 1217 control participants of the Genetics of Atherosclerotic Disease study (GEA). Clinical, tomographic and biochemical parameters were measured in all participants. Logistic regression models were used to assess the association of high AVF with IR stratifying according to gender, and to normal or low ADIPO and normal or high FFA serum levels.ResultsIn comparison to referent group, in men low ADIPO unlike high FFA increased the risk of IR. Females with normal AVF and low ADIPO, or high AVF and normal ADIPO had aprox 3 folds risk of IR (OR [IC95%]: 3.7 [2.1-6.6], p < 0.001, and 3.4 [2.0-5.7], p < 0.001; respectively). The risk increased to 7.6 [4.2-13.8], p < 0.001 when high AVF and low ADIPO were present. Irrespective of AVF, the effect of low ADIPO on IR was higher than that seen for high FFA. Besides, our results suggest an additive effect of high AVF, high FFA and low ADIPO on the IR prevalence.ConclusionsThe present study provides novel and important information about the combined effect of high AVF and low ADIPO on the risk of IR. Furthermore, our data suggest that the effect of low adiponectin levels on the high AVF-IR association is stronger than that observed for high FFA, suggesting that adiponectin could be used as biomarker to identify subjects at high risk for T2DM and CAD.

Background: The association of subclinical hypothyroidism (SCH) with insulin resistance, metabolic syndrome (MS), and coronary atherosclerosis is uncertain. Objective: To investigate the role of increased intrahepatic fat in the association of SCH with insulin resistance, MS, and coronary atherosclerosis. Design, patients, and methods: We conducted a cross-sectional study in a sample of 753 subjects (46% males) aged 35-70 years with no history of diabetes, renal, hepatic, thyroid, or coronary heart disease, and were participants of the Genetics of Atherosclerotic Disease study. SCH was defined as a high serum TSH level with normal free thyroxine concentration. Fatty liver (FL), coronary artery calcification (CAC), and abdominal visceral adipose tissue were assessed by computed tomography. Cross-sectional associations of SCH with and without FL, with MS, insulin resistance, and subclinical atherosclerosis defined as a CAC score O0, were examined in logistic regression models. Results: SCH was observed in 17.7% of the population studied. The prevalence of FL was similar in both euthyroid and SCH subjects (31.8 vs 27.8%, PZ0.371). SCH plus FL subjects were heavier and had more metabolic abnormalities compared with SCH plus normal liver subjects. In multivariate-adjusted logistic regression analyses, SCH plus FL was associated with MS (odds ratio (OR): 2.73, 95% CI: 1.26-5.92), insulin resistance (OR: 4.91, 95% CI: 1.63-14.75), and CAC score O0 (OR: 3.05, 95% CI: 1.20-7.76). SCH without FL showed no associations. Conclusion: SCH with FL is associated with increased odds of MS, insulin resistance, and CAC, independent of potential confounders.

BackgroundOxidative stress causes biochemical changes in lipids and proteins; these changes can induce damage to the vascular endothelium and create maternal complications that are characteristic of preeclampsia. In this study, we evaluated the oxidative profile of lipoproteins isolated from women with preeclampsia. MethodsThirty women diagnosed with preeclampsia and thirty women without preeclampsia were included in the study. Lipid-damage biomarkers, including conjugated dienes, lipohydroperoxides and malondialdehyde, were measured. The reduction of nitroblue tetrazolium, the formation of dityrosines, and the carbonylation of proteins were assessed as indicators of protein damage. The protective activity of HDL-c was evaluated by the paraoxonase-I activity present on the HDL-c particles. Serum lipid profiles were also quantified in both groups. Data were analysed using Student’s t test and the Pearson correlation coefficient.ResultsOur results demonstrated in PE women evident oxidative changes in the lipids and proteins in HDL-c and LDL-c particles and the activity of the antioxidant enzyme PON-I decreased 59.9%. HDL-c exhibited self-defence, as demonstrated by the negative correlation between paraoxonase-I activity and the formation of lipohydroperoxides in HDL-c (r = −0.3755, p < 0.005).ConclusionsLDL-c and HDL-c isolated from women with preeclampsia show oxidative damage to lipids and proteins. We propose an oxidative profile based on the oxidation levels indicated by each of the markers used. We also found that paraoxonase-I is inactivated in the presence of lipohydroperoxides. Antioxidant support might be helpful to reduce oxidative stress in patients with preeclampsia. Further investigations are necessary to define the association between antioxidant activities and preeclampsia.