Association of single and joint metals with albuminuria and estimated glomerular filtration longitudinal change in middle-aged adults from Spain: The Aragon workers health study

The nephrotoxicity of low-chronic metal exposures is unclear, especially considering several metals simultaneously. We assessed the individual and joint association of metals with longitudinal change in renal endpoints in Aragon Workers Health Study participants with available measures of essential (cobalt [Co], copper [Cu], molybdenum [Mo] and zinc [Zn]) and non-essential (As, barium [Ba], Cd, chromium [Cr], antimony [Sb], titanium [Ti], uranium [U], vanadium [V] and tungsten [W]) urine metals and albumin-to-creatinine ratio (ACR) (N = 707) and estimated glomerular filtration rate (eGFR) (N = 1493) change. Median levels were 0.24, 7.0, 18.6, 295, 3.1, 1.9, 0.28, 1.16, 9.7, 0.66, 0.22 μg/g for Co, Cu, Mo, Zn, As, Ba, Cd, Cr, Sb, Ti, V and W, respectively, and 52.5 and 27.2 ng/g for Sb and U, respectively. In single metal analysis, higher As, Cr and W concentrations were associated with increasing ACR annual change. Higher Zn, As and Cr concentrations were associated with decreasing eGFR annual change. The shape of the longitudinal dose-responses, however, was compatible with a nephrotoxic role for all metals, both in ACR and eGFR models. In joint metal analysis, both higher mixtures of Cu-Zn-As-Ba-Ti-U-V-W and Co-Cd-Cr-Sb-V-W showed associations with increasing ACR and decreasing eGFR annual change. As and Cr were main drivers of the ACR change joint metal association. For the eGFR change joint metal association, while Zn and Cr were main drivers, other metals also contributed substantially. We identified potential interactions for As, Zn and W by other metals with ACR change, but not with eGFR change. Our findings support that Zn, As, Cr and W and suggestively other metals, are nephrotoxic at relatively low exposure levels. Metal exposure reduction and mitigation interventions may improve prevention and decrease the burden of renal disease in the population.

Arsenic exposure and human blood DNA methylation and hydroxymethylation profiles in two diverse populations from Bangladesh and Spain

BACKGROUND

Associations of arsenic (As) with the sum of 5-mC and 5-hmC levels have been reported; however, As exposure-related differences of the separated 5-mC and 5-hmC markers have rarely been studied.

METHODS

In this study, we evaluated the association of arsenic exposure biomarkers and 5-mC and 5-hmC in 30 healthy men (43-55 years) from the Aragon Workers Health Study (AWHS) (Spain) and 31 healthy men (31-50 years) from the Folic Acid and Creatinine Trial (FACT) (Bangladesh). We conducted 5-mC and 5-hmC profiling using Infinium MethylationEPIC arrays, on paired standard and modified (ox-BS in AWHS and TAB in FACT) bisulfite converted blood DNA samples.

RESULTS

The median for the sum of urine inorganic and methylated As species (ΣAs) (μg/L) was 12.5 for AWHS and 89.6 for FACT. The median of blood As (μg/L) was 8.8 for AWHS and 10.2 for FACT. At a statistical significance p-value cut-off of 0.01, the differentially methylated (DMP) and hydroxymethylated (DHP) positions were mostly located in different genomic sites. Several DMPs and DHPs were consistently found in AWHS and FACT both for urine ΣAs and blood models, being of special interest those attributed to the DIP2C gene. Three DMPs (annotated to CLEC12A) for AWHS and one DHP (annotated to NPLOC4) for FACT remained statistically significant after false discovery rate (FDR) correction. Pathways related to chronic diseases including cardiovascular, cancer and neurological were enriched.

CONCLUSIONS

While we identified common 5-hmC and 5-mC signatures in two populations exposed to varying levels of inorganic As, differences in As-related epigenetic sites across the study populations may additionally reflect low and high As-specific associations. This work contributes a deeper understanding of potential epigenetic dysregulations of As. However, further research is needed to confirm biological consequences associated with DIP2C epigenetic regulation and to investigate the role of 5-hmC and 5-mC separately in As-induced health disorders at different exposure levels.

Identification of differentially methylated BRCA1 and CRISP2 DNA regions as blood surrogate markers for cardiovascular disease

Genome-wide Illumina InfiniumMethylation 450 K DNA methylation analysis was performed on blood samples from clinical atherosclerosis patients (n = 8) and healthy donors (n = 8) in the LVAD study (NCT02174133, NCT01799005). Multiple differentially methylated regions (DMR) could be identified in atherosclerosis patients, related to epigenetic control of cell adhesion, chemotaxis, cytoskeletal reorganisations, cell proliferation, cell death, estrogen receptor pathways and phagocytic immune responses. Furthermore, a subset of 34 DMRs related to impaired oxidative stress, DNA repair, and inflammatory pathways could be replicated in an independent cohort study of donor-matched healthy and atherosclerotic human aorta tissue (n = 15) and human carotid plaque samples (n = 19). Upon integrated network analysis, BRCA1 and CRISP2 DMRs were identified as most central disease-associated DNA methylation biomarkers. Differentially methylated BRCA1 and CRISP2 regions were verified by MassARRAY Epityper and pyrosequencing assays and could be further replicated in blood, aorta tissue and carotid plaque material of atherosclerosis patients. Moreover, methylation changes at BRCA1 and CRISP2 specific CpG sites were consistently associated with subclinical atherosclerosis measures (coronary calcium score and carotid intima media thickness) in an independent sample cohort of middle-aged men with subclinical cardiovascular disease in the Aragon Workers’ Health Study (n = 24). Altogether, BRCA1 and CRISP2 DMRs hold promise as novel blood surrogate markers for early risk stratification and CVD prevention.

[Compliance with Physical Activity Recommendations and Associated Factors in a Cohort of Spanish Adult Workers]

BACKGROUND

Physical inactivity remains a public health problem worldwide. The purpose of this study was to determine compliance with physical activity (PA) recommendations developed by the World Health Organization (WHO) and to analyze the association with different cardiovascular risk factors (CVRF) and sociodemographic and lifestyle determinants in a sample of Spanish workers.

METHODS

A cross sectional analysis was carried out in a sample of 2.651 individuals (2.428 men and 133 women, aged 40-55 years old) from the Aragon Workers' Health Study (AWHS). Sample was divided into two groups depending on whether they met PA recommendations during the last year, including transportation, leisure and occupational PA. Sociodemographic, anthropometric, clinical, pharmacological and lifestyle data were collected during the years 2011-2014. Median and interquartile range for quantitative variables and frequency distribution for categorical variables were used. Crude and adjusted binary logistic regression models were carried out to study the likelihood of meeting with PA recommendations based on the number of CVRF (hypertension, dyslipidemia, diabetes, obesity and smoking) present.

RESULTS

47.0% of workers complied with WHO recommendations for PA. Lower prevalence of compliance was found among those participants presenting some CVRF (39.7% in hypertensive, 38.7% in dyslipidemic and 32.7% in diabetic). Of the total study sample, 51.3% reported not performing PA or practice a light PA, 20.2% moderate and 28.5% vigorous or very vigorous PA. The likelihood of compliance with PA recommendations decreased with increasing the number of CVRF: 1 CVRF (OR: 0.62; 95%IC: 0.49-0.78), 2 CVRF (OR: 0.49; 95% IC: 0.38-0.62), 3 CVRF (OR: 0.34; 95% IC: 0.25-0.46), 4 CVRF (OR: 0.19; 95% IC: 0.11-0.32).

CONCLUSIONS

Compliance with recommendations of PA in our population remains insufficient, moreover in those with increased cardiovascular risk.

Apolipoprotein E4 association with metabolic syndrome depends on body fatness

BACKGROUND AND AIMS

The human Apolipoprotein E (APOE) gene is polymorphic. The APOE*4 allele is a risk factor for cardiovascular disease and could contribute to the development of the metabolic syndrome (MetS) as it may affect all MetS components. We hypothesize that the common APOE4 polymorphism differentially regulates MetS risk and that this association might be modulated by body fatness.

METHODS & RESULTS

We used body mass index (BMI) as surrogate of fatness and cross-sectionally studied the prevalence of MetS in 4408 middle-aged men of the Aragon Workers Health Study (AWHS). Our analysis revealed i) a gene dose-dependent association between APOE*4 allele and increased risk for MetS, ii) this association primarily derived from the overweight subjects. For these individuals, the MetS risk was higher in APOE*4 carriers than in non-carriers (Odds Ratio = 1.31; 95% CI, 1.03-1.67). Additionally, we examined 3908 healthy young individuals from the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, followed-up for 25 years. Compared with APOE*4 non-carriers, APOE*4 presence significantly increased the risk of developing MetS (Hazard Ratio, 1.12; 95% CI, 1.00-1.26). Again, an interplay between APOE*4 and the longitudinal development of fatness towards the onset of MetS occurred throughout the study. For individuals with BMI gain below the median, the cumulative onset rate of MetS was significantly higher in APOE*4 carriers than in the non-carriers (HR, 1.29; 95% CI, 1.07-1.55).

CONCLUSIONS

Carrying APOE*4 alleles increases MetS in a dose-dependent manner, characterizing individual's APOE genotype might help identify at-risk subjects for preventive intervention.