Smoking is Associated to DNA Methylation in Atherosclerotic Carotid Lesions

Marten A Siemelink; Sander W van der Laan; Saskia Haitjema; Ian D van Koeverden; Jacco Schaap; Marian Wesseling; Saskia C A de Jager; Michal Mokry; Maarten van Iterson; Koen F Dekkers; René Luijk; Hassan Foroughi Asl; Tom Michoel; Johan L M Björkegren; Einari Aavik; Seppo Ylä-Herttuala; Gert J de Borst; Folkert W Asselbergs; Hamid El Azzouzi; Hester M den Ruijter; Bas T Heijmans; Gerard Pasterkamp

doi:10.1161/CIRCGEN.117.002030

Smoking is Associated to DNA Methylation in Atherosclerotic Carotid Lesions

Circ Genom Precis Med. 2018 Sep;11(9):e002030. doi: 10.1161/CIRCGEN.117.002030.

Authors

Marten A Siemelink¹, Sander W van der Laan¹, Saskia Haitjema², Ian D van Koeverden¹, Jacco Schaap¹, Marian Wesseling¹, Saskia C A de Jager^{1

3}, Michal Mokry⁴, Maarten van Iterson⁵, Koen F Dekkers⁵, René Luijk^{5

6}, Hassan Foroughi Asl⁷, Tom Michoel⁸, Johan L M Björkegren^{7

9}, Einari Aavik¹⁰, Seppo Ylä-Herttuala¹¹, Gert J de Borst¹², Folkert W Asselbergs^{13

14

15

16}, Hamid El Azzouzi, Hester M den Ruijter¹, Bas T Heijmans⁵, Gerard Pasterkamp²

Affiliations

¹ Laboratory of Experimental Cardiology, University Medical Center Utrecht, University of Utrecht, the Netherlands (M.A.S., S.W.v.d.L., I.D.v.K., J.S., M.W., S.C.A.d.J., H.M.d.R.).
² Laboratory of Clinical Chemistry and Hematology, University Medical Center Utrecht, University of Utrecht, the Netherlands (S.H., G.P.).
³ Laboratory of Translational Immunology, University Medical Center Utrecht, University of Utrecht, the Netherlands (S.C.A.d.J.).
⁴ Division Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, University of Utrecht, the Netherlands (M.M.).
⁵ Molecular Epidemiology, Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, 2333 ZC, the Netherlands (M.v.I., K.F.D., R.L., B.T.H.).
⁶ Medical Statistics, Biomedical Data Sciences, Leiden University Medical Center, Leiden, 2333 ZC, the Netherlands (R.L.).
⁷ Cardiovascular Genomics Group, Division of Vascular Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden (H.F.A., J.L.M.B.).
⁸ Division of Genetics and Genomics, The Roslin Institute, The University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, United Kingdom (T.M.).
⁹ Department of Genetics & Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America Integrated Cardio Metabolic Centre, Department of Medicine, Karolinska Institutet, Karolinska Universitetssjukhuset, Huddinge, Sweden, Clinical Gene Networks AB, Stockholm, Sweden (J.L.M.B.).
¹⁰ Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute, University of Eastern Finland, Finland (E.A.).
¹¹ A. I. Virtanen Institute, University of Eastern Finland, 70210, Kuopio, Finland, Heart Center and Gene Therapy Unit, Kuopio University Hospital, 70210 Kuopio, Finland (S.Y.-H.).
¹² Department of Vascular Surgery, University Medical Center Utrecht, University of Utrecht, the Netherlands (G.J.d.B.).
¹³ Department of Cardiology, Division Heart & Lungs, University Medical Center Utrecht, University of Utrecht, the Netherlands (F.W.A.).
¹⁴ Durrer Center for Cardiogenetic Research, Netherlands Heart Institute, Utrecht, the Netherlands (F.W.A.).
¹⁵ Institute of Cardiovascular Science, Faculty of Population Health Sciences, University College London, United Kingdom (F.W.A.).
¹⁶ Institute of Health Informatics, University College London, London, United Kingdom (F.W.A.).

PMID: 30354327
DOI: 10.1161/CIRCGEN.117.002030

Abstract

Background: Tobacco smoking is a major risk factor for atherosclerotic disease and has been associated with DNA methylation (DNAm) changes in blood cells. However, whether smoking influences DNAm in the diseased vascular wall is unknown but may prove crucial in understanding the pathophysiology of atherosclerosis. In this study, we associated current tobacco smoking to epigenome-wide DNAm in atherosclerotic plaques from patients undergoing carotid endarterectomy.

Methods: DNAm at commonly methylated sites (cytosine-guanine nucleotide pairs separated by a phospho-group [CpGs]) was assessed in atherosclerotic plaque samples and peripheral blood samples from 485 carotid endarterectomy patients. We tested the association of current tobacco smoking with DNAm corrected for age and sex. To control for bias and inflation because of cellular heterogeneity, we applied a Bayesian method to estimate an empirical null distribution as implemented by the R package bacon. Replication of the smoking-associated methylated CpGs in atherosclerotic plaques was executed in the second sample of 190 carotid endarterectomy patients, and results were meta-analyzed using a fixed-effects model.

Results: Tobacco smoking was significantly associated to differential DNAm in atherosclerotic lesions of 4 CpGs (false discovery rate <0.05) mapped to 2 different genes ( AHRR, ITPK1) and 17 CpGs mapped to 8 genes and RNAs in blood. The strongest associations were found for CpGs mapped to the gene AHRR, a repressor of the aryl hydrocarbon receptor transcription factor involved in xenobiotic detoxification. One of these methylated CpGs were found to be regulated by local genetic variation.

Conclusions: The risk factor tobacco smoking associates with DNAm at multiple loci in carotid atherosclerotic lesions. These observations support further investigation of the relationship between risk factors and epigenetic regulation in atherosclerotic disease.

Keywords: DNA methylation; ardiovascular disease; atherosclerosis; quantitative trait loci; smoking; tobacco.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aged
Atherosclerosis / etiology
Atherosclerosis / genetics*
Carotid Artery Diseases / etiology
Carotid Artery Diseases / genetics*
CpG Islands / genetics
DNA Methylation*
Endarterectomy, Carotid / methods
Endarterectomy, Carotid / statistics & numerical data
Epigenesis, Genetic
Epigenomics / methods*
Female
Gene Expression Regulation
Genome-Wide Association Study / methods*
Humans
Male
Middle Aged
Plaque, Atherosclerotic / etiology
Plaque, Atherosclerotic / genetics
Smoking / adverse effects*

Grants and funding

Biotechnology and Biological Sciences Research Council/United Kingdom