ORIGINAL ARTICLES   

Minerva Medica 2015 August;106(4):221-31

Copyright © 2015 EDIZIONI MINERVA MEDICA

language: English

Association between alterations in global DNA methylation and predisposing factors in diabetes: a high pressure liquid chromatography based study

Maghbooli Z. ¹, Hossein-Nezhad A. ^{2, 3}, Larijani B. ¹, Pasalar P. ¹, Keshtkar A. A. ² ✉

¹ Endocrinology and Metabolism Research Center, Endocrinology and Metabolism, Clinical Sciences Institute, Tehran, University of Medical Sciences, Tehran, Iran; ² Osteoporosis Research Center, Endocrinology and Metabolism, Clinical Sciences Institute, Tehran, University of Medical Sciences, Tehran, Iran; ³ Department of Medicine, Section of Endocrinology, Nutrition and Diabetes, Vitamin D, Skin and Bone Research Laboratory, Boston University Medical Center, Boston, MA, USA

AIM: The aim of this study was to investigate the relationship between inter-individual global DNA methylation and diabetes predisposing factors.
METHODS: The 5-methyl cytosine content was assessed by reverse phase high pressure liquid chromatography (RP-HPLC) of peripheral blood leukocytes obtained from 178 type 2 diabetes patients to determine individual global DNA methylation status.
RESULTS: There was a positive significant correlation between diabetes duration and DNA methylation levels (P=0.002) with increasing levels of DNA methylation associated with age (P=0.047). There was no significant correlation between DNA methylation levels and HbA1c (P=0.15). No significant differences were observed between patients with and without diabetes predisposing factors including: hypertension (P=0.772), dyslipidemia (P=0.617), insulin resistance (homeostatic model assessment index) (P=0.156) and obesity (P=0.609). As such, the duration of diabetes (>10 years) was the most important predictor of global DNA methylation levels in diabetic patients after adjusting for age and sex (P=0.023).
CONCLUSION: Our findings indicate that chronic hyperglycemic exposure plays an independent role in global DNA methylation levels in type 2 diabetes patients.