PROOF JOURNAL OF BIOLOGICAL REGULATORS & HOMEOSTATIC AGENTS Vol. 28, no. 3, 0-0 (2014) 0393-974X (2014) Copyright © by BIOLIFE, s.a.s. This publication and/or article is for individual use only and may not be further reproduced without written permission from the copyright holder. Unauthorized reproduction may result in inancial and other penalties DISCLOSURE: ALL AUTHORS REPORT NO CONFLICTS OF INTEREST RELEVANT TO THIS ARTICLE. 409 Key words: DNA methylation, exercise, interleukin-6 Mailing address: Prof. Paula Robson-Ansley, Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK Tel.: +44 191 224 7774 e-mail: paula.ansley@northumbria.ac.uk The aim of the present study was to examine the relationship between interleukin (IL)-6 concentrations and DNA methylation in the peripheral blood mononuclear cells (PBMCs) of trained runners after a bout of prolonged, strenuous exercise. Eight healthy trained males completed a treadmill run at 60% vVO 2max for 120 min followed by a 5-km time trial in a fasted condition. Whole blood samples were taken prior to, immediately before and 24 h following exercise. From these samples, PBMCs were isolated for analysis and plasma IL-6 concentrations were measured. The methylation status of DNA extracted from PBMCs was analysed using the Illumina 27k methylation beadchip platform. Global DNA methylation status was unaltered immediately and up to 24 hours following a bout of prolonged exercise in comparison to pre- exercise. Despite no change in global DNA methylation, plasma IL-6 concentrations were signiicantly related to the DNA methylation status of 11 genes. Our study demonstrates that the methylome is stable, while discovering a novel link between exercise-induced increases in circulating IL-6 and the DNA methylation status of 11 individual genes. Based on our preliminary indings, the mechanisms by which changes in plasma IL-6 concentrations and DNA methylation in response to exercise interact require further study. DYNAMIC CHANGES IN DNA METHYLATION STATUS IN PERIPHERAL BLOOD MONONUCLEAR CELLS FOLLOWING AN ACUTE BOUT OF EXERCISE: POTENTIAL IMPACT OF EXERCISE-INDUCED ELEVATIONS IN INTERLEUKIN-6 CONCENTRATION P.J. ROBSON-ANSLEY 1,2 , A. SAINI 3 , C. TOMS 1 , L. ANSLEY 1 , I. WALSHE 4 , M.A. NIMMO 3 and J.A. CURTIN 5 1 Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne, UK; 2 Department of Physiological Sciences, Stellenbosch University, South Africa; 3 Department of Physiology and Pharmacology, Karolinska Institutet, Sweden; 4 School of Sport, Gannochy Sports Centre, University of Stirling, Stirling, UK; 5 The University of Manchester, Manchester Academic Health Science Centre, University Hospital of South Manchester NHS Foundation Trust, Manchester, UK Received October 10, 2013 – Accepted May 12, 2014 The molecular mechanisms involved in the physiological adaptation to exercise are not fully understood. Adaptation is predominantly driven by changes in gene expression, which may be governed by exercise-induced modiications to the epigenome (1). Epigenetics is the study of phenotypic or gene expression patterns heritable through cell division that are independent of changes in the underlying DNA sequence (2). Epigenetics has also been deined more broadly as the dynamic regulation of gene expression by sequence-independent mechanisms, including changes in DNA methylation and histone