Oral Presentation Australian & New Zealand Obesity Society 2016 Annual Scientific Meeting

Impact of Endurance Exercise Training on Adipocyte miRNA Expression in Overweight Men (#72)

Thomas Tsiloulis 1 , Joshua Pike 1 , David Powell 2 , Fernando J. Rossello 3 4 , Benedict J. Canny 1 5 , Ruth C.R. Meex 1 , Matthew J. Watt 1
  1. Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity program and the Department of Physiology, Monash University, Clayton, Victoria, Australia
  2. Monash Bioinformatics Platform, Faculty of Biomedical and Psychological Sciences, Monash University, Clayton, Victoria, Australia
  3. Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
  4. Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
  5. School of Medicine, Faculty of Health, University of Tasmania, Hobart, Tasmania, Australia

Adipocytes are major regulators of metabolism and dysregulated adipocyte function in obesity is linked to the metabolic syndrome. Endurance-exercise training improves adipocyte function; however, the molecular mechanisms that regulate the chronic adaptive responses are incompletely described. microRNAs (miRNAs) influence adipocyte differentiation and metabolism, yet their role in exercise-induced adipocyte phenotypes is unknown. We used next generation sequencing (NGS) to profile miRNA expression of adipocytes isolated from subcutaneous abdominal (ABD) and gluteofemoral (GF) adipose tissue of overweight men before and after six weeks of endurance-exercise training. Differentially expressed miRNAs were over-expressed or silenced in 3T3-L1 adipocytes and lipid metabolism examined. NGS identified 526 miRNAs in adipocytes and there were no statistical differences in miRNA expression when comparing the pre- and post-training samples for both ABD and GF adipocytes. miR-10b expression was increased in ABD compared with GF, while miR-204, miR-3613 and miR-4532 were more highly expressed in GF compared with ABD adipocytes. Blocking miR-10b in adipocytes suppressed ß-adrenergic lipolysis but had a minor effect on lipid metabolism in general. Unlike their critical role in adipogenesis, stable changes in miRNA expression do not play a prominent role in the regulation of adipocyte function in response to endurance-exercise training.