title: Circulating cell-free DNA, telomere length and bilirubin in the Vienna Active Ageing Study: exploratory analysis of a randomized, controlled trial.
abstract: Telomere length (TL) in blood cells is widely used in human studies as a molecular marker of ageing. Circulating cell-free DNA (cfDNA) as well as unconjugated bilirubin (UCB) are dynamic blood constituents whose involvement in age-associated diseases is largely unexplored. To our knowledge, there are no published studies integrating all three parameters, especially in individuals of advanced age. Here we present a secondary analysis from the Vienna Active Aging Study (VAAS), a randomized controlled intervention trial in institutionalized elderly individuals (n = 101). Using an exploratory approach we combine three blood-based molecular markers (TL, UCB and cfDNA) with a range of primary and secondary outcomes from the intervention. We further look at the changes occurring in these parameters after 6-month resistance exercise training with or without supplementation. A correlation between UCB and TL was evident at baseline (p < 0.05), and both were associated with increased chromosomal anomalies such as nucleoplasmatic bridges and nuclear buds (p < 0.05). Of the three main markers explored in this paper, only cfDNA decreased significantly (p < 0.05) after 6-month training and dietary intervention. No clear relationship could be established between cfDNA and either UCB or TL. The trial was registered at ClinicalTrials.gov (NCT01775111).
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
authors.forename: Anela
authors.initials: A
authors.lastname: Tosevska
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Franzke
authors.affiliation: Centre for Sport Science and University Sports, Department of Sport and Exercise Physiology, University of Vienna, Auf der Schmelz 6, 1150 Vienna, Austria.
authors.forename: Marlene
authors.initials: M
authors.lastname: Hofmann
authors.affiliation: Department of Nutritional Sciences, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
authors.forename: Immina
authors.initials: I
authors.lastname: Vierheilig
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
authors.forename: Barbara
authors.initials: B
authors.lastname: Schober-Halper
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Oesen
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.|Queensland University of Technology, Faculty of Health, School of Biomedical Sciences, Institute of Health and Biomedical Innovation (IHBI), Tissue Repair and Regeneration Group, 60 Musk Avenue, Kelvin Grove Campus, Brisbane, QLD 4059, Australia.
authors.forename: Oliver
authors.initials: O
authors.lastname: Neubauer
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.|Centre for Sport Science and University Sports, Department of Sport and Exercise Physiology, University of Vienna, Auf der Schmelz 6, 1150 Vienna, Austria.
authors.forename: Barbara
authors.initials: B
authors.lastname: Wessner
authors.affiliation: Research Platform Active Ageing, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.|Department of Nutritional Sciences, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Wagner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D001663:Bilirubin / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D000073888:Cell-Free Nucleic Acids / Q000097:blood*; D005260:Female; D006801:Humans; D007326:Institutionalization; D008297:Male; D055070:Resistance Training; D016615:Telomere / Q000378:metabolism*; D059505:Telomere Homeostasis
chemical_list: D015415:Biomarkers; D000073888:Cell-Free Nucleic Acids; D001663:Bilirubin