title: Circulating MiRNAs as biomarkers of gait speed responses to aerobic exercise training in obese older adults.
abstract: Gait speed is a useful predictor of adverse outcomes, including incident mobility disability and mortality in older adults. While aerobic exercise training (AEX) is generally an effective therapy to improve gait speed, individual responses are highly variable. Circulating microRNAs (miRNAs) may contribute to inter-individual changes in gait speed with AEX. We examined whether plasma miRNAs are associated with gait speed changes (dGaitSp) in 33 obese older adults (age: 69.3±3.6 years, BMI: 34.0±3.1 kg/m2, 85% white, 73% women) who performed treadmill walking, 4 days/week for 5 months. Gait speed (baseline: 1.02±0.19 m/s; range of response: -0.2 to 0.35 m/s) was assessed using a 400 meter-fast-paced walk test. Using Nanostring technology, 120 out of 800 miRNAs were found to be abundantly expressed in plasma and 4 of these were significantly changed after AEX: miR-376a-5p increased, while miR-16-5p, miR-27a-3p, and miR-28-3p all decreased. In addition, baseline miR-181a-5p levels (r=-0.40, p=0.02) and percent changes in miR-92a-3p (r=-0.44, p=0.009) associated negatively with dGaitSp. Linear regression combined baseline miR-181a-5p and miR-92a-3p levels showed even stronger associations with dGaitSp (r=-0.48, p=0.005). These results suggest that circulating miR-181a-5p and miR-92a-3p may predict and/or regulate AEX-induced gait speed changes in obese older adults.
authors.affiliation: Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Sticht Center for Healthy Aging and Alzheimer's Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Tan
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Sticht Center for Healthy Aging and Alzheimer's Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Tina E
authors.initials: TE
authors.lastname: Brinkley
authors.affiliation: Center for Bioinformatics and Systems Biology, Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Keqin
authors.initials: K
authors.lastname: Liu
authors.affiliation: Department of Otolaryngology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Feng
authors.affiliation: Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27109, USA.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Marsh
authors.affiliation: Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Sticht Center for Healthy Aging and Alzheimer's Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Kritchevsky
authors.affiliation: Center for Bioinformatics and Systems Biology, Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Sticht Center for Healthy Aging and Alzheimer's Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Nicklas
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015444:Exercise / Q000502:physiology; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood*; D009765:Obesity / Q000097:blood / Q000503:physiopathology / Q000628:therapy*; D064797:Physical Conditioning, Human / Q000502:physiology*; D000072797:Walking Speed / Q000502:physiology*
chemical_list: D015415:Biomarkers; D035683:MicroRNAs
keywords: aerobic exercise; circulating miRNA; gait speed; inter-individual variation; older adults