title: Interactions of Short-Term and Chronic Treadmill Training With Aging of the Left Ventricle of the Heart.
abstract: With aging, there is a decline in cardiac function accompanying increasing risk of arrhythmias. These effects are likely to be mechanistically associated with age-associated changes in calcium regulation within cardiac myocytes. Previous studies suggest that lifelong exercise can potentially reduce age-associated changes in the heart. Although exercise itself is associated with changes in cardiac function, little is known about the interactions of aging and exercise with respect to myocyte calcium regulation. To investigate this, adult (12 months) and old (24 months) C57/Bl6 mice were trained using moderate-intensity treadmill running. In response to 10 weeks' training, comparable cardiac hypertrophic responses were observed, although aging independently associated with additional cardiac hypertrophy. Old animals also showed increased L- and T-type calcium channels, the sodium-calcium exchange, sarcoendoplasmic reticulum calcium ATPase, and collagen (by 50%, 92%, 66%, 88%, and 113% respectively). Short-term exercise training increased D-type and T-type calcium channels in old animals only, whereas an increase in sodium-calcium exchange was seen only in adult animals. Long-term (12 months) training generally opposed the effects of aging. Significant hypertrophy remained in long-term trained old animals, but levels of sarcoendoplasmic reticulum calcium ATPase, sodium-calcium exchange, and collagen were not significantly different from those found in the adult trained animals.
authors.affiliation: School of Biomedical Sciences, University of Leeds.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Walton
authors.affiliation: Department of Biological Sciences, University of Hull.
authors.forename: Sandra A
authors.initials: SA
authors.lastname: Jones
authors.affiliation: School of Biomedical Sciences, University of Leeds.
authors.forename: Kerry A
authors.initials: KA
authors.lastname: Rostron
authors.affiliation: Institute of Ageing & Chronic Disease, Faculty of Health and Life Sciences, University of Liverpool.
authors.forename: Anna C
authors.initials: AC
authors.lastname: Kayani
authors.affiliation: Institute of Ageing & Chronic Disease, Faculty of Health and Life Sciences, University of Liverpool.
authors.forename: Graeme L
authors.initials: GL
authors.lastname: Close
authors.affiliation: Institute of Ageing & Chronic Disease, Faculty of Health and Life Sciences, University of Liverpool.
authors.forename: Anne
authors.initials: A
authors.lastname: McArdle
authors.affiliation: School of Biomedical Sciences, University of Leeds. m.k.lancaster@leeds.ac.uk.
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Lancaster
mesh_terms: D000375:Aging; D000818:Animals; D020746:Calcium Channels, L-Type / Q000378:metabolism; D020747:Calcium Channels, T-Type / Q000378:metabolism; D020013:Calcium Signaling / Q000235:genetics; D006332:Cardiomegaly / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D004195:Disease Models, Animal; D005080:Exercise Test; D006352:Heart Ventricles / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009200:Myocardial Contraction; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000473:pathology*; D019831:Sodium-Calcium Exchanger / Q000378:metabolism
chemical_list: D020746:Calcium Channels, L-Type; D020747:Calcium Channels, T-Type; D019831:Sodium-Calcium Exchanger
keywords: Aging; Calcium regulation; Exercise; Fibrosis; Hypertrophy