title: Aerobic exercise training reduces cardiac function in adult male offspring exposed to prenatal hypoxia.
abstract: Intrauterine growth restriction (IUGR) has been associated with increased susceptibility to myocardial ischemia-reperfusion (I/R) injury. Exercise is an effective preventive intervention for cardiovascular diseases; however, it may be detrimental in conditions of compromised health. The aim of this study was to determine whether exercise training can improve cardiac performance after I/R injury in IUGR offspring. We used a hypoxia-induced IUGR model by exposing pregnant Sprague-Dawley rats to 21% oxygen (control) or hypoxic (11% oxygen; IUGR) conditions from gestational day 15 to 21. At 10 wk of age, offspring were randomized to a sedentary group or to a 6-wk exercise protocol. Transthoracic echocardiography assessments were performed after 6 wk. Twenty-four hours after the last bout of exercise, ex vivo cardiac function was determined using a working heart preparation. With exercise training, there was improved baseline cardiac performance in male control offspring but a reduced baseline cardiac performance in male IUGR exercised offspring (P < 0.05). In male offspring, exercise decreased superoxide generation in control offspring, while in IUGR offspring, it had the polar opposite effect (interaction P ≤ 0.05). There was no effect of IUGR or exercise on cardiac function in female offspring. In conclusion, in male IUGR offspring, exercise may be a secondary stressor on cardiac function. A reduction in cardiac performance along with an increase in superoxide production in response to exercise was observed in this susceptible group.
authors.affiliation: Department of Physiology, University of Alberta, Edmonton, Alberta, Canada; Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada; and Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Reyes
authors.affiliation: Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada; and Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Raven
authors.initials: R
authors.lastname: Kirschenman
authors.affiliation: Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada; and Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Anita
authors.initials: A
authors.lastname: Quon
authors.affiliation: Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada; and Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Jude S
authors.initials: JS
authors.lastname: Morton
authors.affiliation: Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada; and Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Amin
authors.initials: A
authors.lastname: Shah
authors.affiliation: Department of Physiology, University of Alberta, Edmonton, Alberta, Canada; Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada; and Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada sandra.davidge@ualberta.ca.
authors.forename: Sandra T
authors.initials: ST
authors.lastname: Davidge
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005317:Fetal Growth Retardation / Q000209:etiology* / Q000503:physiopathology; D005311:Fetal Hypoxia / Q000150:complications* / Q000503:physiopathology; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D009206:Myocardium / Q000378:metabolism; D005082:Physical Exertion; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D017207:Rats, Sprague-Dawley; D012307:Risk Factors; D012737:Sex Factors; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors; D016277:Ventricular Function, Left
chemical_list: D013481:Superoxides
keywords: aerobic exercise training; heart function; intervention; intrauterine growth restriction