on September 28, 2009
Published online before print September 28, 2009, doi: 10.1161/HYPERTENSIONAHA.109.138917
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Submitted on July 8, 2009
From the Departments of Physiology and Pharmacology (V.P., A.D.B., R.L., M.J.P.), Medicine (R.L.), and Clinical Neurosciences (M.J.P.), Hotchkiss Brain Institute (M.J.P.), and Libin Cardiovascular Institute of Alberta (M.J.P.), Faculty of Medicine, and Faculty of Kinesiology (V.P., M.J.P.), University of Calgary, Calgary, Alberta, Canada; Alberta Health Services (C.M.F.), Calgary, Alberta, Canada. * To whom correspondence should be addressed. E-mail: poulin{at}ucalgary.ca.
Abstract—Increasing evidence exists suggesting an important role for oxidative stress in the pathogenesis and progression of hypertension in women via a decrease of NO production after menopause. Regular physical training has been shown to upregulate antioxidant enzymatic systems, which may slow down the usual increase of oxidative stress in postmenopausal women. The aims of this study were to determine the impact of fitness status on enzymatic antioxidant efficiency, oxidative stress, and NO production and to determine the associations among oxidative stress, enzymatic antioxidant and NO production, mean arterial blood pressure (MABP), and cerebrovascular conductance (CVC) in postmenopausal women (n=40; 50 to 90 years old). Physical fitness, physical activity, resting MABP, and CVC were measured. End product of NO, lipid peroxidation (malondialdehyde and 8-iso-prostaglandin F2
Revised on July 27, 2009
Effect of Cardiorespiratory Fitness on Vascular Regulation and Oxidative Stress in Postmenopausal Women
Vincent Pialoux;
), DNA oxidation (8-hydroxy-2'-deoxyguanosine), protein nitration (nitrotyrosine), antioxidant glutathione peroxidase, and catalase activities were measured in plasma. We identified significant negative associations between oxidative stress and indices of physical fitness (malondialdehyde: r=-0.33, P<0.05; 8-iso-prostaglandin F2: r=-0.39, P<0.05; 8-hydroxy-2'-deoxyguanosine: r=-0.35, P<0.05) and physical activity (malondialdehyde: r=-0.30, P<0.05; 8-iso-prostaglandin F2: r=-0.41, P<0.01; 8-hydroxy-2'-deoxyguanosine: r=-0.39, P<0.05). Conversely, glutathione peroxidase was positively correlated with fitness level (r=0.55; P<0.01). Finally, MABP and CVC were significantly associated with 8-hydroxy-2'-deoxyguanosine (MABP: r=0.36, P<0.05; CVC: r=-0.36, P<0.05), nitrotyrosine (MABP: r=0.39, P<0.05; CVC: r=-0.32, P<0.05), and the end product of NO (MABP: r=-0.57, P<0.01; CVC: r=0.44, P<0.01). These findings demonstrate that, after menopause, fitness level and regular physical activity mediate against oxidative stress by maintaining antioxidant enzyme efficiency. Furthermore, these results suggest that oxidative stress and NO production modulate MABP and CVC.
Key words: oxidative stress • antioxidant enzymes • NO end products • menopause • fitness • blood pressure