European Journal of Applied Physiology

, Volume 113, Issue 2, pp 519–528

Exercise and diet-induced weight loss attenuates oxidative stress related-coronary vasoconstriction in obese adolescents

  • Zhaohui Gao
  • Marsha Novick
  • Matthew D. Muller
  • Ronald J. Williams
  • Samson Spilk
  • Urs A. Leuenberger
  • Lawrence I. Sinoway
Original Article

DOI: 10.1007/s00421-012-2459-9

Cite this article as:
Gao, Z., Novick, M., Muller, M.D. et al. Eur J Appl Physiol (2013) 113: 519. doi:10.1007/s00421-012-2459-9

Abstract

Obesity is a disease of oxidative stress (OS). Acute hyperoxia (breathing 100 % O2) can evoke coronary vasoconstriction by the oxidative quenching of nitric oxide (NO). To examine if weight loss would alter the hyperoxia-related coronary constriction seen in obese adolescents, we measured the coronary blood flow velocity (CBV) response to hyperoxia using transthoracic Doppler echocardiography before and after a 4-week diet and exercise regimen in 6 obese male adolescents (age 13–17 years, BMI 36.5 ± 2.3 kg/m2). Six controls of similar age and BMI were also studied. The intervention group lost 9 ± 1 % body weight, which was associated with a reduced resting heart rate (HR), reduced diastolic blood pressure (BP), and reduced RPP (all P < 0.05). Before weight loss, hyperoxia reduced CBV by 33 ± 3 %. After weight loss, CBV only fell by 15 ± 3 % (P < 0.05). In the control group, CBV responses to hyperoxia were unchanged during the two trials. Thus weight loss: (1) reduces HR, BP, and RPP; and (2) attenuates the OS-related coronary constrictor response seen in obese adolescents. We postulate that: (1) the high RPP before weight loss led to higher myocardial O2 consumption, higher coronary flow and greater NO production, and in turn a large constrictor response to hyperoxia; and (2) weight loss decreased myocardial oxygen demand and NO levels. Under these circumstances, hyperoxia-induced vasoconstriction was attenuated.

Keywords

Obesity Weight loss Coronary circulation 

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Zhaohui Gao
    • 1
  • Marsha Novick
    • 2
  • Matthew D. Muller
    • 1
  • Ronald J. Williams
    • 2
  • Samson Spilk
    • 1
  • Urs A. Leuenberger
    • 1
  • Lawrence I. Sinoway
    • 1
    • 3
  1. 1.Penn State Hershey Heart and Vascular InstituteThe Milton S. Hershey Medical Center, The Pennsylvania State University College of MedicineHersheyUSA
  2. 2.Penn State Children’s HospitalThe Milton S. Hershey Medical Center, The Pennsylvania State University College of MedicineHersheyUSA
  3. 3.Department of Medicine, H047The Milton S. Hershey Medical Center, The Pennsylvania State University College of MedicineHersheyUSA

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