Weight loss in obese older adults increases serum sclerostin and impairs hip geometry but both are prevented by exercise training

Authors

  • Reina Armamento-Villareal,

    1. Divisions of Geriatrics and Endocrinology, University of New Mexico School of Medicine, Albuquerque, NM, USA
    2. Sections of Geriatrics and Endocrinology, New Mexico VA Health Care System, Albuquerque, NM, USA
    Search for more papers by this author
  • Corinn Sadler,

    1. Divisions of Geriatrics and Endocrinology, University of New Mexico School of Medicine, Albuquerque, NM, USA
    2. Sections of Geriatrics and Endocrinology, New Mexico VA Health Care System, Albuquerque, NM, USA
    Search for more papers by this author
  • Nicola Napoli,

    1. Endocrinology, Campus Biomedico, Rome, Italy
    Search for more papers by this author
  • Krupa Shah,

    1. Geriatrics and Aging, University of Rochester School of Medicine, Rochester, NY, USA
    Search for more papers by this author
  • Suresh Chode,

    1. Division of Geriatrics and Nutritional Science, Washington University School of Medicine, St. Louis, MO, USA
    Search for more papers by this author
  • David R Sinacore,

    1. Department of Physical Therapy, Washington University School of Medicine, St. Louis, MO, USA
    Search for more papers by this author
  • Clifford Qualls,

    1. Department of Mathematics and Statistics, University of New Mexico School of Medicine, Albuquerque, NM, USA
    Search for more papers by this author
  • Dennis T Villareal

    Corresponding author
    1. Divisions of Geriatrics and Endocrinology, University of New Mexico School of Medicine, Albuquerque, NM, USA
    2. Sections of Geriatrics and Endocrinology, New Mexico VA Health Care System, Albuquerque, NM, USA
    3. Division of Geriatrics and Nutritional Science, Washington University School of Medicine, St. Louis, MO, USA
    • New Mexico VA Health Care System, 1501 San Pedro SE, Albuquerque, NM, USA.
    Search for more papers by this author

  • Presented at the 2011 Annual Meeting of the American Society for Bone and Mineral Research, San Diego, CA, USA.

Abstract

We reported that weight loss induces bone loss which is prevented by exercise training; however, the mechanism for this observation remains unclear. Sclerostin, an inhibitor of bone formation, has been found to increase in states of unloading and may mediate the changes in bone metabolism associated with weight loss and exercise. The objective of the study was to determine the effect of lifestyle intervention in obese older adults on sclerostin levels, and on hip geometry parameters. A total of 107 obese (body mass index [BMI] ≥ 30 kg/m2) older (≥65 years) adults were randomly assigned to control, diet, exercise, and combined diet-exercise for 1 year. Sclerostin levels were measured by ELISA at baseline, 6 months, and 12 months, while hip geometry parameters were obtained from bone mineral density (BMD) images done by dual-energy X-ray absorptiometry using hip structure analysis at baseline and 12 months. Both the diet and diet-exercise groups had significant decreases in body weight (−9.6% and −9.4%, respectively), whereas weight was stable in the exercise and control groups. Sclerostin levels increased significantly and progressively in the diet group (6.6% ± 1.7% and 10.5% ± 1.9% at 6 and 12 months, respectively, all p < 0.05), whereas they were unchanged in the other groups; in particular, they were stable in the diet-exercise group (0.7% ± 1.6% and 0.4% ± 1.7% at 6 and 12 months, respectively, all p = 0.05). Hip geometry parameters showed significant decreases in cross-sectional area, cortical thickness, and BMD; and increases in buckling ratio at the narrow neck, intertrochanter, and femoral shaft. These negative changes on bone geometry were not observed in the diet-exercise group. Significant correlations between changes in sclerostin and changes in certain hip geometry parameters were also observed (p < 0.05). In conclusion, the increase in sclerostin levels with weight loss that was prevented by exercise may partly mediate the negative effects of weight loss on bone metabolism and the osteoprotective effect of exercise training. © 2012 American Society for Bone and Mineral Research.

Ancillary