Pharmaceutical Research

, Volume 24, Issue 2, pp 328–335 | Cite as

Selective Androgen Receptor Modulator (SARM) Treatment Prevents Bone Loss and Reduces Body Fat in Ovariectomized Rats

  • Jeffrey D. Kearbey
  • Wenqing Gao
  • Ramesh Narayanan
  • Scott J. Fisher
  • Di Wu
  • Duane D. Miller
  • James T. DaltonEmail author
Research Paper



This study was conducted to examine the bone and body composition effects of S-4, an aryl-propionamide derived Selective Androgen Receptor Modulator (SARM) in an ovariectomy induced model of accelerated bone loss.


One hundred twenty female Sprague–Dawley rats aged to twenty-three weeks were randomly assigned to twelve treatment groups. Drug treatment was initiated immediately following ovariectomy and continued for one hundred twenty days. Whole body bone mineral density (BMD), body composition, and lumbar vertebrae BMD were measured by dual energy x-ray absorptiometry. More stringent regional pQCT and biomechanical strength testing was performed on excised femurs.


We found that S-4 treatment maintained whole body and trabecular BMD, cortical content, and increased bone strength while decreasing body fat in these animals.


The data presented herein show the protective skeletal effects of S-4. Our previous reports have shown the tissue selectivity and muscle anabolic activity of S-4. Together these data suggest that S-4 could reduce the incidence of fracture via two different mechanisms (i.e., via direct effects in bone and reducing the incidence of falls through increased muscle strength). This approach to fracture reduction would be advantageous over current therapies in these patients which are primarily antiresorptive in nature.

Key words

androgen bone osteoporosis rat model SARM 



The outstanding technical assistance and advice of Juhyun Kim, Dr. Jun Yang, Dr. Victor Shen, and Dr. Mitch Steiner are gratefully acknowledged. Supported by a grant from GTx, Inc., Memphis, TN.


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Copyright information

© Springer Science+Business Media, LLC 2006

Authors and Affiliations

  • Jeffrey D. Kearbey
    • 1
    • 2
  • Wenqing Gao
    • 1
  • Ramesh Narayanan
    • 2
  • Scott J. Fisher
    • 1
  • Di Wu
    • 1
  • Duane D. Miller
    • 2
    • 3
  • James T. Dalton
    • 1
    • 2
    • 4
    Email author
  1. 1.College of Pharmacy, Division of PharmaceuticsThe Ohio State UniversityColumbusUSA
  2. 2.Drug DiscoveryGTx, Inc.MemphisUSA
  3. 3.College of Pharmacy, Department of Pharmaceutical SciencesUniversity of Tennessee, Graduate Health Sciences CenterMemphisUSA
  4. 4.College of PharmacyThe Ohio State UniversityColumbusUSA

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