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Pharmacological Intervention to Prevent Disuse Osteopenia (NAG91458)
Principal Investigator
Research Area:
Biomedical countermeasures
Skeletal physiology
Species Studied
Scientific Name: Rattus norvegicus Species: Rat

The objectives of this study were to determine whether bone loss can be prevented using a pharmacological treatment of parathyroid hormone (PTH) in conjunction with raloxifene, a synthetic selective estrogen receptor modulator (to prevent undesirable side effects associated with the use of natural estrogens). Additionally, the study determined whether this pharmacological intervention during long-term unloading of bone influences the recovery of bone after normal weight bearing is resumed. Finally, the use of PTH alone and in combination with raloxifene was assessed during recovery as a method to restore bone lost during long-term unloading.

Previous research has shown that bone loss due to disuse, including that induced during space flight, is a consequence of a disruption in the signal molecules that function as intermediaries between the mechanical and metabolic processes involved in bone loss. The endocrine hormones, like estrogen, have been shown to inhibit bone loss during unloading, whereas the parathyroid hormone (PTH), in contrast, has been shown to increase bone formation during unloading. The overlap in these two pathways of control will be utilized to explore a possible novel pharmacological method of intervention to mitigate bone loss during periods of disuse.

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Turner RT, Evans GL, Lotinun S, Lapke PD, Iwaniec UT ,and Morey-Holton E. Dose-response effects of intermittent PTH on cancellous bone in hindlimb unloaded rats. Journal of Bone and Mineral Research. 2007. January; 22(1):64-71. []

Bone and bones
Parathyroid hormones

Data Information
Data Availability
Archive is complete. Data sets are not publicly available but can be requested.
Data Sets+ Request data

16 alpha-hydroxyestrone
Bone loss
Bone mass
Bone turnover
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Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
BRC 01/01/2003 12/31/2005 1095 days

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Jessica Keune
Institutional Support
National Aeronautics and Space Administration (NASA)