The Effect of Aging on Skeletal Mechanoresponsiveness: Animal Studies - Skeletal Aging and Osteoporosis: Biomechanics and Mechanobiology - page 188

The Effect of Aging on Skeletal
Mechanoresponsiveness: Animal Studies
Akhilesh A. Kotiya and Matthew J. Silva
Abstract Growth and remodeling of skeletal tissue in response to its mechanical
environment is a well established phenomenon. Relatively little is known
regarding the interaction of aging and skeletal responses to mechanical loading,
although several early studies have contributed to the ''conventional wisdom'' that
old bones are relatively unresponsive. Development of non-pharmacological
therapies for treatment of skeletal pathologies requires better understanding of
such interactions, especially if aimed at maintaining or restoring bone mass in the
elderly. The use of intrinsic (e.g., running) and extrinsic (e.g., tibial compression)
loading models provide means to study age effects in animal studies. We identified
15 studies that address age effects explicitly, although only nine of these include a
truly old group (e.g., 18-24 months old for mice). Though the outcomes of the
studies have not been uniform, two general themes have emerged. First, bones
from old animals are mechano-responsive provided they are presented with an
appropriate stimulus. Second, it is unclear if bones from old animals are less
responsive than from younger animals, as there is evidence for and against this
view. Therefore, we advocate a re-examination of the conventional wisdom, and
offer a few guidelines for designing studies to address the questions regarding
aging and bone mechano-responsiveness.
A. A. Kotiya ( & )
Department of Biomedical Engineering, Dalhousie University,
Halifax, NS, Canada
e-mail: [e-mail]
M. J. Silva
Department of Orthopaedic Surgery, Washington University,
Saint Louis, MO, USA
e-mail: [e-mail]