Fluorescently labeled bone formation in hibernating grizzly bears (200x magnification) used to measure mineral apposition rate (MARN)

Dr. Seth Donahue

Similar to muscles, bones weaken during physical inactivity. In this condition, termed disuse osteoporosis, bones become more porous and the risk of fracture greatly increases. Clinically, this is an important problem for stroke and spinal cord injured patients and astronauts in the low-gravity environment of space. Bears, which are inactive during hibernation for half of their lives, are uniquely resistant to disuse osteoporosis. Mechanical testing and microscopic examination of bones from hibernating and active grizzly bears show that there is no loss of mineral and mechanical strength.  Furthermore, bone formation rate is maintained and their bones actually become less porous during hibernation. Dr. Seth Donahue’s laboratory is trying to identify the biomolecules in the bear's bloodstream which may be responsible for this phenomenon, and ultimately used to develop new pharmaceutical treatments for human osteoporosis.

Aaron Maki – Senior BME undergraduate research fellow

Seth W. Donahue

Ph.D.
Associate Professor

Email: swdonahu@mtu.edu

Office: 309 M&M Building

Telephone: 906-487-1729
Fax: 906-487-1717

Michigan Technological University
Department of Biomedical Engineering
309 Minerals and Materials Eng. Bldg.
1400 Townsend Drive
Houghton, MI 49931-1295