New techniques may help scientists understand and manipulate bone remodeling
Osteoporosis is a disease categorized by brittle bones and increased risk of fracture. Individuals with osteoporosis, and diseases like it, have access to a number of treatments but no permanent solution. However, that may be about to change thanks to a University of Akron researcher awarded a $329,383 National Science Foundation grant to study how cells communicate to regrow bone tissue.
When you injure a bone you expect that, given time, the bone will heal itself. While this is the case for many healthy individuals, some people suffer from bone diseases in which cells that remodel bone do not effectively communicate with the cells meant to signal repairs. This can result in brittle or deformed bones and poor skeletal health.
Bone remodeling is a process involving mature bone tissue being removed from the skeleton by cells called osteoclasts, and being replaced with new bone tissue by cells called osteoblasts. In mechanically-induced bone remodeling, both the bone-forming and bone-removing cells are believed to receive signals from cells called osteocytes. These osteocytes seem to function like managers of a construction site, making sure that demolition of bone is occurring in areas where bone is no longer needed, and that bone formation is occurring in areas of injury or growth.
While this theory is generally accepted, there are still parts of the process not fully understood. Current research techniques study one cell type at a time, so signals between cells cannot be analyzed effectively.
Dr. Marnie Saunders, associate dean of biomedical engineering at the University of Akron, intends to expand the ways in which these cells can be observed. She is beginning research on an in vitro, "lab-on-a-chip" bone remodeling platform. The platform will consist of a silicon "chip" containing small holes in which researchers can grow different configurations of bone cells. This will allow her to observe the cellular communication process and measure the outcomes of that communication (such as bone formation and restoration). By manipulating variables in the process and observing key differences, Saunders is hopeful the contribution of each cell type in the overall process will soon be understood.
"Observing this process on a cellular level is pivotal to improving bone health and lessening the impact of bone-degenerative diseases," Saunders states. "The project hopes to evaluate the contribution of soluble activity, direct cell contact and cell communication to bone tissue remodeling in the lab setting."
If the project is successful, this platform could be used to test the safety and efficacy of medications meant to halt bone loss, such as drugs for osteoporosis and bone metastasis. Microgravity (spaceflight) causes accelerated bone loss similar to osteoporosis, and current methods study the phenomena through laboratory rodents. However, the success of this platform could mean sending the lab-on-a-chip into space in place of animals to study the effects of microgravity on bone remodeling.
Dr. Saunders has received more than $8.7 million to date in research support from government and private foundations. She hopes her most recent grant will open doors to studying bone remodeling and attack the issue of bone deterioration at the source.