Dr. Xingming Shi of the Medical College of Georgia Institute of Molecular Medicine and Genetics found the short-acting protein GILZ that appears to make this desirable shift, and wants to understand better how it does it -- with the long-term goal of targeted therapies for osteoporosis and obesity.

"The pathways are parallel, and the idea is if you can somehow disrupt the fat production pathway, you will get more bone," Shi said in a statement. "Bone loss and fat gain also tend to happen with age and with use of the powerful, anti-inflammatory steroid hormones glucocorticoids."

As a person ages, the bone marrow microenvironment changes. The balance between the bone and fat pathway is broken and more fat cells accumulate, Shi said.

People can't take GILZ now, but another long-term goal is to develop a GILZ-like pill that would dramatically reduce fat production, Shi said.

The findings are published in the Journal of Cellular Biochemistry.