Discovery could improve treatment for osteoporosis
A new discovery has revealed how osteocalcin, a protein, strengthens our bones, potentially opening the way to better therapeutics for fighting osteoporosis or brittle bones.
The research by Rensselaer Polytechnic Institute details how fractures in healthy bones begin with the creation of incredibly tiny holes, each only about 500 atoms across, within the bone's mineral structure.
In the case of a slip, trip, or fall, the force of the impact on a bone physically deforms a pair of joined proteins, osteopontin and osteocalcin, and results in the formation of nanoscale holes, the journal Proceedings of the National Academy of Sciences reported.
These holes, called dilatational bands, help to prevent further damage to the surrounding bone. However, if the force of the impact is too great - or if the bone is lacking osteopontin, osteocalcin, or both - the bone will crack and fracture, according to an institute statement.
The multi-university study, led by Deepak Vashishth, head of biomedical engineering at Rensselaer, is the first to give evidence of fracture at the level of bone's nanostructure.
Partnering with Rensselaer were Villanova University, the Hospital for Special Surgery in New York, and Yale University.
"This study is important because it implicates, for the first time, the role of osteocalcin in giving bone the ability to resist fracture," Vashishth said.
"Since osteocalcin is always the point of fracture, we believe that strengthening it could lead to a strengthening of the overall bone."
Recently, abnormalities in ostoecalcin production have been tied to type 2 diabetes as well as problems in reproductive health.
Vashishth's new study, however, is the first to explain the structural and mechanical importance of osteocalcin in bone.
"Currently, all of the advice for treating osteoporosis is related to calcium. We believe there's more to the story than just calcium, and the results of this new study raise an important question about vitamin K.
"Leafy green vegetables are the best source of vitamin K - wouldn't it be great if eating spinach and broccoli was not only healthy, but also good for your bones? We plan to investigate this link in future," Vashisth said.