Osteocalcin - A Vital Protein for Bone Formation...and More
In my last blog, I introduced the use of laboratory tests as THERAPEUTIC TARGETS for designing and monitoring treatment protocol in cases of excessive bone loss. There are quite a few lab tests that I use as indirect indicators of poor bone quality. When monitored through serial testing, the changes seen in these lab results (better or worse) can help determine therapeutic effectiveness. Over the next several blogs I will tell you about some of the most important tests that I use when working with patients with osteoporosis. Today, I would like to introduce one of my favorites, osteocalcin.
One of the most fascinating hormones in the body is osteocalcin. I write about this protein in my book, The Whole-Body Approach to Osteoporosis, because of it is probably the most important protein produced by the body during the formation of bone. In fact, bone formation cannot occur without it.
When osteoblast cells form areas of new bone in the skeleton, they begin by releasing osteocalcin which is then activated by vitamin K. Once activated, the osteocalcin stimulates the formation of new bone crystals that “patch” areas of weakened bone. Osteoporosis is typically the result of too much osteoclastic activity (the cells that resorb bone) but it can also be the result of too little osteoblastic bone formation. If the osteoblasts can’t keep pace with the amount of bone resorption by the osteoclasts, then there will be a net loss of bone. If this imbalance continues long term, it will eventually lead to osteoporosis. This is why osteocalcin can be such an important test when assessing a patient’s origin of bone loss. In my next blog, I will tell you what blood levels can tell us about this protein and how its numbers can infer a loss or gain of bone. I will also write about some of the other biological actions of osteocalcin (as a hormone...yes, your skeleton is actually an endocrine organ!)…such as memory and sex…and some VERY COOL new research just out that sheds even more light on osteocalcin’s vast biological role in human function.