A Delicate Balance

A delicate balance between bone formation and bone resorption is needed for Healthy Bone.  This balance is naturally present until menopause in a woman or “Low T” in a man.  The main players are OsteoBlasts, OsteoClasts, and OsteoCytes.

OsteoBlasts are cells that build bone by producing bone matrix (Anabolic).  OsteoClasts are cells that resorb or take away bone (Resorptive).  Both live on the surface of bone.  OsteoCytes live inside bone and control the balance of formation and resorption through the hormone Osteoprotegrin (OPG).  OPG supresses the number and activity of OsteoClasts.

Estradiol is the hormone that tells the OsteoCytes to make enough OPG to keep the Osteoclasts under control.  Women make Estradiol from Estrogen.  Men make Estradiol from Testosterone.  Women after menopause (about age 50) and men after about age 70 no longer make enough Estradiol to produce enough OPG.  Then it is Osteoclasts Gone Wild.

Modern Hormone Replacement Therapy (HRT) is an obvious possibility in a woman.  Estrogen is back on board.  Prolia (Denosumab in osteoporosis dose), and Evista (Raloxifene), are two novel osteoporosis medications designed to bring unruly OsteoClasts under control.  They both mimic the natural process, but in different ways.  We will address each in coming posts.

Take Back Control with whatever medication works best for you.

Jay Ginther, MD

Categorised in: Bone Health, Medications, Osteoporosis