A press release from the NIH yesterday announced a new discovery about the biology of bone remodeling that may lead to a new way to treat osteoporosis.  The study, (published in Nature), described how a compound found in the blood helps control the development of bone destroying cells called osteoclasts.  (Osteoclasts break down bone while osteoblasts build new bone – The balance between these two cell types determines whether bone density and strength stays the same, increases or decreases.)

Lead for New Treatments for Osteoporosis
The effects of this compound, (sphingosine-1-phosphate), on osteoclasts may lead to the development of new treatments for osteoposorisis since the existing treatments have focused on the activity of more mature osteoclasts and osteoblasts.  That is, by medically modifying the activity or levels of sphingosine-1-phosphate, it might be possible to adjust the overall population of osteoclasts, and thus reverse or halt osteoporosis in an individual patient.  However, because sphingosine-1-phosphate has also been found to be involved with the the development of immune system cells, developing such a treatment might be tricky.  It is also possible that there are sub-types of  this compound, some of which are involved in bone cell development, while others modulate immune cell production…. But only more research will lead to these answers.

Need for New Treatments for Osteoporosis
Osteoporisis is a significant medical problem, and one that certainly will be growing with the aging of our population.  As the National Institute of Arthritis Musculoskeletal and Skin Diesease summarizes:

• Osteoporosis is a major public health threat for 44 million Americans, 68 percent of whom are women.
• In the U.S. today, 10 million individuals already have osteoporosis and 34 million more have low bone mass, placing them at increased risk for this disease.
• One out of every two women and one in four men over 50 will have an osteoporosis-related fracture in their lifetime.
• More than 2 million American men suffer from osteoporosis, and millions more are at risk. Each year, 80,000 men have a hip fracture and one-third of these men die within a year.
• Osteoporosis can strike at any age.
• Osteoporosis is responsible for more than 1.5 million fractures annually, including 300,000 hip fractures, approximately 700,000 vertebral fractures, 250,000 wrist fractures, and more than 300,000 fractures at other sites.
• Based on figures from hospitals and nursing homes, the estimated national direct expenditures for osteoporosis and related fractures total $14 billion each year.

Incentives for Finding New Treatments
There certainly are incentives for developing new osteoporosis treatments.  Not only is the population aging, but while less use of hormone replacement therapy by postmenopausal women may be leading to lower rates of breast cancer, it may also increase the incidence of osteoporosis. These and other factors will likely keep the market for osteoporosis treatments growing.  It is already over $5 billion, not counting nutritional supplements and other complementary treatments.  Time will tell if this new discovery leads to new treatments for osteoporosis (and possibly other bone diseases like rheumatoid arthritis), but if we don’t experiment, the answer will certainly be no.