What is the connection between high doses of cortisone and developing osteoporosis? Researchers at Washington University School of Medicine in St. Louis have identified osteoclasts (cells that dismantle or breakdown old bone) as the critical link.

One researcher developed a line of genetically modified mice in which receptors for cortisone could be eliminated in individual cell types. Through cross-breeding, researchers produced a line of mice whose bone-dismantling osteoclasts lacked cortisone receptors. Researchers then gave cortisone to these mice and the bone-weakening effect of the cortisone was blocked. Additionally, researchers found that cortisone inhibits the ability of osteoclasts to dismantle old bone in genetically normal mice.

Cortisone in high doses is the second most common cause of osteoporosis. Cortisone is a naturally produced steroid by the adrenal gland. Cortisone is also synthesized for clinical use and is used to treat rheumatoid arthritis, and many other inflammatory or autoimmune conditions.

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Researchers feel the findings are a start. Focusing on osteoclasts going forward may allow them to develop therapeutic targets.

More Related Resources:

• Osteoporosis Screening Quiz
• Osteoporosis Risk Factors
• Are You at Risk for Weak Bones?
• Osteoporosis: Factors Affecting Peak Bone Mass
• Increased Risk of Osteoporosis with Rheumatic Disease
• What Arthritis Patients Should Know About Osteoporosis

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