Two Widely-Used Drugs for Erectile Dysfunction Could Be Repurposed to Treat Osteoporosis

Newswise — Why the Research Is Interesting: Osteoporosis is a global public health problem that affects almost 200 million people worldwide. Erectile dysfunction is the most common male sexual dysfunction in the aging population, with more than 70% of men over the age of 70 suffering from this. Two seemingly unrelated multifactorial diseases share a very important molecular pathway. PDE5A inhibitors are widely and safely used drugs for erectile dysfunction. The research shows that both drugs act in the formation of new bone and reduced removal of old bone. Due to this, the drugs could potentially be utilized for co-treating erectile dysfunction and osteoporosis in men of advancing ages, as well as for treating osteoporosis in postmenopausal women.

Journal: Proceedings of the National Academy of Sciences

Lead Author: Se-Min Kim, MD, Associate Director, Translational Research, Mount Sinai Bone Program, Assistant Professor of Medicine (Endocrinology, Diabetes and Bone Disease) at the Icahn School of Medicine at Mount Sinai

*Co-Senior investigators: Mone Zaidi, MD, PhD, MACP, Director of the Mount Sinai Bone Program and Professor of Medicine (Endocrinology, Diabetes and Bone Disease) at the Icahn School of Medicine at Mount Sinai; Tony Yuen, PhD, Associate Director of Research for the Mount Sinai Bone Program and Assistant Professor of Medicine at the Icahn School of Medicine at Mount Sinai

What (Study Measures): The objective was to examine the comprehensive skeletal effect of blocking phosphodiesterase (PDE) 5A, an enzyme that affects cell signaling in blood vessel walls. Inhibiting PDE5 can relax muscles and increase blood flow to specific areas of the body. The team focused specifically on two PDE5 inhibitors; tadalafil and vardenafil.

Results: The target enzyme, PDE5A, was found to be expressed in mouse skeletal tissue and human bone cells. It was also shown in precursors of osteoblasts, cells responsible for bone formation. Both drugs that block PDE5A enhanced osteoblastic bone formation and significantly increased bone mineral density in mice. Overall, the direct effect on the bone from tadalafil and vardenafil resulted in a net bone gain.

Study Conclusions: These findings support testing of the two commonly-used erectile dysfunction drugs in the hopes of a potential treatment involving patients with osteoporosis.

Mount Sinai’s Dr. Zaidi about the research:

“This is a remarkable study suggesting that a common class of FDA-approved medications that have a proven safety record for erectile dysfunction for men and pulmonary hypertension for both women and men can be repurposed for osteoporosis treatment. Also enshrined within the study is the interdisciplinary flavor of team science and innovation that Dr. Kim and Dr. Yuen have demonstrated nicely.”

Funding: This study was funded in part by the National Institutes of Health (R01AR67066; R01DK113627; and U19AG60917)