Calcitonin gene related peptide (CGRP), a naturally-occurring neuropeptide, has the potential to prevent postmenopausal bone loss.
CGRP in animals stimulates osteoblast proliferation and inhibits osteoclastic bone resorption, according to a Yale University study presented Thursday in poster exhibit A 46.
Researchers gave ovariectomized rats and the sham controls daily subcutaneous injections of either CGRP or saline.
At the end of 28 days, ovariectomy had induced a 35 percent decrease in bone volume in the proximal tibia of the rats injected with saline, said laboratory director Agnes Vignery, DDS, PhD, associate professor, department of orthopaedics and rehabilitation, Yale University.
"Rats injected with CGRP did not lose bone-despite undergoing ovariectomy," said Dr. Vignery. "CGRP appears to prevent bone loss by controlling the production of cytokines and growth factors by bone and immune cells."
Results of the study show that CGRP prevented the metabolic changes-and the associated appetite increase and weight gain-that usually accompanies ovariectomy.
Dr. Vignery expects a similar benefit will be produced in postmenopausal women.
"In the body, cells talk to one another, stimulating or inhibiting tissue metabolism," said Dr. Vignery. "Injecting CGRP into this interaction is a new way to control metabolism."
CGRP is a nontoxic, natural molecule made by the nerves and located inside the sensory nerve fibers.
"The aging process decreases nervous system function, which could reduce CGRP levels, necessitating older people to obtain CGRP from external sources," said Dr. Vignery.
Among CGRP's other benefits, the neuropeptide stimulates the production of insulin-like growth factor (IGF-1) and reduces blood pressure. CGRP also inhibits production of tumor necrosis factor alpha, which has been implicated in the pathophysiology of postmenopausal bone loss.
Co-authors of the study with Dr. Vignery are orthopaedic surgeon Andrew Gutow, MD, fellow, department of orthopaedics, University of Southern California, Los Angeles, and Karine Valentijn, PhD, post-doctoral associate, department of orthopaedics and rehabilitation, Yale University.
|1996 Academy News Index|
Last modified 27/September/1996