Osteoporosis is an important health problem in the rapidly-aging demographic. Fragility
fractures are devastating consequences of osteoporosis. The most common treatment approach in
osteoporosis is inhibition of bone resorption with drugs like alendronate (ALN). Parathyroid
hormone (PTH) stimulates bone formation and is the only anabolic drug available. Dual therapy
with ALN and PTH is not as effective as single-drug therapy in preventing fracture. Bone
progenitor cells (MSCs) are recruited to sites of bone remodeling when a growth factor called
Transforming Growth Factor Beta (TGF-β1) is released from bone. Different osteoporosis
medicines may have differing effects on this process. The effects of ALN versus PTH on bone
progenitor recruitment in humans are unknown. This is a randomized, clinical trial of ALN,
PTH, and calcium and vitamin D in post-menopausal women with low bone mass. Women will be
treated for 3 months with ALN or PTH or calcium and vitamin D. Data collected will include
bone biopsies for histomorphometry and micro computed tomography (µCT), bone marrow aspirates
for molecular studies, peripheral blood to detect circulating bone progenitor cells and dual
X-ray absorptiometry. The investigators hypothesize that in humans, PTH will 1) increase bone
progenitor number, 2) enhance recruitment of bone progenitor cells to bone resorption sites,
and 3) increase bone progenitor number in peripheral circulation. Furthermore, the
investigators hypothesize that ALN treatment will have the opposite effect. Understanding the
differences in bone progenitor cell activity and recruitment during osteoporosis therapy will
provide a mechanistic rationale for effective use of PTH and anti-resorptive drugs in
osteoporosis treatment.
Phase:
N/A
Details
Lead Sponsor:
Johns Hopkins University
Treatments:
Alendronate Calcium Calcium, Dietary Ergocalciferols Teriparatide Vitamin D Vitamins