How can parathyroid hormone (PTH) and parathyroid hormone-related peptide (PTHrP) be anabolic agents for treating osteoporosis?
Persistently elevated serum PTH levels (hyperparathyroidism) or PTHrP levels promote osteoclastic bone resorption, hypercalcemia, and bone loss. In contrast, intermittent daily pulses of exogenous PTH or PTHrP actually stimulate osteoblast differentiation, proliferation, and survival, resulting in osteoid formation and increased bone mass. They also decrease the production of the bone inhibiting protein, sclerostin, from osteocytes.
