Parathyroid hormone stimulation of noncanonical Wnt signaling in bone.

In bone, parathyroid hormone (PTH) exerts either a catabolic or an anabolic effect depending on its method of administration. This paradoxical action has led to the use of PTH as an effective treatment for osteoporosis. The Wnt family of signaling proteins has a critical role in multiple events, which are necessary for proper animal development and survival, yet their exact method of action in bone remains elusive. We have uncovered a novel link between Wnt-4 and PTH. We think that, in bone, Wnt-4 signaling in response to PTH implicates cross-talk of multiple signaling pathways. This work hopes to further elucidate Wnt signaling in bone and provide greater understanding of PTH's anabolic effects in bone.