Estrogen receptors alpha and beta in bone

- This review will highlight the role of estrogen receptors in bone.
- Estrogen receptors alpha and beta can partially compensate for each other.
- Estrogen receptor beta antagonizes many effects of estrogen receptor alpha in bone.

Estrogens are important for bone metabolism via a variety of mechanisms in osteoblasts, osteocytes, osteoclasts, immune cells and other cells to maintain bone mineral density. Estrogens bind to estrogen receptor alpha (ERα) and ERβ, and the roles of each of these receptors are beginning to be elucidated through whole body and tissue-specific knockouts of the receptors. In vitro and in vivo experiments have shown that ERα and ERβ antagonize each other in bone and in other tissues. This review will highlight the role of these receptors in bone, with particular emphasis on their antagonism.