Signaling pathway and physiological role of the alpha-1 adrenergic receptor in human osteoblasts

BackgroundIn recent years, the role of the sympathetic nervous system in bone metabolism has been revealed. Many studies have suggested that bone loss can be induced by continuously high sympathetic tone resulting from up-regulation of osteoclastogenesis and osteoclastic activity via β₂-adrenergic receptors. Although the expression of α-adrenergic receptors in osteoblasts and osteoclasts has been demonstrated, the physiological roles of these receptors in bone metabolism remain unclear. In the present review, we provide an account of the role of α₁-adrenergic receptors in bone metabolism.ConclusionExperimental studies in osteoblasts suggest that not only the suppression of β₂-adrenergic receptors but also the activation of α₁-adrenergic receptors could lead to a treatment for osteoporosis. Studying the signaling pathway will help elucidate the mechanism underlying the regulation of bone metabolism via the α₁-adrenergic receptor and also facilitate the development of a novel therapeutic strategy for osteoporosis.