Osteocytes, bone remodeling and parathyroid hormone

Osteocytes, the longest living bone cells, have garnered much of the attention in the part they play in skeletal biology to orchestrate bone homeostasis. Although the multifunctional role of osteocytes in bone remodeling has been recognized, knowledge about the activity of important signaling molecules in osteocytes in this process are limited and far from being clearly depicted than osteoblast’s and osteoclast’s involvement. Stimulating the function of bone-forming osteoblasts and controlling osteoclastic activity are the preferred pharmacological intervention for skeletal repair. A large variety of studies have been conducted in osteoblasts and osteoclasts on recombinant parathyroid hormone (PTH), an anabolic drug which proved to be effective for bone strength and clinical therapy. Studies in relation to newly functioning signaling molecules in osteocytes and PTH’s mode of action is becoming an intense area of investigation suggesting further the importance of these cells in bone anabolic action. The goal of this review is to discuss briefly the function and physiological roles of osteocytes and highlight a few recent findings on the PTH’s action in osteocyte signaling in health and disease. In this context this review in addition to Pubmed searches also borrows many literatures in bone and related fields from various publications.