O steocytes are the most abundant cell type in the bone, comprising more than 90% of all cells within the bone matrix or on bone surfaces. Osteocytes are derived from osteoblasts and are entombed in the bone matrix during bone deposition. Osteocytes were originally thought to be rather inert cells whose function was limited to maintaining bone matrix locally. However, osteocytes are connected t...

www.BioTechniques.com 361 Vol. 52 | No. 6 | 2012 The coordinated actions of three different types of bone cells are required for bone remodeling in response to mechanical loading. On the surface of bone are osteoblasts, which form new bone, and osteoclasts, which remove bone. Located deeper within the bone matrix and housed in cave-like lacunae, are osteocytes, which function as the mechanosens...

Abstract Estrogen deficiency during post-menopausal osteoporosis leads to osteoclastogenesis and bone loss. Increased pro-osteoclastogenic signalling (RANKL/OPG) by osteocytes occurs following estrogen withdrawal (EW) is associated with impaired focal adhesions (FAs) a disrupted actin cytoskeleton. RANKL production mediated Hedgehog in osteocytes, pathway the primary cilium, ciliary structure t...

Osteoblasts and clasts were primary targets for the understanding of bone biopathology. In recent years, evidence has shifted attention to the osteocytes. The biology of induced tooth movement and jaw orthopedics should research the role of osteocytes and the specific effects of mediators such as RANKL and sclerostin. The sclerostin represents a regulatory molecule: When more bone is necessary,...

INTRODUCTION External mechanical forces on cells are known to influence cytoskeletal structure and thus cell shape. Mechanical loading in long bones is unidirectional along their long axes, whereas the calvariae are loaded at much lower amplitudes in different directions. We hypothesised that if osteocytes, the putative bone mechanosensors, can indeed sense matrix strains directly via their cyt...

Bone has the capacity to alter its mass and structure to its mechanical environment. Osteocytes are the predominant bone cells and it is generally accepted that the osteocytes are the professional mechanosensors of bone. A strain-derived fluid flow through the lacuno-canalicular porosity seems to mechanically activate them, resulting in the production of signalling molecules such as nitric oxid...

Connexin 43 (Cx43) mediates osteocyte communication with other cells and with the extracellular milieu and regulates osteoblastic cell signaling and gene expression. We now report that mice lacking Cx43 in osteoblasts/osteocytes or only in osteocytes (Cx43(ΔOt) mice) exhibit increased osteocyte apoptosis, endocortical resorption, and periosteal bone formation, resulting in higher marrow cavity ...

The inaccessibility of osteocytes due to their embedment in the calcified bone matrix in vivo has precluded direct demonstration that osteocytes use gap junctions as a means of intercellular communication. In this article, we report successfully isolating primary cultures of osteocytes from chick calvaria, and, using anti-connexin 43 immunocytochemistry, demonstrate gap junction distribution to...

Osteocytes are major bone cells that play a crucial role in maintaining the quality of and healing damage to bone tissue. The number of living osteocytes and canalicular networks declines in an age-dependent manner. However, the pathological effects of mitochondrial redox imbalances on osteocytes and bone metabolism have not been fully elucidated. We generated mice lacking mitochondrial superox...

Harold Frost first proposed the existence of several mechanical thresholds in bone, two of which determine whether bone is added to, or lost from, the skeleton. Recent evidence from bone biology helps elucidate the role of osteocytes in determining these mechanical thresholds. Specifically, when mechanical stimuli fall below the resorption threshold, osteocyte apoptosis occurs, followed by bone...