The discoveries that sex steroid receptors for estrogen [estrogen receptor (ER)], androgen [androgen receptor (AR)], and progesterone [progesterone receptor (PR)] are present in the bone-forming osteoblasts (OB) and bone-resorbing osteoclasts (OCL), and that these cells are targets for sex steroid action, have generated much excitement in the field of bone biology. The subsequent discoveries th...

Coupling is the process that links bone resorption to formation in a temporally and spatially coordinated manner within the remodeling cycle. In order to maintain skeletal integrity, it is of crucial importance that the amount of bone resorbed matches the amount of newly formed bone in each remodeling site. Although a number of different explanatory models have been developed, the mechanisms th...

Disuse by bed rest, limb immobilization or space flight causes rapid bone loss by arresting bone formation and accelerating bone resorption. This net bone loss increases the risk of fracture upon remobilization. Bone loss also occurs in hibernating ground squirrels, golden hamsters, and little brown bats by arresting bone formation and accelerating bone resorption. There is some histological ev...

The Arg-Gly-Asp (RGD)-binding integrin alpha(V)beta(3) is highly expressed on osteoclasts and has been proposed to mediate cell-matrix adhesion required for osteoclast-mediated bone resorption. Antagonism of this receptor should prevent stable osteoclast adhesion and thereby inhibit bone resorption. We have generated an orally bioavailable, nonpeptide RGD mimetic alpha(v)beta(3) antagonist, SB ...

Mestastatic prostate cancer cells (MPCCs) frequently metastasize to bone, which is a “favorite soil” for colonization and proliferation of MPCCs. Prostate cancer bone mestastasis is tightly associated with tumor-induced bone lesions, most commonly caused from the etiological imbalance between osteoblastic bone formation and osteoclastic bone resorption, and from the anti-tumor immune response. ...

Human recombinant transforming growth factor alpha (TGF alpha), which binds to the epidermal growth factor (EGF) receptor and causes several biological effects similar to those caused by EGF, was compared with murine EGF for its effects on a number of parameters of bone cell metabolism. TGF alpha stimulated bone resorption in two organ culture systems, the fetal rat long bone and neonatal mouse...

Methods Using dual–energy X ray absorptiometry and bone metabolism markers (bone formation marker; BAP, bone resorption marker; TRAP5b), the bone mineral density of lumbar and bilateral proximal femurs were studied in 41 AIS patients aged 10 to 20 years old, with a mean of 15.2±5.9 years old. Divided into two groups by levels of bone resorption marker (TRAP5b), BMD, BMI and age of menarche were...

Bone homeostasis is maintained through a delicate balance between osteoblastic bone formation and osteoclastic bone resorption [1, 2]. Bone mass is reduced by decrease in osteoblastic bone formation and increase in osteoclastic bone resorption. Numerous pathological processes have the capacity to disrupt this equilibrium leading to conditions where the rate of bone resorption outpaces the rate ...

Bone deposition and bone resorption are ongoing dynamic processes, constituting bone remodeling. Some bone tumors, such as osteosarcoma (OS), stimulate focal bone deposition. OS is the most common primary bone tumor in children and young adults. A complex network of genes regulates bone remodeling and alterations in its expression levels can influence the genesis and progression of bone disease...

Bone integrity is maintained throughout life via the homeostatic actions of bone cells, namely, osteoclasts, which resorb bone, and osteoblasts, which produce bone. Disruption of this balance in favor of osteoclast activation results in pathological bone loss, which occurs in conditions including osteoporosis, rheumatoid arthritis, primary bone cancer, and cancer metastasis to bone. Hypoxia als...