The Multifaceted Osteoclast; Far and Beyond Bone Resorption

Abstract

The accepted function of the bone resorbing cell, osteoclast, has been linked to bone remodeling and pathological osteolysis. Emerging evidence points to novel functions of osteoclasts in controlling bone formation and angiogenesis. Thus, while the concept of a "clastokine" with the potential to regulate osteogenesis during remodeling did not come as a surprise, new evidence provided unique insight into the mechanisms underlying osteoclastic control of bone formation. The question still remains as to whether osteoclast precursors or a unique trap positive mononuclear cell, can govern any aspect of bone formation. The novel paradigm eloquently proposed by leaders in the field brings together the concept of clastokines and osteoclast precursor-mediated bone formation, potentially though enhanced angiogenesis. These fascinating advances in osteoclast biology have motivated this short review, in which we discuss these new roles of osteoclasts. J. Cell. Biochem. 117: 1753-1756, 2016. © 2016 Wiley Periodicals, Inc.

Functional Calcium Binding Peptides from Pacific Cod (Gadus macrocephalus) Bone: Calcium Bioavailability Enhancing Activity and Anti-Osteoporosis Effects in the Ovariectomy-Induced Osteoporosis Rat Model

“…Bone turnover (including bone formation and resorption phase) were regulated by the bone remodeling process, and any disturbance in this process will lead to osteopathic disease [ 24 , 41 ]. The postmenopausal osteoporosis was recognized as high bone turnover rate, which was characterized by the increased bone turnover markers [ 5 , 26 ].…”

“…Previous study reported that, in order to maintain the calcium homeostasis, the bone turnover process could be accelerated by a decrease of serum calcium content [ 35 , 41 ] and also sufficient calcium intestinal absorption is critical for reduction of bone turnover rate and alleviation of osteoporosis [ 2 ]. Our results indicated that CBP-Ca could significantly increase the intestinal absorption, bioavailability of calcium, and serum calcium, then decrease bone turnover rate, and thus ameliorate osteoporosis.…”

Angiogenesis stimulated by elevated PDGF-BB in subchondral bone contributes to osteoarthritis development

“…Osteoclasts are derived from bone marrow monocytes/macrophages. Under physiological conditions, monocytes/macrophages first commit to macrophage colony-stimulating factor receptor-positive osteoclast precursor cells and then differentiate into receptor activator of nuclear factor κB-positive (RANK + ) tartrate-resistant acid phosphatase (TRAP + ) mononuclear preosteoclasts and eventually fuse to form mature multinuclear osteoclasts (39)(40)(41)(42)(43)(44)(45). Serving as precursors for osteoclasts, preosteoclasts have limited bone-resorbing activity.…”

Neogambogic Acid Suppresses Receptor Activator of Nuclear Factor κB Ligand (RANKL)-Induced Osteoclastogenesis by Inhibiting the JNK and NF-κB Pathways in Mouse Bone Marrow-Derived Monocyte/Macrophages

“…Osteoclasts, which differentiate from osteoclast precursor cells and can fuse with peripheral mononuclear cells, are cells involved in bone resorption [ 15 ]. BMMs are considered to be osteoclast precursor cells and can differentiate into osteoclast-like multinucleated cells in vitro via the synergistic actions of RANKL and M-CSF [ 11 , 13 ].…”