Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
Bonewald L. Osteocytes. In: Marcus R, editor. Osteoporosis, 3rd ed. Elsevier; 2008. p. 170–89.
Gu G, Nars M, Hentunen TA, et al. Isolated primary osteocytes express functional gap junctions in vitro. Cell Tissue Res. 2006;323(2):263–71. ArticlePubMed Google Scholar
Feng JQ, Ward LM, Liu S, et al. Loss of DMP1 causes rickets and osteomalacia and identifies a role for osteocytes in mineral metabolism. Nat Genet. 2006;38(11):1310–5. ArticlePubMedCAS Google Scholar
He G, George A. Dentin matrix protein 1 immobilized on type I collagen fibrils facilitates apatite deposition in vitro. J Biol Chem. 2004;279(12):11649–56. ArticlePubMedCAS Google Scholar
Ruchon AF, Tenenhouse HS, Marcinkiewicz M, et al. Developmental expression and tissue distribution of Phex protein: effect of the Hyp mutation and relationship to bone markers. J Bone Miner Res. 2000;15(8):1440–50. ArticlePubMedCAS Google Scholar
A gene (PEX) with homologies to endopeptidases is mutated in patients with X-linked hypophosphatemic rickets. The HYP Consortium. Nat Genet. 1995;11(2):130–6. Google Scholar
Fisher LW, Fedarko NS. Six genes expressed in bones and teeth encode the current members of the SIBLING family of proteins. Connect Tissue Res. 2003;44 Suppl 1:33–40. PubMedCAS Google Scholar
Rowe PS, Garrett IR, Schwarz PM, et al. Surface plasmon resonance (SPR) confirms that MEPE binds to PHEX via the MEPE-ASARM motif: a model for impaired mineralization in X-linked rickets (HYP). Bone. 2005;36(1):33–46. ArticlePubMedCAS Google Scholar
Gowen LC, Petersen DN, Mansolf AL, et al. Targeted disruption of the osteoblast/osteocyte factor 45 gene (OF45) results in increased bone formation and bone mass. J Biol Chem. 2003;278(3):1998–2007. ArticlePubMedCAS Google Scholar
Liu SG, Quarles LD. How fibroblast growth factor 23 works. J Am Soc Nephrol. 2007;18(6):1637–47. ArticlePubMedCAS Google Scholar
Liu S, Zhou J, Tang W, et al. Pathogenic role of Fgf23 in Hyp mice. Am J Physiol Endocrinol Metab. 2006;291(1):E38–49. ArticlePubMedCAS Google Scholar
Liu S, Guo R, Simpson LG, et al. Regulation of fibroblastic growth factor 23 expression but not degradation by PHEX. J Biol Chem. 2003;278(39):37419–26. ArticlePubMedCAS Google Scholar
Poole KE, van Bezooijen RL, Loveridge N, et al. Sclerostin is a delayed secreted product of osteocytes that inhibits bone formation. FASEB J. 2005;19(13):1842–4. PubMedCAS Google Scholar
Balemans W, Ebeling M, Patel N, et al. Increased bone density in sclerosteosis is due to the deficiency of a novel secreted protein (SOST). Hum Mol Genet. 2001;10(5):537–43. ArticlePubMedCAS Google Scholar
Li X, Ominsky MS, Niu QT, et al. Targeted deletion of the sclerostin gene in mice results in increased bone formation and bone strength. J Bone Miner Res. 2008;23(6):860–9. ArticlePubMed Google Scholar
Bodine PV, Vernon SK, Komm BS. Establishment and hormonal regulation of a conditionally transformed preosteocytic cell line from adult human bone. Endocrinology. 1996;137(11):4592–604. ArticlePubMedCAS Google Scholar
Kato Y, Boskey A, Spevak L, et al. Establishment of an osteoid preosteocyte-like cell MLO-A5 that spontaneously mineralizes in culture. J Bone Miner Res. 2001;16(9):1622–33. ArticlePubMedCAS Google Scholar
Kato Y, Windle JJ, Koop BA, et al. Establishment of an osteocyte-like cell line, MLO-Y4. J Bone Miner Res. 1997;12(12):2014–23. ArticlePubMedCAS Google Scholar
Rosser J, Bonewald LF. Studying osteocyte function using the cell lines MLO-Y4 and MLO-A5. Methods Mol Biol. 2012;816:67–81. ArticlePubMed Google Scholar
• Al-Dujaili SA, Lau E, Al-Dujaili H, et al. Apoptotic osteocytes regulate osteoclast precursor recruitment and differentiation in vitro. J Cell Biochem. 2011;112(9):2412–23. Describes an in vitro model used to study gene expression of MLO-Y4 cells undergoing apoptosis, and the subsequent effect on osteoclastogenesis. ArticlePubMedCAS Google Scholar
Zahm AM, Bucaro MA, Srinivas V, et al. Oxygen tension regulates preosteocyte maturation and mineralization. Bone. 2008;43(1):25–31. ArticlePubMedCAS Google Scholar
Genetos DC, Kephart CJ, Zhang Y, et al. Oscillating fluid flow activation of gap junction hemichannels induces ATP release from MLO-Y4 osteocytes. J Cell Physiol. 2007;212(1):207–14. ArticlePubMedCAS Google Scholar
Kwon RY, Temiyasathit S, Tummala P, et al. Primary cilium-dependent mechanosensing is mediated by adenylyl cyclase 6 and cyclic AMP in bone cells. FASEB J. 2010;24(8):2859–68. ArticlePubMedCAS Google Scholar
• Xia X, Kar R, Gluhak-Heinrich J, et al. Glucocorticoid-induced autophagy in osteocytes. J Bone Miner Res. 2010;25(11):2479–88. Demonstrates the effects of glucocorticoids on osteocytes in terms of autophagy and apoptosis. Proposes new mechanisms responsible for bone loss in patients receiving glucocorticoid therapy.. ArticlePubMedCAS Google Scholar
Plotkin LI, Aguirre JI, Kousteni S, et al. Bisphosphonates and estrogens inhibit osteocyte apoptosis via distinct molecular mechanisms downstream of extracellular signal-regulated kinase activation. J Biol Chem. 2005;280(8):7317–25. ArticlePubMedCAS Google Scholar
•• Batra N, Burra S, Siller-Jackson AJ, et al. Mechanical stress-activated integrin alpha5beta1 induces opening of connexin 43 hemichannels. Proc Natl Acad Sci USA. 2012;109(9):3359–64. Shows that mechanical perturbation or conformational activation of integrin α5β1 leads to the opening of the connexin 43 hemichannel, a potentially important pathway for cell-cell communication.. ArticlePubMedCAS Google Scholar
Heino TJ, Hentunen TA, Vaananen HK. Conditioned medium from osteocytes stimulates the proliferation of bone marrow mesenchymal stem cells and their differentiation into osteoblasts. Exp Cell Res. 2004;294(2):458–68. ArticlePubMedCAS Google Scholar
Tanaka-Kamioka K, Kamioka H, Ris H, et al. Osteocyte shape is dependent on actin filaments and osteocyte processes are unique actin-rich projections. J Bone Miner Res. 1998;13(10):1555–68. ArticlePubMedCAS Google Scholar
Cowin SC, Moss-Salentijn L, Moss ML. Candidates for the mechanosensory system in bone. J Biomech Eng. 1991;113(2):191–7. ArticlePubMedCAS Google Scholar
Weinbaum S, Cowin SC, Zeng Y. A model for the excitation of osteocytes by mechanical loading-induced bone fluid shear stresses. J Biomech. 1994;27(3):339–60. ArticlePubMedCAS Google Scholar
Skerry TM, Bitensky L, Chayen J, et al. Early strain-related changes in enzyme activity in osteocytes following bone loading in vivo. J Bone Miner Res. 1989;4(5):783–8. ArticlePubMedCAS Google Scholar
Dallas SL, Zaman G, Pead MJ, et al. Early strain-related changes in cultured embryonic chick tibiotarsi parallel those associated with adaptive modeling in vivo. J Bone Miner Res. 1993;8(3):251–9. ArticlePubMedCAS Google Scholar
Dodds RA, Ali N, Pead MJ, et al. Early loading-related changes in the activity of glucose 6-phosphate dehydrogenase and alkaline phosphatase in osteocytes and periosteal osteoblasts in rat fibulae in vivo. J Bone Miner Res. 1993;8(3):261–7. ArticlePubMedCAS Google Scholar
Gluhak-Heinrich J, Ye L, Bonewald LF, et al. Mechanical loading stimulates dentin matrix protein 1 (DMP1) expression in osteocytes in vivo. J Bone Miner Res. 2003;18(5):807–17. ArticlePubMedCAS Google Scholar
Verborgt O, Gibson GJ, Schaffler MB. Loss of osteocyte integrity in association with microdamage and bone remodeling after fatigue in vivo. J Bone Miner Res. 2000;15(1):60–7. ArticlePubMedCAS Google Scholar
Yang W, Lu Y, Kalajzic I, et al. Dentin matrix protein 1 gene cis-regulation: use in osteocytes to characterize local responses to mechanical loading in vitro and in vivo. J Biol Chem. 2005;280(21):20680–90. ArticlePubMedCAS Google Scholar
•• Cardoso L, Herman BC, Verborgt O, et al. Osteocyte apoptosis controls activation of intracortical resorption in response to bone fatigue. J Bone Miner Res. 2009;24(4):597–605. Demonstrates that osteocyte apoptosis is an obligatory step toward osteoclastogenesis in response to microdamage in cortical bone.. ArticlePubMedCAS Google Scholar
Zhang K, Barragan-Adjemian C, Ye L, et al. E11/gp38 selective expression in osteocytes: regulation by mechanical strain and role in dendrite elongation. Mol Cell Biol. 2006;26(12):4539–52. ArticlePubMedCAS Google Scholar
Ajubi NE, Klein-Nulend J, Nijweide PJ, et al. Pulsating fluid flow increases prostaglandin production by cultured chicken osteocytes–a cytoskeleton-dependent process. Biochem Biophys Res Commun. 1996;225(1):62–8. ArticlePubMedCAS Google Scholar
Wang L, Cowin SC, Weinbaum S, et al. Modeling tracer transport in an osteon under cyclic loading. Ann Biomed Eng. 2000;28(10):1200–9. ArticlePubMedCAS Google Scholar
Wang L, Wang Y, Han Y, et al. In situ measurement of solute transport in the bone lacunar-canalicular system. Proc Natl Acad Sci USA. 2005;102(33):11911–6. ArticlePubMedCAS Google Scholar
Squire JM, Chew M, Nneji G, et al. Quasi-periodic substructure in the microvessel endothelial glycocalyx: a possible explanation for molecular filtering? J Struct Biol. 2001;136(3):239–55. ArticlePubMedCAS Google Scholar
Burr DB, Martin RB, Schaffler MB, et al. Bone remodeling in response to in vivo fatigue microdamage. J Biomech. 1985;18(3):189–200. ArticlePubMedCAS Google Scholar
Burr DB, Forwood MR, Fyhrie DP, et al. Bone microdamage and skeletal fragility in osteoporotic and stress fractures. J Bone Miner Res. 1997;12(1):6–15. ArticlePubMedCAS Google Scholar
Bentolila V, Boyce TM, Fyhrie DP, et al. Intracortical remodeling in adult rat long bones after fatigue loading. Bone. 1998;23(3):275–81. ArticlePubMedCAS Google Scholar
Verborgt O, Tatton NA, Majeska RJ, et al. Spatial distribution of Bax and Bcl-2 in osteocytes after bone fatigue: complementary roles in bone remodeling regulation? J Bone Miner Res. 2002;17(5):907–14. ArticlePubMedCAS Google Scholar
Cheng Y, Deshmukh M, D’Costa A, et al. Caspase inhibitor affords neuroprotection with delayed administration in a rat model of neonatal hypoxic-ischemic brain injury. J Clin Invest. 1998;101(9):1992–9. ArticlePubMedCAS Google Scholar
Nicholson DW. From bench to clinic with apoptosis-based therapeutic agents. Nature. 2000;407(6805):810–6. ArticlePubMedCAS Google Scholar
•• Kennedy OD, Herman BC, Laudier DM, et al. Activation of resorption in fatigue-loaded bone involves both apoptosis and active pro-osteoclastogenic signaling by distinct osteocyte populations. Bone. 2012; doi: 10.1016/j.bone.2012.01.025. Demonstrates osteocyte expression of pro-osteoclastogenic factors by distinct cell populations in nearby sites of microdamage.
Nakashima T, Kobayashi Y, Yamasaki S, et al. Protein expression and functional difference of membrane-bound and soluble receptor activator of NF-kappaB ligand: modulation of the expression by osteotropic factors and cytokines. Biochem Biophys Res Commun. 2000;275(3):768–75. ArticlePubMedCAS Google Scholar
•• Nakashima T, Hayashi M, Fukunaga T, et al. Evidence for osteocyte regulation of bone homeostasis through RANKL expression. Nat Med. 2011;17(10):1231–4. Shows that purified osteocytes express RANKL and have the capacity to support osteoclastogenesis in vitro. Also shows osteocytes are a major source of RANKL in bone remodeling in vivo. ArticlePubMedCAS Google Scholar
•• Xiong J, Onal M, Jilka RL, et al. Matrix-embedded cells control osteoclast formation. Nat Med. 2011;17:1234–41. Uses a transgenic model with RANKL conditionally deleted to demonstrate that hypertrophic chondrocytes and osteocytes, both of which are embedded in matrix, are essential sources of the RANKL that controls mineralized cartilage resorption and bone remodeling, respectively. Article Google Scholar
Baron R, Tross R, Vignery A. Evidence of sequential remodeling in rat trabecular bone - morphology, dynamic histomorphometry, and changes during skeletal maturation. Anat Rec. 1984;208(1):137–45. ArticlePubMedCAS Google Scholar
Fisher M. The ischemic penumbra: identification, evolution and treatment concepts. Cerebrovasc Dis. 2004;17 Suppl 1:1–6. ArticlePubMed Google Scholar