Roles of Chondrocytes in Endochondral Bone Formation and Fracture Repair.
The formation of the mandibular condylar cartilage (MCC) and its subchondral bone is an important but understudied topic in dental research. The current concept regarding endochondral bone formation postulates that most hypertrophic chondrocytes undergo programmed cell death prior to bone formation. Under this paradigm, the MCC and its underlying bone are thought to result from 2 closely linked but separate processes: chondrogenesis and osteogenesis. However, recent investigations using cell lineage tracing techniques have demonstrated that many, perhaps the majority, of bone cells are derived via direct transformation from chondrocytes. In this review, the authors will briefly discuss the history of this idea and describe recent studies that clearly demonstrate that the direct transformation of chondrocytes into bone cells is common in both long bone and mandibular condyle development and during bone fracture repair. The authors will also provide new evidence of a distinct difference in ossification orientation in the condylar ramus (1 ossification center) versus long bone ossification formation (2 ossification centers). Based on our recent findings and those of other laboratories, we propose a new model that contrasts the mode of bone formation in much of the mandibular ramus (chondrocyte-derived) with intramembranous bone formation of the mandibular body (non-chondrocyte-derived).
1 Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA.
R J
RJ
Hinton
1 Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA.
Y
Y
Jing
1 Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA.
J
J
Jing
1 Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA.
J Q
JQ
Feng
D000818:Animals; D019902:Chondrocytes / Q000502:physiology*; D017102:Fracture Healing / Q000502:physiology*; D050723:Fractures, Bone / Q000503:physiopathology; D006801:Humans; D010012:Osteogenesis / Q000502:physiology*
cartilage; cell transdifferentiation; osteoblast; osteocyte; osteogenesis; temporomandibular joint
J Anat. 1987 Apr;151:169-88
3308801
Proc Natl Acad Sci U S A. 2005 Oct 11;102(41):14665-70
16203988
Am J Anat. 1988 Jul;182(3):197-214
3213819
J Bone Miner Res. 2014;29(5):1269-82
24259230
PLoS One. 2014 Aug 14;9(8):e104638
25121501
Connect Tissue Res. 2014 Aug;55 Suppl 1:73-8
25158185
Cell Res. 2014 Oct;24(10):1266-9
25145361
J Dent Res. 2015 Dec;94(12 ):1668-75
26341973
J Endocrinol. 2011 Nov;211(2):109-21
21642379
Bone Miner. 1992 Oct;19(1):1-20
1422302
Genesis. 2009 Dec;47(12):805-14
19830818
J Anat. 2003 Aug;203(2):213-22
12924821
Clin Orthop Relat Res. 1977 Nov-Dec;(129):299-304
608290
Histochemistry. 1990;93(6):593-9
2184152
Biol Open. 2015 Apr 16;4(5):608-21
25882555
J Bone Joint Surg Br. 1997 May;79(3):483-6
9180333
Microsc Res Tech. 1998 Oct 15;43(2):191-204
9823004
Trans Eur Orthod Soc. 1971;:103-15
5293075
J Cell Biol. 1992 Apr;117(2):427-35
1560033
PLoS Genet. 2014 Dec 04;10(12):e1004820
25474590
Matrix Biol. 2008 Oct;27(8):693-9
18692570
J Craniofac Genet Dev Biol. 1988;8(3):253-64
3209687
Nat Cell Biol. 2014 Dec;16(12):1157-67
25419849
J Anat. 1999 Oct;195 ( Pt 3):321-9
10580848
J Cell Biochem. 1996 Jul;62(1):1-9
8836870
J Cell Biol. 1995 Oct;131(2):483-94
7593173
Proc Natl Acad Sci U S A. 2014 Aug 19;111(33):12097-102
25092332
Anat Rec. 1987 Nov;219(3):221-32
3425941
Nature. 2003 May 15;423(6937):332-6
12748651
Dev Biol. 2007 Mar 1;303(1):391-404
17204263