TY - JOUR
T1 - Hyaluronan is essential for the expansion of the cranial base growth plates
AU - Gakunga, P. T.
AU - Kuboki, Y.
AU - Opperman, L. A.
N1 - Copyright:
Copyright 2004 Elsevier Science B.V., Amsterdam. All rights reserved.
PY - 2000
Y1 - 2000
N2 - Exquisite control of chondrocyte function in the zone of hypertrophy results in expansive growth of cartilaginous growth plates, and is a prerequisite for normal skeletal lengthening. We hypothesize that hyaluronan-mediated hydrostatic pressure causes lacunae expansion in the zone of hypertrophy; an important mechanism in cartilaginous growth plate and associated skeletal expansion. The role of hyaluronan and CD44 in this mechanism was studied using organ culture of the bipolar cranial base synchondroses. Hyaluronan was present in the hypertrophic zones, pericellular to the hypertrophic chondrocytes, while no hyaluronan was detected in the resting, proliferating and maturing zones. This localization of hyaluronan was associated with increased lacunae size, suggesting that chondrocytes deposit and retain pericellular hyaluronan as they mature. In comparison, Toluidine Blue staining was associated with the territorial matrix. Hyaluronidase, the hyaluronan-degrading enzyme, and CD44, the receptor for hyaluronan which also participates in the uptake and degradation of hyaluronan, were co-localized within the zone of ossification. This pattern of expression suggests that cells in the early zone of ossification internalize and degrade hyaluronan through a CD44-mediated mechanism. Treatment of the cultured segments with either Streptomyces hyaluronidase or hyaluronan hexasaccharides inhibited lacunae expansion. These observations demonstrate that hyaluronan-mediated mechanisms play an important role in controlling normal skeletal lengthening.
AB - Exquisite control of chondrocyte function in the zone of hypertrophy results in expansive growth of cartilaginous growth plates, and is a prerequisite for normal skeletal lengthening. We hypothesize that hyaluronan-mediated hydrostatic pressure causes lacunae expansion in the zone of hypertrophy; an important mechanism in cartilaginous growth plate and associated skeletal expansion. The role of hyaluronan and CD44 in this mechanism was studied using organ culture of the bipolar cranial base synchondroses. Hyaluronan was present in the hypertrophic zones, pericellular to the hypertrophic chondrocytes, while no hyaluronan was detected in the resting, proliferating and maturing zones. This localization of hyaluronan was associated with increased lacunae size, suggesting that chondrocytes deposit and retain pericellular hyaluronan as they mature. In comparison, Toluidine Blue staining was associated with the territorial matrix. Hyaluronidase, the hyaluronan-degrading enzyme, and CD44, the receptor for hyaluronan which also participates in the uptake and degradation of hyaluronan, were co-localized within the zone of ossification. This pattern of expression suggests that cells in the early zone of ossification internalize and degrade hyaluronan through a CD44-mediated mechanism. Treatment of the cultured segments with either Streptomyces hyaluronidase or hyaluronan hexasaccharides inhibited lacunae expansion. These observations demonstrate that hyaluronan-mediated mechanisms play an important role in controlling normal skeletal lengthening.
KW - Chondrocyte hypertrophy
KW - Cranial base synchondrosis
KW - Craniofacial growth and development
KW - Hyaluronan
UR - http://www.scopus.com/inward/record.url?scp=0033778401&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033778401&partnerID=8YFLogxK
M3 - Article
C2 - 11100735
AN - SCOPUS:0033778401
VL - 20
SP - 53
EP - 63
JO - Journal of Craniofacial Genetics and Developmental Biology
JF - Journal of Craniofacial Genetics and Developmental Biology
SN - 0270-4145
IS - 2
ER -