Retinoid signaling regulates CTGF expression in hypertrophic chondrocytes with differential involvement of MAP kinases

Tsuyoshi Shimo, Eiki Koyama, Hiroki Sugito, Changshan Wu, Satoko Shimo, Maurizio Pacifici

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Retinoids are important for growth plate chondrocyte maturation, but their downstream effectors remain unclear. Recently, CTGF (CCN2) was found to regulate chondrocyte function, particularly in the hypertrophic zone. The goal of the study was to determine whether CTGF is a retinoid signaling effector molecule, how it is regulated, and how it acts. Introduction: Using a combination of in vivo and in vitro approaches, we carried out a series of studies at the cellular, biochemical, and molecular level to determine whether and how retinoid signaling is related to expression and function of connective tissue growth factor (CTGF) in chondrocyte maturation and endochondral ossification. Materials and Methods: Limbs of chick embryos in ovo were implanted with retinoic pan-antagonist RO 41-5253-filled beads, and phenotypic changes were assessed by in situ hybridization. CTGF gene expression and roles were tested in primary cultures of immature and hypertrophic chondrocytes. Cross-talk between retinoid signaling and other pathways was tested by determining endogenous levels of active ERK1/2 and p38 MAP kinases and phenotypic modulations exerted by specific antagonists of mitogen-activated protein (MAP) kinases and BMP signaling (Noggin). Results: Interference with retinoid signaling blocked expression of CTGF and other posthypertrophic markers in long bone anlagen in vivo and hypertrophic chondrocyte cultures, whereas all-trans-retinoic acid (RA) boosted CTGF expression and even induced it in immature proliferating cultures. Exogenous recombinant CTGF stimulated chondrocyte maturation, but failed to do so in presence of retinoid antagonists. Immunoblots showed that hypertrophic chondrocytes contained sizable levels of phosphorylated ERK1/2 and p38 MAP kinases that were dose- and time-dependently increased by RA treatment. Experimental ERK1/2 inhibition led to a severe drop in baseline and RA-stimulated CTGF expression, whereas p38 inhibition increased it markedly. These responses were gene-specific, because the opposite was seen with other hypertrophic chondrocyte genes such as collagen X and RA receptor γ(RARγ). Tests with Noggin showed that RA induction of CTGF expression was negatively influenced by BMP signaling, whereas induction of collagen X expression was BMP-dependent. Conclusions: Retinoids appear to have a preeminent role in controlling expression and function of CTGF in hypertrophic and posthypertrophic chondrocytes and do so with differential cooperation and intervention of MAP kinases and BMP signaling.

Original languageEnglish
Pages (from-to)867-877
Number of pages11
JournalJournal of Bone and Mineral Research
Volume20
Issue number5
DOIs
Publication statusPublished - May 2005

Fingerprint

Connective Tissue Growth Factor
Retinoids
Chondrocytes
Mitogen-Activated Protein Kinases
Tretinoin
p38 Mitogen-Activated Protein Kinases
Collagen
Retinoic Acid Receptors
Growth Plate
Chick Embryo
Osteogenesis
Genes
In Situ Hybridization
Extremities

Keywords

  • BMPs
  • Chondrocyte maturation
  • Connective tissue growth factor
  • Mitogen-activated protein kinases
  • Retinoid signaling
  • Skeletogenesis

ASJC Scopus subject areas

  • Surgery

Cite this

Retinoid signaling regulates CTGF expression in hypertrophic chondrocytes with differential involvement of MAP kinases. / Shimo, Tsuyoshi; Koyama, Eiki; Sugito, Hiroki; Wu, Changshan; Shimo, Satoko; Pacifici, Maurizio.

In: Journal of Bone and Mineral Research, Vol. 20, No. 5, 05.2005, p. 867-877.

Research output: Contribution to journalArticle

Shimo, Tsuyoshi ; Koyama, Eiki ; Sugito, Hiroki ; Wu, Changshan ; Shimo, Satoko ; Pacifici, Maurizio. / Retinoid signaling regulates CTGF expression in hypertrophic chondrocytes with differential involvement of MAP kinases. In: Journal of Bone and Mineral Research. 2005 ; Vol. 20, No. 5. pp. 867-877.
@article{7983ea58435f41378efbd812ed868609,
title = "Retinoid signaling regulates CTGF expression in hypertrophic chondrocytes with differential involvement of MAP kinases",
abstract = "Retinoids are important for growth plate chondrocyte maturation, but their downstream effectors remain unclear. Recently, CTGF (CCN2) was found to regulate chondrocyte function, particularly in the hypertrophic zone. The goal of the study was to determine whether CTGF is a retinoid signaling effector molecule, how it is regulated, and how it acts. Introduction: Using a combination of in vivo and in vitro approaches, we carried out a series of studies at the cellular, biochemical, and molecular level to determine whether and how retinoid signaling is related to expression and function of connective tissue growth factor (CTGF) in chondrocyte maturation and endochondral ossification. Materials and Methods: Limbs of chick embryos in ovo were implanted with retinoic pan-antagonist RO 41-5253-filled beads, and phenotypic changes were assessed by in situ hybridization. CTGF gene expression and roles were tested in primary cultures of immature and hypertrophic chondrocytes. Cross-talk between retinoid signaling and other pathways was tested by determining endogenous levels of active ERK1/2 and p38 MAP kinases and phenotypic modulations exerted by specific antagonists of mitogen-activated protein (MAP) kinases and BMP signaling (Noggin). Results: Interference with retinoid signaling blocked expression of CTGF and other posthypertrophic markers in long bone anlagen in vivo and hypertrophic chondrocyte cultures, whereas all-trans-retinoic acid (RA) boosted CTGF expression and even induced it in immature proliferating cultures. Exogenous recombinant CTGF stimulated chondrocyte maturation, but failed to do so in presence of retinoid antagonists. Immunoblots showed that hypertrophic chondrocytes contained sizable levels of phosphorylated ERK1/2 and p38 MAP kinases that were dose- and time-dependently increased by RA treatment. Experimental ERK1/2 inhibition led to a severe drop in baseline and RA-stimulated CTGF expression, whereas p38 inhibition increased it markedly. These responses were gene-specific, because the opposite was seen with other hypertrophic chondrocyte genes such as collagen X and RA receptor γ(RARγ). Tests with Noggin showed that RA induction of CTGF expression was negatively influenced by BMP signaling, whereas induction of collagen X expression was BMP-dependent. Conclusions: Retinoids appear to have a preeminent role in controlling expression and function of CTGF in hypertrophic and posthypertrophic chondrocytes and do so with differential cooperation and intervention of MAP kinases and BMP signaling.",
keywords = "BMPs, Chondrocyte maturation, Connective tissue growth factor, Mitogen-activated protein kinases, Retinoid signaling, Skeletogenesis",
author = "Tsuyoshi Shimo and Eiki Koyama and Hiroki Sugito and Changshan Wu and Satoko Shimo and Maurizio Pacifici",
year = "2005",
month = "5",
doi = "10.1359/JBMR.041235",
language = "English",
volume = "20",
pages = "867--877",
journal = "Journal of Bone and Mineral Research",
issn = "0884-0431",
publisher = "Wiley-Blackwell",
number = "5",

}

TY - JOUR

T1 - Retinoid signaling regulates CTGF expression in hypertrophic chondrocytes with differential involvement of MAP kinases

AU - Shimo, Tsuyoshi

AU - Koyama, Eiki

AU - Sugito, Hiroki

AU - Wu, Changshan

AU - Shimo, Satoko

AU - Pacifici, Maurizio

PY - 2005/5

Y1 - 2005/5

N2 - Retinoids are important for growth plate chondrocyte maturation, but their downstream effectors remain unclear. Recently, CTGF (CCN2) was found to regulate chondrocyte function, particularly in the hypertrophic zone. The goal of the study was to determine whether CTGF is a retinoid signaling effector molecule, how it is regulated, and how it acts. Introduction: Using a combination of in vivo and in vitro approaches, we carried out a series of studies at the cellular, biochemical, and molecular level to determine whether and how retinoid signaling is related to expression and function of connective tissue growth factor (CTGF) in chondrocyte maturation and endochondral ossification. Materials and Methods: Limbs of chick embryos in ovo were implanted with retinoic pan-antagonist RO 41-5253-filled beads, and phenotypic changes were assessed by in situ hybridization. CTGF gene expression and roles were tested in primary cultures of immature and hypertrophic chondrocytes. Cross-talk between retinoid signaling and other pathways was tested by determining endogenous levels of active ERK1/2 and p38 MAP kinases and phenotypic modulations exerted by specific antagonists of mitogen-activated protein (MAP) kinases and BMP signaling (Noggin). Results: Interference with retinoid signaling blocked expression of CTGF and other posthypertrophic markers in long bone anlagen in vivo and hypertrophic chondrocyte cultures, whereas all-trans-retinoic acid (RA) boosted CTGF expression and even induced it in immature proliferating cultures. Exogenous recombinant CTGF stimulated chondrocyte maturation, but failed to do so in presence of retinoid antagonists. Immunoblots showed that hypertrophic chondrocytes contained sizable levels of phosphorylated ERK1/2 and p38 MAP kinases that were dose- and time-dependently increased by RA treatment. Experimental ERK1/2 inhibition led to a severe drop in baseline and RA-stimulated CTGF expression, whereas p38 inhibition increased it markedly. These responses were gene-specific, because the opposite was seen with other hypertrophic chondrocyte genes such as collagen X and RA receptor γ(RARγ). Tests with Noggin showed that RA induction of CTGF expression was negatively influenced by BMP signaling, whereas induction of collagen X expression was BMP-dependent. Conclusions: Retinoids appear to have a preeminent role in controlling expression and function of CTGF in hypertrophic and posthypertrophic chondrocytes and do so with differential cooperation and intervention of MAP kinases and BMP signaling.

AB - Retinoids are important for growth plate chondrocyte maturation, but their downstream effectors remain unclear. Recently, CTGF (CCN2) was found to regulate chondrocyte function, particularly in the hypertrophic zone. The goal of the study was to determine whether CTGF is a retinoid signaling effector molecule, how it is regulated, and how it acts. Introduction: Using a combination of in vivo and in vitro approaches, we carried out a series of studies at the cellular, biochemical, and molecular level to determine whether and how retinoid signaling is related to expression and function of connective tissue growth factor (CTGF) in chondrocyte maturation and endochondral ossification. Materials and Methods: Limbs of chick embryos in ovo were implanted with retinoic pan-antagonist RO 41-5253-filled beads, and phenotypic changes were assessed by in situ hybridization. CTGF gene expression and roles were tested in primary cultures of immature and hypertrophic chondrocytes. Cross-talk between retinoid signaling and other pathways was tested by determining endogenous levels of active ERK1/2 and p38 MAP kinases and phenotypic modulations exerted by specific antagonists of mitogen-activated protein (MAP) kinases and BMP signaling (Noggin). Results: Interference with retinoid signaling blocked expression of CTGF and other posthypertrophic markers in long bone anlagen in vivo and hypertrophic chondrocyte cultures, whereas all-trans-retinoic acid (RA) boosted CTGF expression and even induced it in immature proliferating cultures. Exogenous recombinant CTGF stimulated chondrocyte maturation, but failed to do so in presence of retinoid antagonists. Immunoblots showed that hypertrophic chondrocytes contained sizable levels of phosphorylated ERK1/2 and p38 MAP kinases that were dose- and time-dependently increased by RA treatment. Experimental ERK1/2 inhibition led to a severe drop in baseline and RA-stimulated CTGF expression, whereas p38 inhibition increased it markedly. These responses were gene-specific, because the opposite was seen with other hypertrophic chondrocyte genes such as collagen X and RA receptor γ(RARγ). Tests with Noggin showed that RA induction of CTGF expression was negatively influenced by BMP signaling, whereas induction of collagen X expression was BMP-dependent. Conclusions: Retinoids appear to have a preeminent role in controlling expression and function of CTGF in hypertrophic and posthypertrophic chondrocytes and do so with differential cooperation and intervention of MAP kinases and BMP signaling.

KW - BMPs

KW - Chondrocyte maturation

KW - Connective tissue growth factor

KW - Mitogen-activated protein kinases

KW - Retinoid signaling

KW - Skeletogenesis

UR - http://www.scopus.com/inward/record.url?scp=17644402750&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=17644402750&partnerID=8YFLogxK

U2 - 10.1359/JBMR.041235

DO - 10.1359/JBMR.041235

M3 - Article

C2 - 15824860

AN - SCOPUS:17644402750

VL - 20

SP - 867

EP - 877

JO - Journal of Bone and Mineral Research

JF - Journal of Bone and Mineral Research

SN - 0884-0431

IS - 5

ER -