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Updated: Aug 5, 2026

Application of Retinoic Acid to Obtain Osteocytes Cultures from Primary Mouse Osteoblasts
07:13

Application of Retinoic Acid to Obtain Osteocytes Cultures from Primary Mouse Osteoblasts

Published on: May 13, 2014

Inhibition of human osteoblast marker gene expression by retinoids is mediated in part by insulin-like growth factor

T Yan1, J Wergedal, Y Zhou

  • 1Musculoskeletal Disease Center (151), J.L. Pettis Memorial Veterans' Medical Center, 11201 Benton St., Loma Linda, CA 92357, USA.

Growth Hormone & IGF Research : Official Journal of the Growth Hormone Research Society and the International IGF Research Society
|March 27, 2002
PubMed

Insights

All-trans-retinoic acid (atRA) uses insulin-like growth factor binding protein-6 (IGFBP-6) to inhibit osteoblast gene expression. Reducing IGFBP-6 levels blocks atRA's inhibitory effects on osteoblast activity.

Area of Science:

  • Endocrinology
  • Molecular Biology
  • Cell Biology

Background:

  • All-trans-retinoic acid (atRA) is known to affect osteoblast gene expression.
  • Insulin-like growth factor binding protein-6 (IGFBP-6) expression is increased by atRA in human osteoblasts.

Purpose of the Study:

  • To investigate if IGFBP-6 mediates the inhibitory effects of atRA on osteoblast phenotype.
  • To explore the role of IGFBP-6 in atRA-induced inhibition of osteoblast marker gene expression.

Main Methods:

  • Utilized an antisense RNA approach in stable human osteosarcoma SaOS-2 cells.
  • Generated cells expressing antisense IGFBP-6 RNA under basal and atRA-stimulated conditions.
  • Quantified IGFBP-6 mRNA and protein levels, and alkaline phosphatase (ALP) activity.

Main Results:

  • Antisense IGFBP-6 clones showed reduced IGFBP-6 mRNA and protein.
  • IGFBP-6 protein levels were inversely correlated with alkaline phosphatase (ALP) activity.
  • atRA's inhibitory effect on ALP activity was significantly diminished in IGFBP-6 antisense clones.

Conclusions:

  • atRA recruits IGFBP-6 to inhibit the human osteoblast phenotype.
  • IGFBP-6 plays a crucial role in mediating atRA's effects on osteoblast function.

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