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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 14, 2014

Thyroid hormone and retinoic acid induce the synthesis of insulin-like growth factor-binding protein-4 in mouse

H Glantschnig1, F Varga, K Klaushofer

  • 1Ludwig Boltzmann Institute of Osteology, Fourth Medical Department, Hanusch-Hospital, Vienna, Austria.

Endocrinology
|January 1, 1996
PubMed

Insights

Thyroid hormone (T3) and retinoic acid stimulate insulin-like growth factor-binding protein-4 (IGFBP-4) mRNA transcription in osteoblasts. This increases IGFBP-4 secretion, potentially inhibiting osteoblast proliferation.

Area of Science:

  • Molecular Endocrinology
  • Gene Regulation
  • Osteoblast Biology

Background:

  • Thyroid hormone (T3) regulates gene transcription in various cell types.
  • Osteoblasts are crucial for bone metabolism and are influenced by hormonal signaling.

Purpose of the Study:

  • To identify genes regulated by thyroid hormone in osteoblasts.
  • To investigate the effect of T3 and retinoic acid on insulin-like growth factor-binding protein-4 (IGFBP-4) expression and secretion in osteoblasts.

Main Methods:

  • Subtractive hybridization to identify differentially expressed mRNAs.
  • cDNA sequencing and Northern blot analysis to characterize gene expression.
  • Screening of a mouse genomic library to isolate the IGFBP-4 gene.
  • Western immunoblotting to assess protein levels.

Main Results:

  • Identified and isolated the mouse IGFBP-4 gene.
  • Observed significant up-regulation of IGFBP-4 mRNA by T3 and retinoic acid in osteoblasts.
  • Demonstrated increased IGFBP-4 protein secretion into the medium.
  • Showed that T3 and retinoic acid reduce osteoblast DNA content, indicating antiproliferative effects.

Conclusions:

  • Thyroid hormone and retinoic acid stimulate IGFBP-4 gene transcription in osteoblasts.
  • Increased IGFBP-4 secretion may mediate the antiproliferative effects of these hormones on osteoblasts.

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