[Anti-osteopenic effect of taurine: possible involvement of activated MEK-ERK-Cbfa1 signaling]

Nihon Yakurigaku Zasshi. 2002 Nov;120(1):114P-115P.
[Article in Japanese]


Previously we first noted that taurine (TR) has anti-osteopenic effect on low Ca diet-induced osteopenia in rats (1). Employing osteoblastic MC3T3-E1 cells, the mechanism of the anti-osteopenic effect was explored in vitro. TR (1 mM) was found to promote mineralization of extracellular matrices, without affecting alkaline phosphataase activity. Gel shift assay using 32P-labeled OSE2 (osteoblast-specific cis-element 2: the consensus sequence for Cbfa1, refer to 2) indicated that TR (1 mM) increased the nuclear localization of Cbfa1, just as TPH (1-34) (3,4) and bisphosphonates did (5). In addition, TR was found to stimulate ERK phosphorylation. PD98059, a MEK inhibitor, suppressed effects of TR on both Cbfa1 transactivation and ERK activation. The results strongly suggest that TR first activates intracellular MEK-ERK-Cbfa1 signaling system thereby promoting mineralization and finally leading to its bone anabolic action.

Publication types

  • English Abstract

MeSH terms

  • Animals
  • Calcification, Physiologic / drug effects*
  • Cell Differentiation / drug effects
  • Cells, Cultured
  • Core Binding Factor Alpha 1 Subunit
  • MAP Kinase Signaling System / drug effects
  • MAP Kinase Signaling System / physiology*
  • Neoplasm Proteins*
  • Osteoblasts / cytology*
  • Rats
  • Taurine / pharmacology*
  • Transcription Factors / metabolism
  • Transcription Factors / physiology*


  • Core Binding Factor Alpha 1 Subunit
  • Neoplasm Proteins
  • Transcription Factors
  • Taurine