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Parathyroid hormone regulates osterix and Runx2 mRNA expression predominantly through protein kinase A signaling in osteoblast-like cells

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Abstract

Runt-related transcription factor 2 (Runx2) and osterix are osteoblast-specific transcription factors essential for the development of osteoblastic cells and bone formation. PTH given intermittently has anabolic effects on bone; however, the exact role remains to be understood completely. The purpose of this study was both to investigate whether PTH regulates Runx2 as well as osterix expression and to identify the signaling used. Using RTPCR, we confirmed that PTH (1–34) regulated Runx2 and osterix mRNA expression, in rat osteoblast-like cell line UMR 106, in a dose- and time-dependent manner. PTH in low concentrations stimulated both Runx2 and osterix mRNA expression while that in high concentrations did not. Forskolin, an adenylate cyclase activator, also enhanced Runx2 and osterix transcription, and the stimulatory effects of PTH and forskolin were blocked by the pre-treatment of thecells with H-89, a protein kinase A (PKA) inhibitor. In contrast, the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) had no effect on Runx2 transcription, but induced an increase in osterix mRNA level at the concentration of 500 nMat 12 h after treatment. Moreover, pre-treatment of the cells with calphostin C, a PKC-specific inhibitor, reduced the increase in osterix transcripts enhanced by PTH and PMA 12 h after treatment. However, these inhibitory effects were not sustained for longer terms. These observations demonstrate that PTH stimulates Runx2 and osterix expression in vitro, at least in part, at transcriptional level. Induction of Runx2 mRNA is mediated through the activation of cAMP/PKA signal transduction. In the case of osterix, although the increase in mRNA level is predominantly mediated via cAMP/PKA signaling, PKC activation might also be involved in this process.

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References

  1. Frolik CA, Black EC, Cain RL, et al. Anabolic and catabolic bone effects of human parathyroid hormone (1–34) are predicted by duration of hormone exposure. Bone 2003, 33: 372–9.

    Article  CAS  PubMed  Google Scholar 

  2. Locklin RM, Khosla S, Turner RT, Riggs BL. Mediators of the biphasic responses of bone to intermittent and continuously administered parathyroid hormone. J Cell Biochem 2003, 89: 180–90.

    Article  CAS  PubMed  Google Scholar 

  3. Demiralp B, Chen HL, Koh AJ, Keller ET, McCauley LK. Anabolic actions of parathyroid hormone during bone growth are dependent on c-fos. Endocrinology 2002, 143: 4038–47.

    Article  CAS  PubMed  Google Scholar 

  4. Tsingotjidou A, Nervina JM, Pham L, Bezouglaia O, Tetradis S. Parathyroid hormone induces RGS-2 expression by a cyclic adenosine 3′,5′-monophosphate-mediated pathway in primary neonatal murine osteoblasts. Bone 2002, 30: 677–84.

    Article  CAS  PubMed  Google Scholar 

  5. Bikle DD, Sakata T, Leary C, et al. Insulin-like growth factor I is required for the anabolic actions of parathyroid hormone on mouse bone. J Bone Miner Res 2002, 17: 1570–8.

    Article  CAS  PubMed  Google Scholar 

  6. Yamaguchi M, Ogata N, Shinoda Y, et al. Insulin receptor substrate-1 is required for bone anabolic function of parathyroid hormone in mice. Endocrinology 2005, 146: 2620–8.

    Article  CAS  PubMed  Google Scholar 

  7. Banerjee C, McCabe LR, Choi J-Y, et al. Runt homology domain proteins in osteoblast differentiation: AML3/CBFA1 is a major component of a bone specific complex. J Cell Biochem 1997, 66: 1–8.

    Article  CAS  PubMed  Google Scholar 

  8. Ducy P, Zhang R, Geoffroy V, Ridall AL, Karsenty G. Osf2/ Cbfa1: a transcriptional activator of osteoblast differentiation. Cell 1997, 89: 747–54.

    Article  CAS  PubMed  Google Scholar 

  9. Komori T, Yagi H, Nomura S, et al. Targeted disruption of Cbfa1 results in a complete lack of bone formation owing to maturational arrest of osteoblasts. Cell 1997, 89: 755–64.

    Article  CAS  PubMed  Google Scholar 

  10. Paredes R, Arriagada G, Cruzat F, et al. Bone-specific transcription factor Runx2 interacts with the 1alpha,25-di-hydroxyvitamin D3 receptor to up-regulate rat osteocalcin gene expression in osteoblastic cells. Mol Cell Biol 2004, 24: 8847–61.

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  11. Zheng H, Guo Z, Ma Q, Jia H, Dang G. Cbfa1/osf2 transduced bone marrow stromal cells facilitate bone formation in vitro and in vivo. Calcif Tissue Int 2004, 74: 194–203.

    Article  CAS  PubMed  Google Scholar 

  12. Sato M, Morii E, Komori T, et al. Transcriptional regulation of osteopontin gene in vivo by PEBP2alphaA/CBFA1 and ETS1 in the skeletal tissues. Oncogene 1998, 17: 151 7–25.

    Google Scholar 

  13. Byers BA, Pavlath GK, Murphy TJ, Karsenty G, Garcia AJ. Cell-type-dependent up-regulation of in vitro mineralization after overexpression of the osteoblast-specific transcription factor Runx2/Cbfal. J Bone Miner Res 2002, 17: 1931–44.

    Article  CAS  PubMed  Google Scholar 

  14. Nakashima K, Zhou X, Kunkel G, et al. The novel zinc finger-containing transcription factor osterix is required for osteoblast differentiation and bone formation. Cell 2002, 108: 17–29.

    Article  CAS  PubMed  Google Scholar 

  15. Jiang D, Franceschi RT, Boules H, Xiao G. Parathyroid hormone induction of the osteocalcin gene. Requirement for an osteoblast-specific element 1 sequence in the promoter and involvement of multiple-signaling pathways. J Biol Chem 2004, 279: 5329–37.

    CAS  Google Scholar 

  16. Winchester SK, Bloch SR, Fiacco GJ, Partridge NC. Regulation of expression of collagenase-3 in normal, differentiating rat osteoblasts. J Cell Physiol 1999, 181: 479–88.

    Article  CAS  PubMed  Google Scholar 

  17. Locklin RM, Khosla S, Turner RT, Riggs BL. Mediators of the biphasic responses of bone to intermittent and continuously administered parathyroid hormone. J Cell Biochem 2003, 89: 180–90.

    Article  CAS  PubMed  Google Scholar 

  18. Selvamurugan N, Pulumati MR, Tyson DR, Partridge NC. Parathyroid hormone regulation of the rat collagenase-3 promoter by protein kinase A-dependent transactivation of core binding factor alpha1. J Biol Chem 2000, 275: 5037–42.

    Article  CAS  PubMed  Google Scholar 

  19. Tai G, Polak JM, Bishop AE, Christodoulou I, Buttery LD. Differentiation of osteoblasts from murine embryonic stem cells by overexpression of the transcriptional factor osterix. Tissue Eng 2004, 10: 1456–66.

    Article  CAS  PubMed  Google Scholar 

  20. Liu W, Toyosawa S, Furuichi T, et al. Overexpression of Cbfa1 in osteoblasts inhibits osteoblast maturation and causes osteopenia with multiple fractures. J Cell Biol 2001, 155: 157–66.

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  21. Geoffroy V, Kneissel M, Fournier B, Boyde A, Matthias P. High bone resorption in adult aging transgenic mice over-expressing Cbfa1/Runx2 in cells of the osteoblastic lineage. Mol Cell Biol 2002, 22: 6222–33.

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  22. Tanaka S, Sakai A, Tanaka M, et al. Skeletal unloading alleviates the anabolic action of intermittent PTH(1–34) in mouse tibia in association with inhibition of PTH-induced increase in c-fos mRNA in bone marrow cells. J Bone Miner Res 2004, 19: 1813–20.

    Article  CAS  PubMed  Google Scholar 

  23. Celil AB, Hollinger JO, Campbell PG. Osx transcriptional regulation is mediated by additional pathways to BMP2/ Smad signaling. J Cell Biochem. 2005, 95: 518–28.

    Article  CAS  PubMed  Google Scholar 

  24. Lee MH, Kwon TG, Park HS, Wozney JM, Ryoo HM. BMP-2-induced Osterix expression is mediated by Dlx5 but is independent of Runx2. Biochem Biophys Res Commun 2003, 309: 689–94.

    Article  CAS  PubMed  Google Scholar 

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Correspondence to B. L. Wang PhD.

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Wang, B.L., Dai, C.L., Quan, J.X. et al. Parathyroid hormone regulates osterix and Runx2 mRNA expression predominantly through protein kinase A signaling in osteoblast-like cells. J Endocrinol Invest 29, 101–108 (2006). https://doi.org/10.1007/BF03344081

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