miR-125b inhibits osteoblastic differentiation by down-regulation of cell proliferation

https://doi.org/10.1016/j.bbrc.2008.01.073Get rights and content

Abstract

Although various microRNAs regulate cell differentiation and proliferation, no miRNA has been reported so far to play an important role in the regulation of osteoblast differentiation. Here we describe the role of miR-125b in osteoblastic differentiation in mouse mesenchymal stem cells, ST2, by regulating cell proliferation. The expression of miR-125b was time-dependently increased in ST2 cells, and the increase in miR-125b expression was attenuated in osteoblastic-differentiated ST2 cells induced by BMP-4. The transfection of exogenous miR-125b inhibited proliferation of ST2 cells and caused inhibition of osteoblastic differentiation. In contrast, when the endogenous miR-125b was blocked by transfection of its antisense RNA molecule, alkaline phosphatase activity after BMP-4 treatment was elevated. These results strongly suggest that miR-125b is involved in osteoblastic differentiation through the regulation of cell proliferation.

Section snippets

Materials and methods

Cell culture. ST2 cells were obtained from the RIKEN BioResource Center (BRC, Tsukuba, Japan) and cultured according to the protocols supplied by BRC (RPMI1640 supplemented with 10% fetal bovine serum (FBS)).

Osteoblastic differentiation. Osteoblastic differentiation was induced by changing to media containing 10% FBS supplemented with 100 ng/ml BMP-4 (R&D Systems, Minneapolis, MN, USA).

Alkaline phosphatase staining and measurement. Cells were fixed with 10% formalin for 20 min followed by 1 min

Increase in miR-125b expression is attenuated during osteoblastic differentiation

To determine the expression pattern of miR-125b during osteoblastic differentiation in ST2 cells, real-time RT-PCR was performed with the miRNA measurement protocol. As shown in Fig. 1, miR-125b expression was increased within 6 days in the cells that proliferated naturally without osteoblastic induction by BMP-4, suggesting that miR-125b may be involved in proliferation of ST2 cells. As a previous report showed that miR-125b has a negative effect on cell proliferation in cancer-related cells

Discussion

miRNAs have been reported to be involved in several important biological events, such as cell differentiation and proliferation. Although miRNAs are known to act as regulators in the differentiation of skeletal muscle, granulopoiesis and adipogenesis, there have been no reports so far that describe osteoblastogenesis-regulating miRNAs. Here, we reported details of miR-125b, a miRNA that regulates osteoblastic differentiation through the regulation of cell proliferation. We analyzed the function

Acknowledgments

We thank Shino Okumura and Megumi Otsu for technical assistance. We also thank Hiroyoshi Iseki, Hidemasa Bono, Yutaka Nakachi, Itoshi Nikaido, Shigeki Arai, and Riki Kurokawa for helpful discussion. This work was supported by grants of the Genome Network Project from the Ministry of Education, Culture, Sports, Science and Technology of Japan to Y.O., and also in part by the Ministry of Education, Culture, Sports, Science and Technology of Japan, and in particular by a Ministry Grant to Saitama

References (25)

  • T. Sugatani et al.

    MicroRNA-223 is a key factor in osteoclast differentiation

    J. Cell Biochem.

    (2007)
  • Y. Hayashita et al.

    A polycistronic microRNA cluster, miR-17-92, is overexpressed in human lung cancers and enhances cell proliferation

    Cancer Res.

    (2005)
  • Cited by (273)

    • Huogu injection alleviates SONFH by regulating adipogenic differentiation of BMSCs via targeting the miR-34c-5p/MDM4 pathway

      2022, Gene
      Citation Excerpt :

      Besides the pro-adipogenic roles mentioned above, miRNAs are vital in regulating the osteogenic differentiation of BMSCs (Wang et al., 2015). For instance, miRNA-125b (Mizuno et al., 2008), miRNA-141 (Itoh et al., 2009) and miRNA-200a (Itoh et al., 2009) promoted osteoblast differentiation via the bone morphogenic protein (BMP) pathway. Additionally, miRNA-27 (Wang and Xu, 2010), miRNA-29a (Kapinas et al., 2010), and miRNA-29b (Li et al., 2009) promoted the osteoblast differentiation of BMSCs by the activation of the Wnt pathway.

    • Comparative microRNAs expression profiles analysis during embryonic development of common carp, Cyprinus carpio

      2021, Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics
    View all citing articles on Scopus
    1

    Present address: Antibiotics Laboratory, RIKEN, 2-1 Hirosawa, Wako City, Saitama 351-0198, Japan.

    2

    Present address: Nano Medical Engineering Laboratory, RIKEN, 2-1 Hirosawa, Wako City, Saitama 351-0198, Japan.

    View full text