Functional cooperation between vitamin D receptor and Runx2 in vitamin D-induced vascular calcification

PLoS One. 2013 Dec 12;8(12):e83584. doi: 10.1371/journal.pone.0083584. eCollection 2013.

Abstract

The transdifferentiation of vascular smooth muscle cells (VSMCs) into osteoblast-like cells has been implicated in the context of vascular calcification. We investigated the roles of vitamin D receptor (Vdr) and runt-related transcription factor 2 (Runx2) in the osteoblastic differentiation of VSMCs in response to vitamin D3 using in vitro VSMCs cultures and in vivo in Vdr knockout (Vdr(-/-)) and Runx2 carboxy-terminus truncated heterozygous (Runx2(+/ΔC)) mice. Treatment of VSMCs with active vitamin D3 promoted matrix mineral deposition, and increased the expressions of Vdr, Runx2, and of osteoblastic genes but decreased the expression of smooth muscle myosin heavy chain in primary VSMCs cultures. Immunoprecipitation experiments suggested an interaction between Vdr and Runx2. Furthermore, silencing Vdr or Runx2 attenuated the procalcific effects of vitamin D3. Functional cooperation between Vdr and Runx2 in vascular calcification was also confirmed in in vivo mouse models. Vascular calcification induced by high-dose vitamin D3 was completely inhibited in Vdr(-/-) or Runx2(+/ΔC) mice, despite elevated levels of serum calcium or alkaline phosphatase. Collectively, these findings suggest that functional cooperation between Vdr and Runx2 is necessary for vascular calcification in response to vitamin D3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Density Conservation Agents / adverse effects*
  • Bone Density Conservation Agents / pharmacology
  • Cells, Cultured
  • Cholecalciferol / adverse effects*
  • Cholecalciferol / pharmacology
  • Core Binding Factor Alpha 1 Subunit / genetics
  • Core Binding Factor Alpha 1 Subunit / metabolism*
  • Mice
  • Mice, Knockout
  • Muscle, Smooth, Vascular / metabolism*
  • Muscle, Smooth, Vascular / pathology
  • Myocytes, Smooth Muscle / metabolism*
  • Myocytes, Smooth Muscle / pathology
  • Rats
  • Receptors, Calcitriol / genetics
  • Receptors, Calcitriol / metabolism*
  • Vascular Calcification* / chemically induced
  • Vascular Calcification* / genetics
  • Vascular Calcification* / metabolism
  • Vascular Calcification* / pathology

Substances

  • Bone Density Conservation Agents
  • Core Binding Factor Alpha 1 Subunit
  • Receptors, Calcitriol
  • Runx2 protein, mouse
  • Runx2 protein, rat
  • Cholecalciferol

Grant support

This research was supported by a grant of the Korean Health Technology R&D Project, Ministry of Health & Welfare, Republic of Korea (A111487), the WCU (World Class University) program (Grant no. R32-10064), and Basic Science Research Program (Grant no. 2012R1A6A3A01019166) through the National Research Foundation of Korea funded by the Korean Ministry of Education, Science and Technology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.