Research Paper Volume 12, Issue 6 pp 4727—4741

Metformin coordinates osteoblast/osteoclast differentiation associated with ischemic osteonecrosis

See-Hyoung Park 1, *, , Mi-Ae Kang 2, *, , Young Jae Moon 3, *, , Kyu Yun Jang 4, , Jung Ryul Kim 3, ,

  • 1 Department of Bio and Chemical Engineering, Hongik University, Sejong, Korea
  • 2 Department of Biological Science, Gachon University, Seongnam, Korea
  • 3 Department of Orthopaedic Surgery, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital and Research Institute for Endocrine Sciences, Jeonju, Korea
  • 4 Department of Pathology, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital and Research Institute for Endocrine Sciences, Jeonju, Korea
* Equal contribution

received: October 27, 2019 ; accepted: January 12, 2020 ; published: February 11, 2020 ;

https://doi.org/10.18632/aging.102796
How to Cite

Copyright © 2020 Park et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

In this study, we aimed to identify a candidate drug that can activate endogenous Angiopoietin 1 (Ang1) expression via drug repositioning as a pharmacological treatment for avascular osteonecrosis. After incubation with 821 drugs from the Food and Drug Administration (FDA)-approved drug library, Ang1 expression in U2OS cell culture media was examined by ELISA. Metformin, the first-line medication for treatment of type 2 diabetes, was selected as a candidate for in vitro and in vivo experimental evaluation. Ang1 was induced, and alkaline phosphatase activity was increased by metformin treatment in U2OS and MG63 cells. Wound healing and migration assay showed increased osteoblastic cell mobility by metformin treatment in U2OS and MG63 cells. Metformin upregulated expression of protein markers for osteoblastic differentiation in U2OS and MG63 cells but inhibited osteoclastic differentiation in Raw264.7 cells. Metformin (25 mg/kg) protected against ischemic necrosis in the epiphysis of the rat femoral head by maintaining osteoblast/osteocyte function and vascular density but inhibiting osteoclast activity in the necrotic femoral head. These findings provide novel insight into the specific biomarkers that are targeted and regulated by metformin in osteoblast differentiation and contribute to understanding the effects of these FDA-approved small-molecule drugs as novel therapeutics for ischemic osteonecrosis.

Abbreviations

Ang1: angiopoietin1; Ang2: angiopoietin2; INFH: ischemic necrosis of the femoral head; FDA: Food and Drug Administration; AMPK: 5' adenosine monophosphate-activated protein kinase; COL1A1: alpha-1 type I collagen; OC: osteocalcin; BSP: bone sialoprotein; OSX: osterix; TRAP: tartrate-resistant acid phosphatase; ALPL: alkaline phosphatase; DMP1: dentin matrix acidic phosphoprotein 1; μCT: micro-computed tomography; IL-6: interleukin 6; Iκbα: nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha; IKKβ: inhibitor of nuclear factor kappa-B kinase subunit beta; NFκB: nuclear factor kappa-light-chain-enhancer of activated B cells; H&E: hematoxylin and eosin; vWF: von Willebrand factor; BV: bone volume; Tb. N: trabecular number; Tb.Sp: trabecular separation; Tb.Th: trabecular thickness; TV: tissue volume; Po: porosity.