Nanohydroxyapatite (nHAp) Doped with Iron Oxide Nanoparticles (IO), miR-21 and miR-124 Under Magnetic Field Conditions Modulates Osteoblast Viability, Reduces Inflammation and Inhibits the Growth of Osteoclast - A Novel Concept for Osteoporosis Treatment: Part 1

Int J Nanomedicine. 2021 May 18:16:3429-3456. doi: 10.2147/IJN.S303412. eCollection 2021.

Abstract

Purpose: Osteoporosis results in a severe decrease in the life quality of many people worldwide. The latest data shows that the number of osteoporotic fractures is becoming an increasing international health service problem. Therefore, a new kind of controllable treatment methods for osteoporotic fractures is extensively desired. For that reason, we have manufactured and evaluated nanohydroxyapatite (nHAp)-based composite co-doped with iron oxide (IO) nanoparticles. The biomaterial was used as a matrix for the controlled delivery of miR-21-5p and miR-124-3p, which have a proven impact on bone cell metabolism.

Methods: The nanocomposite Ca5(PO4)3OH/Fe3O4 (later called nHAp/IO) was obtained by the wet chemistry method and functionalised with microRNAs (nHAp/IO@miR-21/124). Its physicochemical characterization was performed using XRPD, FT-IR, SEM-EDS and HRTEM and SAED methods. The modulatory effect of the composite was tested in vitro using murine pre-osteoblasts MC3T3-E1 and pre-osteoclasts 4B12. Moreover, the anti-inflammatory effects of biomaterial were analysed using a model of LPS-treated murine macrophages RAW 264.7. We have analysed the cells' viability, mitochondria membrane potential and oxidative stress under magnetic field (MF+) and without (MF-). Moreover, the results were supplemented with RT-qPCR and Western blot assays to evaluate the expression profile for master regulators of bone metabolism.

Results: The results indicated pro-osteogenic effects of nHAp/IO@miR-21/124 composite enhanced by exposure to MF. The enhanced osteogenesis guided by nHAp/IO@miR-21/124 presence was associated with increased metabolism of progenitor cells and activation of osteogenic markers (Runx-2, Opn, Coll-1). Simultaneously, nanocomposite decreased metabolism and differentiation of pre-osteoclastic 4B12 cells accompanied by reduced expression of CaII and Ctsk. Obtained composite regulated viability of bone progenitor cells and showed immunomodulatory properties inhibiting the expression of inflammatory markers, ie, TNF-α, iNOs or IL-1β, in LPS-stimulated RAW 264.7 cells.

Conclusion: We have described for the first time a new concept of osteoporosis treatment based on nHAp/IO@miR-21/124 application. Obtained results indicated that fabricated nanocomposite might impact proper regeneration of osteoporotic bone, restoring the balance between osteoblasts and osteoclast.

Keywords: hydroxyapatite; nanocomposites; osteoblasts; osteoclasts; osteoporosis.

MeSH terms

  • 3T3 Cells
  • Animals
  • Cell Differentiation / genetics
  • Cell Proliferation / genetics
  • Cell Survival / genetics
  • Drug Carriers / chemistry
  • Durapatite / chemistry*
  • Inflammation / therapy
  • Magnetic Fields
  • Magnetic Iron Oxide Nanoparticles / chemistry*
  • Mice
  • MicroRNAs / chemistry*
  • MicroRNAs / genetics
  • Nanocomposites / chemistry
  • Osteoblasts / cytology*
  • Osteoblasts / pathology
  • Osteoclasts / cytology*
  • Osteoclasts / pathology
  • Osteogenesis / genetics
  • Osteoporosis / genetics
  • Osteoporosis / pathology*
  • Osteoporosis / therapy

Substances

  • Drug Carriers
  • MIRN21 microRNA, mouse
  • MicroRNAs
  • Mirn124 microRNA, mouse
  • Durapatite

Grants and funding

Financial support was obtained for the completion of the Harmonia 9 project titled “New, two-stage scaffolds based on calcium nanoapatite (nHAP) incorporated with iron nanotoxides (Fe2O3/Fe3O4) with the function of controlled release of miRNA in a static magnetic field for the regeneration of bone fractures in osteoporotic patients. (Grant No. UMO 2017/26/M/NZ5/01184)” The publication is financed under the Leading Research Groups support project from the subsidy increased for the period 2020–2025 in the amount of 2% of the subsidy referred to Art. 387 (3) of the Law of 20 July 2018 on Higher Education and Science, obtained in 2019.