Magnetic Enhancement of Chondrogenic Differentiation of Mesenchymal Stem Cells

Abstract

Pulsed electromagnetic field therapy, or pulsed signal therapy, has shown efficacy in treating many illnesses, including knee osteoarthritis. Although the mechanism is not fully understood, magnetic therapy is broadly welcomed because of its safe and noninvasive nature. At the cellular and molecular level, remote control of the cell fate by the magnetic field also has profound applications in both basic science and translational research. Here we demonstrate the use of pulsed electromagnetic field, one of the most benign and noninvasive extracellular cues, as a novel method to control specific chondrogenic differentiation of mesenchymal stem cells (MSCs). Chondrogenesis of transplanted MSCs inside the joint is considered one of the future therapies to rebuild the damaged cartilage. Here we show that pulsed electromagnetic field promotes chondrogenic differentiation of MSCs, and such a promoting effect can be drastically enhanced by the combined use of a magnetic hydrogel as the cell growth matrix. The magnetic hydrogel, synthesized by chemical cross-linking of gelatin and β-cyclodextrin and by embedding Fe3O4 magnetic nanoparticles in the hydrogel network, supports adhesion, growth, and proliferation of MSCs. Pulsed electromagnetic field boosts chondrogenesis of MSCs grown on the magnetic hydrogel, manifested by enhanced toluidine blue staining; higher expression of collagen II protein; and upregulation of collagen II, aggrecan, and SOX9 genes. Therefore, our work presents a robust method for chondrogenesis of MSCs using magnetic field as the external cue.

Inorganic Nanoparticles Applied as Functional Therapeutics

“…[ 167b ] Similar to osteogenic differentiation, cartilage differentiation can be promoted by incorporating NPs into a scaffold. [ 29e,168 ] TiO 2 NPs enhance the scaffold by increasing the adhesion and proliferation of the attached cells and exhibiting antibacterial effects. [ 29e ] Fe 3 O 4 NPs also increase cell adhesion and proliferation in the scaffold.…”

“…Conjecturably, the mechanism of inducing chondrogenic differentiation may be due to enhanced cell–cell interaction and increased nutrient perfusion through a pulsed electromagnetic field. [ 168a ] In some cases, scaffolds produce a similar mechanical strength to in‐nature cartilage through CaCO 3 NPs to promote differentiation. [ 168b ] Cases based on NP‐induced improvement in cartilage through in vivo treatment have also been described.…”

Pulse electromagnetic fields enhance the repair of rabbit articular cartilage defects with magnetic nano-hydrogel

“…13,14 The magnetic hydrogel with magnetic elds and stem cells proved enhance chondrogenesis in our previous in vitro research. 15 In the study, we use the magnetically eld is designed to produce mechanical stimuli to MSCs, for promoting chondrogenic differentiation. Gelatin, b-cyclodextrin (b-CD), and magnetic nanoparticles (Fe 3 O 4 ) were incorporated to form magnetic nanocomposite hydrogel as internal respond material.…”

Carbon coated Nickel Nanoparticles in Polyacrylamide Ferrogels: Interaction with Polymeric Network and Impact on Swelling

“…One of the main advantages of ferrogels over traditional stimulus-responsive polymers is that they can be remotely activated by a non-contact force (magnetic field). This unique property makes ferrogels prospective advanced material in various fields such as drug delivery [6,7], soft robotics [8], tissue reconstruction [9,10] and environmental engineering [11,12].…”

“…Huang et al [9] reported about a hydrogel formed by gelatin and β-cyclodextrin with embedded magnetic Fe 3 O 4 nanoparticles for pulsed electromagnetic field therapy. Chondrogenesis of mesenchymal stem cells grown on a magnetic hydrogel was enhanced by a magnetic field.…”