Abstract
In cell-based therapies for cartilage lesions, the main problem is still the formation of fibrous cartilage, caused by underlying de-differentiation processes ex vivo. Biophysical stimulation is a promising approach to optimize cell-based procedures and to adapt them more closely to physiological conditions. The occurrence of mechano-electrical transduction phenomena within cartilage tissue is physiological and based on streaming and diffusion potentials. The application of exogenous electric fields can be used to mimic endogenous fields and, thus, support the differentiation of chondrocytes in vitro. For this purpose, we have developed a new device for electrical stimulation of chondrocytes, which operates on the basis of capacitive coupling of alternating electric fields. The reusable and sterilizable stimulation device allows the simultaneous use of 12 cavities with independently applicable fields using only one main supply. The first parameter settings for the stimulation of human non-degenerative chondrocytes, seeded on collagen type I elastin-based scaffolds, were derived from numerical electric field simulations. Our first results suggest that applied alternating electric fields induce chondrogenic re-differentiation at the gene and especially at the protein level of human de-differentiated chondrocytes in a frequency-dependent manner. In future studies, further parameter optimizations will be performed to improve the differentiation capacity of human cartilage cells.
Highlights
One of the main tasks of articular cartilage is the absorption of mechanical loading and reduction of friction during joint movements
Articular cartilage is composed of two different phases: A fluid phase (65–80%), consisting mainly of water and dissolved inorganic ions, and a solid phase (20–35%), which is composed of different types of collagens, proteoglycans, and the embedded chondrocytes
Embedded chondrocytes are responsible for the synthesis and degradation of extracellular matrix (ECM) macromolecules, like collagen type (Col) II and glycosaminoglycans (GAGs)
Summary
One of the main tasks of articular cartilage is the absorption of mechanical loading and reduction of friction during joint movements. A fluid phase (65–80%), consisting mainly of water and dissolved inorganic ions, and a solid phase (20–35%), which is composed of different types of collagens, proteoglycans, and the embedded chondrocytes. It contains a small amount of lipids, phospholipids, noncollagenous proteins and glycoproteins [2,4,5]. Embedded chondrocytes are responsible for the synthesis and degradation of extracellular matrix (ECM) macromolecules, like collagen type (Col) II and glycosaminoglycans (GAGs) These macromolecules provide the cartilage tissue with dimensionality, elasticity, and strength to withstand mechanical loading [5,6]. Mechano-electrical transduction phenomena within the tissue occur physiologically and are based on streaming and diffusion potentials caused by mechanical loading of the micro-structured cartilage tissue [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
