Stochastic resonance is a method to improve the biosynthetic response of chondrocytes to mechanical stimulation

Abstract

Cellular mechanosensitivity is an important factor during the mechanical stimulation of tissue engineered cartilage. While the application of mechanical stimuli improves tissue growth and properties, chondrocytes also rapidly desensitize under prolonged loading thereby limiting its effectiveness. One potential method to mitigate load-induced desensitization is by superimposing noise on the loading waveforms ("stochastic resonance"). Thus, the purpose of this study was to investigate the effects of stochastic resonance on chondrocyte matrix metabolism. Chondrocyte-seeded agarose gels were subjected to dynamic compressive loading, with or without, superimposed vibrations of different amplitudes and frequency bandwidths. Changes in matrix biosynthesis were determined by radioisotope incorporation and subsequent effects on intracellular calcium signaling were evaluated by confocal microscopy. Although dependent on the duration of loading, superimposed vibrations improved cellular sensitivity to mechanical loading by further increasing matrix synthesis between 20-60%. Stochastic resonance also appeared to limit load-induced desensitization by maintaining sensitivity under desensitized loading conditions. While superimposed vibrations had little effect on the magnitude of intracellular calcium signaling, recovery of mechanosensitivity after stimulation was achieved at a faster rate suggesting that less time may be required between successive loading applications. Thus, stochastic resonance appears to be a valuable tool during the mechanical stimulation of cartilage constructs, even when suboptimal stimulation conditions are used. ß

Weak electric fields detectability in a noisy neural network

“…Intensive studies have revealed the enhanced effects of noise on weak signals transmission, transduction and detection, which is known as stochastic resonance (SR) (Gammaitoni et al 1998;Kanamaru et al 2001;Zhou et al 2003;Cubero et al 2007;Yu et al 2011;Weber and Waldman 2016). It is a phenomenon based on the cooperative effect between the stochastic dynamical system and the external forcing (Wiesenfeld and Jaramillo 1998).…”

Effects of Rolling-Sliding Mechanical Stimulation on Cartilage Preserved In Vitro

“…Different loading patterns (time/frequency/strength) may affect chondrocyte metabolism. 16,36 Research has demonstrated the beneficial effects of physiologic magnitudes of mechanical stimulation on the biochemical properties of chondrocytes. However, raising pressures above these physiologic levels has been shown to have limited or detrimental effects.…”

Hepatitis C Virus Modelling In Vitro and In Vivo

“…The first study explored the application of dynamic compression, vibration and stochastic resonance (combined dynamic compression with superimposed random vibration 11 ) applied to chondrocytes seeded in agarose constructs in a short-term culture. The agarose constructs were stimulated for 20 minutes after which they were analyzed for DNA accumulation as well as collagen and proteoglycan synthesis.…”

“…Weber & Waldman showed improved cellular sensitivity to mechanical loading and increased matrix synthesis between 20-60% over short-term culture. Stochastic resonance also limited the loadinduced desensitization by maintaining sensitivity under desensitized loading conditions 11 .…”