Substrate stiffness affects skeletal myoblast differentiationin vitro

Abstract

To maximize the therapeutic efficacy of cardiac muscle constructs produced by stem cells and tissue engineering protocols, suitable scaffolds should be designed to recapitulate all the characteristics of native muscle and mimic the microenvironment encountered by cells in vivo. Moreover, so not to interfere with cardiac contractility, the scaffold should be deformable enough to withstand muscle contraction. Recently, it was suggested that the mechanical properties of scaffolds can interfere with stem/progenitor cell functions, and thus careful consideration is required when choosing polymers for targeted applications. In this study, cross-linked poly-ε-caprolactone membranes having similar chemical composition and controlled stiffness in a supra-physiological range were challenged with two sources of myoblasts to evaluate the suitability of substrates with different stiffness for cell adhesion, proliferation and differentiation. Furthermore, muscle-specific and non-related feeder layers were prepared on stiff surfaces to reveal the contribution of biological and mechanical cues to skeletal muscle progenitor differentiation. We demonstrated that substrate stiffness does affect myogenic differentiation, meaning that softer substrates can promote differentiation and that a muscle-specific feeder layer can improve the degree of maturation in skeletal muscle stem cells.

Hybrid Organic-Inorganic Scaffolding Biomaterials for Regenerative Therapies

“…The local mechanical interactions between cells and their microenvironment regulate cell shape, organization and differentiation of the different tissues [95,96] as can be observed in (Fig. 5) [97][98][99][100][101][102][103][104][105][106][107]. This observation is true in the natural environment as well as in artificial 3D structures.…”

“…[4,[97][98][99][100][101][102][103][104][105][106][107] On the bottom, typical substrate materials used for cell culturing. Polyacrylamide (PAM); Polydimethylsiloxane (PDMS); Polystyrene (PS).…”

Focus on the interlude between topographic transition and cell response on shape-memory surfaces

“…One of the great advantages of PCL over other temperature-responsive polymers is that surface properties such as wettability and charge are independent of temperature. We have previously shown how mechanical properties of PCL influence cell behavior using MSCs [21], skeletal myoblasts [22], fibroblasts [20], and neonatal cardiomyocytes [23,24]. We have also fabricated shape-memory substrates from PCL because the crosslinked PCL offers reversible crystallizable regions that can fix a temporary shape and have dualshape capability, showing a shape memory effect [19].…”

Improving myoblast differentiation on electrospun poly(ε‐caprolactone) scaffolds

“…It has been reported that substrate stiffness affects skeletal myoblast differentiation. 38 Myoblasts differentiate optimally on softer substrates with tissue-like stiffness. 39 The thinner fibers are less structurally stiff and therefore more similar to tissue stiffness (elastic modulus of muscle tissue ~ 5-15 kPa) 40 than the thicker fibers.…”

“…This could be related to diminished cell proliferation or migration, both regulated by decorin. 38,50 This in turn affects the formation of myotubes causing less and thinner myotubes to be present in PCL scaffolds.…”