Advancements in tissue engineering and biomaterial development have the potential to provide a scalable solution to the problem of large‐volume skeletal muscle defects. Previous research on the development of scaffolds for skeletal muscle regeneration has focused on strategies for increasing conductivity, which has improved satellite cell attachment and differentiation. However, these strategies usually increase scaffold stiffness, which some studies suggest may be detrimental to myoblast development. In this study, the polymers polypyrrole (PPy) and polycaprolactone (PCL) were synthesized together into a copolymer (PPy–PCL) designed to increase scaffold conductivity without significantly influencing stiffness. Different scaffold groups were fabricated via electrospinning, characterized, and assessed for their suitability for myoblast proliferation and differentiation. The groups included an aligned and random iteration of pure PCL, 10% PPy–PCL, 20% PPy–PCL, and 40% PPy–PCL. Only the 40% PPy–PCL group had a measureable conductivity, and the addition of PPy–PCL had no significant effect on the stiffness of the scaffolds. The PPy–PCL copolymer significantly increased the attachment of C2C12 myoblasts as compared to pure PCL scaffolds, but the concentration of PPy–PCL did not significantly alter cell attachment. In addition, scaffolds with PPy–PCL promoted myoblast differentiation to a greater extent than scaffolds made of PCL as measured by fusion index and number of nuclei per myotube. Aligned scaffolds were superior to random scaffolds in almost all measures. These results suggest that conductivity may not be the key factor in improving skeletal muscle scaffolds. Instead, cell attachment and aligned guidance cues may have a greater impact on myoblast differentiation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 220–231, 2019.
Graphene, owing to its inherent chemical inertness, biocompatibility, and mechanical flexibility, has great potential in guiding cell behaviors such as adhesion and differentiation. However, due to the two-dimensional (2D) nature of graphene, the microfabrication of graphene into micro/nanoscale patterns has been widely adopted for guiding cellular assembly. In this study, we report crumpled graphene, i.e., monolithically defined graphene with a nanoscale wavy surface texture, as a tissue engineering platform that can efficiently promote aligned C2C12 mouse myoblast cell differentiation. We imparted out-of-plane, nanoscale crumpled morphologies to flat graphene via compressive strain-induced deformation. When C2C12 mouse myoblast cells were seeded on the uniaxially crumpled graphene, not only were the alignment and elongation promoted at a single-cell level but also the differentiation and maturation of myotubes were enhanced compared to that on flat graphene. These results demonstrate the utility of the crumpled graphene platform for tissue engineering and regenerative medicine for skeletal muscle tissues.
more » « less- NSF-PAR ID:
- 10154346
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Microsystems & Nanoengineering
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2055-7434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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