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Abstract Skeletal muscle has a remarkable regeneration capacity to recover its structure and function after injury, except for the traumatic loss of critical muscle volume, called volumetric muscle loss (VML). Although many extremity VML models have been conducted, craniofacial VML has not been well‐studied due to unavailable in vivo assay tools. Here, this paper reports a wireless, noninvasive nanomembrane system that integrates skin‐wearable printed sensors and electronics for real‐time, continuous monitoring of VML on craniofacial muscles. The craniofacial VML model, using biopsy punch‐induced masseter muscle injury, shows impaired muscle regeneration. To measure the electrophysiology of small and round masseter muscles of active mice during mastication, a wearable nanomembrane system with stretchable graphene sensors that can be laminated to the skin over target muscles is utilized. The noninvasive system provides highly sensitive electromyogram detection on masseter muscles with or without VML injury. Furthermore, it is demonstrated that the wireless sensor can monitor the recovery after transplantation surgery for craniofacial VML. Overall, the presented study shows the enormous potential of the masseter muscle VML injury model and wearable assay tool for the mechanism study and the therapeutic development of craniofacial VML.
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A mouse model of volumetric muscle loss and therapeutic scaffold implantation
Skeletal myofibers naturally regenerate after damage; however, impaired muscle function can result in cases when a prominent portion of skeletal muscle mass is lost, for example, following traumatic muscle injury. Volumetric muscle loss can be modeled in mice using a surgical model of muscle ablation to study the pathology of volumetric muscle loss and to test experimental treatments, such as the implantation of acellular scaffolds, which promote de novo myogenesis and angiogenesis. Here we provide step-by-step instructions to perform full-thickness surgical ablation, using biopsy punches, and to remove a large volume of the tibialis anterior muscle of the lower limb in mice. This procedure results in a reduction in muscle mass and limited regeneration capacity; the approach is easy to reproduce and can also be applied to larger animal models. For therapeutic applications, we further explain how to implant bioscaffolds into the ablated muscle site. With adequate training and practice, the surgical procedure can be performed within 30 min.
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- Award ID(s):
- 2227614
- PAR ID:
- 10560634
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Protocols
- ISSN:
- 1754-2189
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41596-024-01059-y
