Introduction: Children with cerebral palsy (CP) and acquired brain injury (ABI) commonly develop muscle contractures with advancing age. An underlying growth defect contributing to skeletal muscle contracture formation in CP/ABI has been suggested.
Methods: The biceps muscles of children and adolescents with CP/ABI (n = 20) and typically developing controls (n = 10) were investigated. We used immunohistochemistry, quantitative real-time polymerase chain reaction, and Western blotting to assess gene expression relevant to growth and size homeostasis.
Results: Classical pro-inflammatory cytokines and genes involved in extracellular matrix (ECM) production were elevated in skeletal muscle of children with CP/ABI. Intramuscular collagen content was increased and satellite cell number decreased and this was associated with reduced levels of RNA polymerase I transcription factors, 45s pre-rRNA and 28S rRNA.
Discussion: The present study provides novel data suggesting a role for pro-inflammatory cytokines and reduced ribosomal production in the development/maintenance of muscle contractures, possibly underlying stunted growth and perimysial ECM expansion. Muscle Nerve 58: 277-285, 2018.
Keywords: cerebral palsy; cytokine; extracellular matrix; ribosome biogenesis; skeletal muscle.
© 2018 Wiley Periodicals, Inc.