Mild burn amplifies the locomotive depression in demyelinated mice without muscle pathophysiological changes

PLoS One. 2024 Oct 7;19(10):e0308908. doi: 10.1371/journal.pone.0308908. eCollection 2024.

Abstract

Introduction: Patients with mild burns take most accounts, however, the impact of mild burns is less known. Nerve destruction leads to muscle atrophy. We posit that even mild burn injury could worsen demyelinated nerves related to muscle pathophysiological impairment.

Methods: Young adult C57BL/6 (male, n = 60) mice were randomly fed with either a 0.2% cuprizone diet or a regular rodent diet for 4 weeks. At week 5, all mice were then grouped into mild scald burn with 10% TBSA and sham injury groups. Mice received animal behavior tests and in situ muscle isometric force measurement before euthanasia for tissue collection.

Results: Total horizontal ambulation and vertical activity were significantly reduced in mice with mild burn injury (p<0.05). Mice with the cuprizone diet had significantly less time to fall than those with the regular diet on day 7 after burn (p<0.05). No significant difference was found in gastrocnemius tissue weight among the groups, nor muscle isometric tensions (all p>0.05). The cuprizone diet increased the maximal phosphorylating respiration in mice muscle mitochondria (p<0.05). The muscle protein expressions of caspase 3, Fbx-32, and Murf1 significantly increased in mice with the cuprizone diet 3 days after burn (p<0.05). The signal expression of S100B significantly increased in mice with the cuprizone diet, and its expression was even greater on day 7 after burn injury. (p<0.05).

Conclusion: The cuprizone diet-induced locomotion and cognitive disorders were amplified by the mild burn injury in mice, which is associated with muscle intracellular signal alterations. However, mild burn injury does not cause mouse muscle weight loss and function impairment. The potential risk of pre-existed neural impairment could be aware when patients encounter even small or mild burns.

MeSH terms

  • Animals
  • Burns* / complications
  • Burns* / pathology
  • Burns* / physiopathology
  • Cuprizone
  • Demyelinating Diseases / pathology
  • Demyelinating Diseases / physiopathology
  • Locomotion
  • Male
  • Mice
  • Mice, Inbred C57BL*
  • Mitochondria, Muscle / metabolism
  • Mitochondria, Muscle / pathology
  • Muscle Proteins / metabolism
  • Muscle, Skeletal* / metabolism
  • Muscle, Skeletal* / pathology
  • Muscle, Skeletal* / physiopathology
  • Muscular Atrophy / etiology
  • Muscular Atrophy / pathology
  • Muscular Atrophy / physiopathology
  • SKP Cullin F-Box Protein Ligases
  • Tripartite Motif Proteins / genetics
  • Tripartite Motif Proteins / metabolism
  • Ubiquitin-Protein Ligases / metabolism

Substances

  • Muscle Proteins
  • Cuprizone
  • Tripartite Motif Proteins
  • Ubiquitin-Protein Ligases
  • Trim63 protein, mouse
  • Fbxo32 protein, mouse
  • SKP Cullin F-Box Protein Ligases

Grants and funding

The study was partly supported by Remembering the 15 Research Education Endowment Fund at the Department of Surgery (C19584) at the University of Texas Medical Branch at Galveston. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.