1. Insulin Modulates Myogenesis and Muscle Atrophy Resulting From Skin Scald Burn in Young Male Rats.
- Author
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Quintana HT, Baptista VIA, Lazzarin MC, Antunes HKM, Le Sueur-Maluf L, de Oliveira CAM, and de Oliveira F
- Subjects
- Animals, Blood Glucose analysis, Body Surface Area, Burns pathology, Burns physiopathology, Gene Expression drug effects, Insulin-Like Growth Factor I genetics, Male, Muscle Proteins genetics, Muscle, Skeletal chemistry, Muscle, Skeletal pathology, Muscle, Skeletal physiopathology, Muscular Atrophy etiology, Muscular Atrophy genetics, MyoD Protein analysis, Myogenin analysis, Paired Box Transcription Factors analysis, Rats, Rats, Wistar, SKP Cullin F-Box Protein Ligases genetics, Tripartite Motif Proteins genetics, Ubiquitin-Protein Ligases genetics, Burns complications, Insulin administration & dosage, Muscle Development drug effects, Muscular Atrophy prevention & control
- Abstract
Background: Burn injuries (BIs) due to scalding are one of the most common accidents among children. BIs greater than 40% of total body surface area are considered extensive and result in local and systemic response. We sought to assess morphological and myogenic mechanisms through both short- and long-term intensive insulin therapies that affect the skeletal muscle after extensive skin BI in young rats., Materials and Methods: Wistar rats aged 21 d were distributed into four groups: control (C), control with insulin (C + I), scald burn injury (SI), and SI with insulin (SI + I). The SI groups were submitted to a 45% total body surface area burn, and the C + I and SI + I groups received insulin (5 UI/Kg/d) for 4 or 14 d. Glucose tolerance and the homeostatic model assessment of insulin resistance index were determined. Gastrocnemius muscles were analyzed for histopathological, morphometric, and immunohistochemical myogenic parameters (Pax7, MyoD, and MyoG); in addition, the expression of genes related to muscle atrophy (MuRF1 and MAFbx) and its regulation (IGF-1) were also assessed., Results: Short-term treatment with insulin favored muscle regeneration by primary myogenesis and decreased muscle atrophy in animals with BIs, whereas the long-term treatment modulated myogenesis by increasing the MyoD protein. Both treatments improved histopathological parameters and secondary myogenesis by increasing the MyoG protein., Conclusions: Treatment with insulin benefits myogenic parameters during regeneration and modulates MuRF1, an important mediator of muscle atrophy., (Published by Elsevier Inc.)
- Published
- 2021
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