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Updated: Sep 30, 2026
Analyzing Satellite Cell Function During Skeletal Muscle Regeneration by Cardiotoxin Injury and Injection of Self-delivering siRNA In Vivo
Published on: September 18, 2019
Changes in mass and performance in rabbit muscles after muscle damage with or without transplantation of primary
Ramzi Boubaker el Andalousi1, Paul-André Daussin, Jean-Paul Micallef
1UMR Différenciation cellulaire et Croissance, INRA, Montpellier, France.
Abstract:
Changes in morphology, metabolism, myosin heavy chain gene expression, and functional performances in damaged rabbit muscles with or without transplantation of primary satellite cells were investigated. For this purpose, we damaged bilaterally the fast muscle tibialis anterior (TA) with either 1.5 or 2.6 ml cardiotoxin 10(-5) M injections. Primary cultures of satellite cells were autotransplanted unilaterally 5 days after muscle degeneration. Two months postoperation, the masses of damaged TAs, with or without transplantation, were significantly larger than those of the controls. Furthermore, damaged transplanted muscles weighed significantly more than damaged muscles only. The increase in muscle mass was essentially due to increased fiber size. These results were independent of the quantity of cardiotoxin injected into the muscles. Maximal forces were similar in control and 2.6 ml damaged TAs with or without satellite cell transfer. In contrast, 1.5 ml damaged TAs showed a significant decrease in maximal forces that reached the level of controls after transplantation of satellite cells. Fatigue resistance was similar in control and 1.5 ml damaged TAs independently of satellite cell transfer. Fatigue index was significantly higher in 2.6 ml damaged muscles with or without cell transplantation. These changes could be explained in part by muscle metabolism, which shifted towards oxidative activities, and by gene expression of myosin heavy chain isoforms, which presented an increase in type IIa and a decrease in type I and IIb in all damaged muscles with or without cell transfer. Under our experimental conditions, these results show that muscle damage rather than satellite cell transplantation changes muscle metabolism, myosin heavy chain isoform gene expression, and, to a lesser extent, muscle contractile properties. In contrast, muscle weight and fiber size are increased both by muscle damage and by satellite cell transfer.
Insights
Muscle damage, not satellite cell transplantation, alters muscle metabolism and gene expression. However, both damage and satellite cell transfer increase muscle weight and fiber size in rabbits.
Area of Science:
- Muscle Biology
- Regenerative Medicine
- Skeletal Muscle Physiology
Background:
- Skeletal muscle regeneration is a complex process involving satellite cells.
- Understanding the role of satellite cells in muscle repair after injury is crucial for developing therapeutic strategies.
Purpose of the Study:
- To investigate the effects of satellite cell transplantation on damaged rabbit muscles.
- To analyze changes in muscle morphology, metabolism, gene expression, and function following cardiotoxin-induced injury and satellite cell autotransplantation.
Main Methods:
- Induction of muscle damage in rabbit tibialis anterior (TA) muscles using cardiotoxin injections.
- Autotransplantation of primary satellite cells into damaged muscles.
- Assessment of muscle mass, fiber size, maximal force, fatigue resistance, metabolism, and myosin heavy chain gene expression two months post-operation.
Main Results:
- Both muscle damage and satellite cell transplantation significantly increased muscle mass and fiber size.
- Muscle damage, independent of satellite cell transfer, shifted metabolism towards oxidative activities and altered myosin heavy chain gene expression.
- Maximal force recovery was observed in less severely damaged muscles (1.5 ml cardiotoxin) following satellite cell transplantation, while fatigue index increased in more severely damaged muscles (2.6 ml cardiotoxin).
Conclusions:
- Muscle damage is the primary driver of changes in muscle metabolism and myosin heavy chain gene expression.
- Satellite cell transplantation contributes to increased muscle weight and fiber size, and can aid in functional recovery of maximal force in certain injury scenarios.
- The study highlights the distinct roles of muscle damage and satellite cell transplantation in skeletal muscle repair and adaptation.
