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Updated: May 12, 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
Satellite cell pool expansion is affected by skeletal muscle characteristics
Filippo Macaluso1, Naomi E Brooks, Carola U Niesler
1Department of Physiological Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa.
Introduction:
We investigated changes in satellite cell (SC) pool size after an acute bout of strenuous exercise and evaluated the influence of baseline SC count and fiber type.
Methods:
Participants completed a downhill running (DHR) intervention (5 × 8 min, 2-min rest; 80% VO2max ; -10% gradient). Muscle biopsies were taken 7 days before VO₂max and 7-9 days after the DHR intervention. Delayed-onset muscle soreness (DOMS) and creatine kinase activity (CK) were measured on days 1, 2, 7, and 9 post-DHR. SCs were identified by Pax7 and laminin staining. Relative distribution of MHC isoforms was determined by electrophoresis.
Results:
DOMS and CK peaked on day 1 post-DHR (P < 0.01). The SC pool increased (26%) after DHR (P = 0.005). SCs/total myonuclei after recovery correlated with baseline SCs (r = 0.979, P = 0.003) and VO₂max (r = 0.956, P = 0.011), whereas change in SC pool (Pax7(+) cells/total myonuclei: recovery minus baseline) tended to correlate with percent MHC II (r = 0.848; P = 0.06).
Conclusion:
Interindividual physiological characteristics affect SC pool expansion after a single bout of DHR and are influenced by VO₂max .
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