Muscle Tissue Remodeling Following Intramuscular Fat Grafting: Structural and Transcriptomic Insights
Mário Mendanha, Raquel Soares, Carla Luís, Sílvia Santos Pedrosa, Carlos Ferreira, Inês Pinto-Ribeiro, Ana Raquel Madureira, Lara QueirósAbstract
Background
Liposculpture with autologous fat grafting represents an advanced body contouring approach that enhances muscular definition and volume through selective extraction and anatomical redistribution of adipose tissue. While these procedures are primarily used for aesthetic refinement, emerging evidence suggests autologous fat transfer may also induce significant biological adaptations within grafted muscle.
Objectives
Evaluate the biological implications of intramuscular fat grafting.
Methods
A retrospective within-subject controlled study was conducted. One year postoperatively, paired biopsies were harvested from the fat-grafted muscle pectoralis major (MPM) and the untreated muscle vastus lateralis (MVL) in 7 male patients following liposculpture and intramuscular fat transfer using the Percutaneous Retrograde Intramuscular Echo-Guided Fat Grafting (PRIME-GRAFT) technique. Subsequent assessments were performed via histological and transcriptome analyses.
Results
Histological evaluation comparing treated MPM to untreated MVL one year following liposculpture and intramuscular fat grafting via PRIME-GRAFT technique demonstrated significant reduction in fibrosis and elevated glycogen concentrations within treated muscles. Reduced collagen deposition and elevated glycogen content findings are biologically associated with improved tissue composition. Microarray transcriptomic profiling revealed 70 differentially expressed genes, 51 being up-regulated and 19 down-regulated. Differentially expressed genes showed upregulation of genes associated with Gene Ontology (GO) terms related to muscle structure, organization, extracellular matrix remodeling, energy metabolism, stem cell and cytoskeleton proliferation and organization.
Conclusions
PRIME-GRAFT technique induces histological and transcriptional signatures suggesting improved muscle stress resilience, homeostasis, and tissue regeneration. Autologous intramuscular fat transfer provides not only aesthetic improvement but also histological and transcriptomic changes consistent with enhanced muscle integrity and regenerative potential.