Background: During aging, muscle tissue undergoes profound changes which lead to a
decline in its functional and regenerative capacity. We utilized global gene expression analysis and
gene set enrichment analysis to characterize gene expression changes in aging muscle satellite cells.
Method: Gene expression data; obtained from Affymetrix Mouse Genome 430 2.0 Array, for 14
mouse muscle satellite cell samples (5 young, 4 middle-aged, and 5 aged), were retrieved from public
Gene Expression Omnibus repository. List of differentially expressed genes was generated
based on 0.05 multiple-testing-adjusted p-value and 2-fold FC cut-off values. Functional profiling
of genes was carried out using PANTHER Classification System.
Results: We have found several differentially expressed genes in satellite cells derived from aged
mice compared to young ones. The gene expression changes increased progressively with time, and
the majority of the differentially expressed genes were upregulated during aging. While the downregulated
genes could not be correlated with specific biological processes the upregulated ones
could be associated with muscle differentiation-, inflammation- or fibrosis-related processes. The
latter two processes encompass the senescence-associated secretory phenotype for satellite cells
which alters the tissue microenvironment and contributes to inflammation and fibrosis observed in
Conclusion: Our analysis reveals that by altering gene expression pattern and expressing inflammatory
mediators and extracellular matrix components, these cells can directly contribute to muscle
wasting in aged mice.