Ricerc@Sapienza

Adult adipose tissue-derived mesenchymal stem cells (ASCs) constitute a vital
population of multipotent cells capable of differentiating into numerous end-organ
phenotypes. However, scientific and translational endeavors to harness the regenerative
potential of ASCs are currently limited by an incomplete understanding of the
mechanisms that determine cell-lineage commitment and stemness. In the current
study, we used reduced representation bisulfite sequencing (RRBS) analysis to identify
epigenetic gene targets and cellular processes that are responsive to 50-azacitidine (50-
AZA). We describe specific changes to DNA methylation of ASCs, uncovering pathways
likely associated with the enhancement of their proliferative capacity. We identified 4,797
differentially methylated regions (FDR < 0.05) associated with 3,625 genes, of which
1,584 DMRs annotated to the promoter region. Gene set enrichment of differentially
methylated promoters identified “phagocytosis,” “type 2 diabetes,” and “metabolic
pathways” as disproportionately hypomethylated, whereas “adipocyte differentiation”
was the most-enriched pathway among hyper-methylated gene promoters. Weighted
coexpression network analysis of DMRs identified clusters associated with cellular
proliferation and other developmental programs. Furthermore, the ELK4 binding site
was disproportionately hyper-methylated within the promoters of genes associated with
AKT signaling. Overall, this study offers numerous preliminary insights into the epigenetic
landscape that influences the regenerative capacity of human ASCs.