Subcutaneous adipose tissue transcriptome highlights specific expression profiles in pediatric severe obesity: a pilot study

Pediatric obesity prevalence is rapidly rising worldwide and “omic” approaches are helpful in obesity molecular pathophysiology investigation. This work aimed at the identification of transcriptional differences in subcutaneous adipose tissue (scAT) of children with overweight (OW), obesity (OB) or severe obesity (SV) respect those with normal weight (NW). Periumbilical scAT biopsies were collected from 20 male children aged 1-12 years. Considering BMI z-score, chil-dren were stratified into 4 groups: SV, OB, OW, NW. scAT RNA-Seq analyses were performed, differential expression analysis was achieved using the DESeq2 R package. Pathways analysis was performed to gain biological insights on gene expression. Our data highlight the significant deregulation in both coding and non-coding transcripts in the SV group when compared to NW, OW, and OB. KEGG pathway analysis showed involvement for coding transcripts mainly in li-pid metabolism. GSEA analysis revealed upregulation of lipid degradation and metabolism in SV vs OB and SV vs OW. Bioenergetic processes and the catabolism of branched-chain amino acids resulted upregulated in SV when compared to OB, OW, NW. In conclusion, we report for the first time that a significant transcriptional deregulation occurs in periumbilical scAT of children with severe obesity with respect to normal weight, overweight or mild obesity. Comparative gene expression profiling analysis of RNA-seq data for subcutaneous adipose tissue (scAT) of children with overweight (OW), obesity (OB) or severe obesity (SV) respect those with normal weight (NW)