A survey of genes differentially expressed in subcutaneous and visceral adipose tissue in men

Adipose tissue located within the abdominal cavity has been suggested to be functionally and metabolically distinct from that of the subcutaneous compartment. These differences could play a role in obesity-related complications. The aim of this study was to compare gene expression profiles of subcutaneous and visceral adipose tissues of 10 nondiabetic, normolipidemic obese men. Affymetrix human U133A arrays (10 arrays for subcutaneous fat samples and 10 arrays for visceral fat samples) were used. Differential gene expression was confirmed by real-time polymerase chain reaction in a subset of genes. A total of 5894 transcripts were detected in both depots in all 10 subjects, and 409 transcripts representing 347 encoded genes were differentially expressed. Of these, 131 genes were expressed at higher levels in subcutaneous adipose tissue, and 216 were expressed more abundantly in visceral fat. Differentially expressed profiles included genes of the Wnt signaling pathway, as well as CEPBA and HOX genes. In addition, genes involved in lipolytic stimuli and cytokine secretion were differentially expressed. The identification of a consistent and rather uniform pattern of differentially expressed genes between the two fat depots using multiple array replicates (10 arrays per fat compartment) generated new perspectives for future research on regional differences in adipose tissue biology.