Gene expression analysis of subcutaneous and omental adipose tissue from obese, insulin-resistant women. Homo sapiens

The association between central obesity and insulin resistance reflects the properties of visceral adipose tissue. Our aim was to gain further insight into this association by analysing the lipid composition of subcutaneous and omental adipose tissue in obese women with and without insulin resistance. Subcutaneous and omental adipose tissue and serum were obtained from 29 obese nondiabetic women, 13 of whom were hyperinsulinemic. Histology, and lipid and gene profiling were performed. In omental adipose tissue of obese, insulin-resistant women, adipocyte hypertrophy and macrophage infiltration were accompanied by an increase in GM3 ganglioside and its synthesis enzyme ST3GAL5; in addition, phosphatidylethanolamine (PE) lipids were increased and their degradation enzyme, PEMT, decreased. ST3GAL5 was expressed predominantly in adipose stromovascular cells and PEMT in adipocytes. Insulin resistance was also associated with an increase in PE lipids in serum. Overall design: Total RNA was isolated and up to 400 ng of total RNA per sample was labelled and hybridized to Illumina HumanHT-12_V4 expression BeadChip platform. Paired subcutaneous and omental samples from 6 women were analysed.