Expression of obesity- and type-2 diabetes-associated genes in omental adipose tissue of individuals with obesity

•Gene expression in VAT of obese (OB) patients depends on T2D diagnostics.•Expression of HP in VAT correlates positively with cholesterol levels in blood.•Adipocyte differentiation/browning related genes downregulate in OB with T2D patients. Obesity and type 2 diabetes mellitus are two pathologies that share metabolic abnormalities in most of the cases; however, there are differences as well. Some studies have reported that approximately 30% of obese patients have normal glucose and lipid levels in blood despite an accumulation of abdominal adipose tissue. Here, we compare the gene expression in adipose tissue of several genes associated with obesity and/or diabetes between obese patients without T2D and obese patients with T2D. Omental adipose tissue was collected during the patients elective bariatric surgery. Gene expression was determined by real-time PCR. Phenotypic variables were correlated with gene expression and 2^-ΔΔCt relative expression analysis between groups was performed. The stronger correlations in the obese without T2D or reference group was between ICAM1 and HbA1c; HP and TC and LDL while in the obese with diabetes or case group the correlation occurred between CSF1 and BMI. A correlation between HP and TC was found in the case group as well. The expression of VEGFA, CCND2, IL1R1 and PTEN was downregulated in the obese with T2D group. This study identified genes whose expression is different between obese subjects with and without diabetes. Those genes are related to inflammation, cholesterol transport, adipocyte differentiation/expansion and browning.