Expression of visfatin mRNA in peripheral blood mononuclear cells is not correlated with visfatin mRNA in omental adipose tissue in women with polycystic ovary syndrome

BACKGROUND Visfatin, which is secreted predominantly from visceral adipose tissue, has an insulin-mimetic action and may play a role in the regulation of insulin sensitivity in humans. Peripheral blood mononuclear cells (PBMCs) from venous blood samples are the most accessible tissue for the analysis of gene expression. The aims of the study were to compare the expression of visfatin in PBMCs with that in omental adipose tissue in women with polycystic ovary syndrome (PCOS). METHODS Visfatin mRNA was measured in omental adipose tissue and PBMCs from 10 women with PCOS and 10 healthy controls, matched for BMI and age, using the real-time polymerase chain reaction (PCR). RESULTS The expression of visfatin mRNA in both omental adipose tissue and PBMCs from the women with PCOS was significantly higher (P= 0.01 and P= 0.05, respectively) than that in the controls. This finding indicated that mononuclear cells are a potential source of visfatin in women with PCOS. However, only the expression of visfatin mRNA in adipose tissue, not that in PBMCs, showed a significant positive correlation with insulin levels 2h after glucose loading (P= 0.044, r2 = 0.45), and with homeostasis model assessment–insulin resistance (HOMAIR; P= 0.035, r2 = 0.47). In addition, the expression of visfatin mRNA in PBMCs did not correlate with the expression of visfatin mRNA in omental adipose tissue. CONCLUSIONS PCOS is associated with increased visfatin mRNA concentrations in PBMCs and in omental adipose tissue. However, only visfatin mRNA concentration in omental adipose tissue is closely correlated with BMI and insulin resistance.