The plasminogen activator inhibitor 1(PAI-1), an important inhibitor of the fibrinolytic system, which is also an adipokine, showed an increased level in relation to the obesity degree from 8591.6 pg/mL in Ctrl group to 12323.1 pg/mL in ObII/III. This evidence concerns the gene SERPINE1 and obesity due to melanocortin 4 receptor deficiency.