It acts on the control of food intake through specific receptors, located in the hypothalamus and in peripheral organs such as the liver. This hormone acts on the central nervous system, promoting reduced food intake and energy expenditure. In a study on the blood of obese and lean individuals, Pardina et al. observed higher LEP levels in morbidly obese individuals compared to lean individuals. The authors also reported that LEP levels were reduced one year after bariatric surgery, becoming identical to those of the control group. Esteghamati et al. also observed that obese individuals with metabolic syndrome have higher leptin levels, suggesting that hyperleptinemia is associated with this syndrome. In the present study, as expected, we observed a higher LEP expression in the subcutaneous fat of the obese group compared to control, whereas no difference was observed in the liver or omentum. The profiles of gene expression of subcutaneous abdominal fat and of the omentum are different, including the expression of some proteins, LEP among them. Studies conducted on samples of abdominal subcutaneous fat and omentum have shown that the gene expression of LEP is higher in the abdominal subcutaneous fat, a result observed both in men and in women and in obese and normal weight individuals. Since we did not detect a significant difference in LEP expression in the omentum of the obese group compared to control, we may assume that this was due to the fact that the highest production of LEP occurs in subcutaneous. In addition, Carmina et al. observed that LEP expression decreases with increasing BMI both in the omentum and in the visceral subcutaneous fat. We may also suggest that another reason for the lack of a difference Ganoderic-acid-G between groups in the expression of this gene in the omentum is that obese individuals have a lower mRNA production for this protein in the omentum and that this production is further reduced with increasing BMI. Elevated circulating leptin concentration has been associated with obese patients with insulin resistance compared to normal weight individuals. In contrast, the circulating levels of leptin receptors are lower in obese individuals than in normal weight individuals. Also, the proportion of free circulating levels of LEP and LEPR is significantly higher in obese than in non-obese individuals. Se��ron et al. showed that expression of mRNA was elevated in subcutaneous fat of lean women and diminishes around 70% in the obese group. In visceral fat of both groups, the expression of this receptor is low. In the present study we did not detect a significant difference in the gene expression of LEPR in the obese group compared to control in any of the tissues Procyanidin-B1 analyzed. A possible explanation for this observation is the probably small number of individuals studied. Obesity is also known to be associated with abnormal IGF1 secretion. A 1997 study by Nam et al. detected no significant difference in total IGF1 between lean and obese individuals, but showed a higher free IGF1 concentration in the obese group. Gomez et al. observed a lower IGF1 concentration in obese individuals, as also reported later by Pardina et al.. The present results showed that IGF1 is more expressed in the subcutaneous fat of obese subjects compared to control, whereas its expression is higher.