Serum Ghrelin Levels in Obese Patients: The Relationship to Serum Leptin Levels and Soluble Leptin Receptors Levels

M. ROSICKÁ, M. KRŠEK, M. MATOULEK, Z. JARKOVSKÁ, J. MAREK, V. JUSTOVÁ, Z. LACINOVÁ

Received March 18, 2002
Accepted May 27, 2002

Summary
Ghrelin is a new endogenous ligand for the growth hormone secretagogue receptor. It activates the release of growth hormone from the pituitary and it also participates in the regulation of energy homeostasis. The aim of the study was to characterize changes in serum ghrelin levels in obese subjects and their relationship to the serum levels of leptin and soluble leptin receptor. Eight obese patients (6 women and 2 men) with body mass index (BMI) 40.313.4 kg.m-2 and eight healthy controls (5 women and 3 men) with BMI 22.71.3 kg.m-2 were examined. The ghrelin serum levels (165.058.1 vs. 343.3781.96; p0.001) and soluble leptin receptor serum levels (7.253.44 vs. 21.804.99; p0.0001) were significantly lower in obese patients. The leptin serum levels (23.4512.90 vs. 6.412.96; p0.005) were significantly higher compared to the lean subject group. In both measured groups the levels of serum leptin significantly positively correlated with BMI. We proved a significantly lower serum ghrelin levels in the group of obese patients in comparison with the control group.

Key words
Ghrelin • Leptin • Soluble leptin receptor • Neuropeptide Y • Obesity

Reprint requests
Martina Rosická, M.D., Third Dept. of Internal Medicine, First Faculty of Medicine and General University Hospital, Charles University, U nemocnice 2, 128 08, Prague 2, Czech Republic, e-mail: rosi@email.cz.