INVESTIGATION OF THE RELATIONSHIPS OF OBESITY WITH MELATONIN AND DEHYDROEPIANDROSTERONE LEVELS

Abstract

Objective: Melatonin is synthesized in pineal gland and plays a role in energy metabolism and the weight-reducing effects. Dehydroepiandrosterone (DHEA) is synthesized primarily by the zona reticularis of adrenal cortex and to a lesser degree by the gonads. DHEA has antioxidant, antilipidperoxidative, antiinflammatory, antiatherogenic, antiaging and weight-reducing or preventing effects. Our aim of this study was to investiagate blood DHEA, melatonin, insulin resistance (IR) and lipids levels and correlations between them in obese and nonobese subjects. Material and Method: The study was performed on 33 obese subjects ((16 male (M), 17 female (F)) aged 40.03 +/- 8.47 years and 33 normal weight healty controls (15M, 18F) aged 28.76 +/- 6.22 years. In both groups, DHEA, melatonin, IR, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol and triglyceride levels and correlations between them were investigated. DHEA and melatonin levels were determined by ELISA method and insulin, fasting blood glucose levels and lipid parameters were determined by rutin method using commercially avilable kits. IR was calculated using a formula. Results: There was no statistically significant differences between DHEA and melatonin levels of the groups and there were no correlations between them in both groups. However, there was a significant negative correlation between DHEA and triglyceride levels in the obese group (r=-0.342, p<0.05). Conclusion: Our results show that DHEA and melatonin levels were not changed in obesity and they have no effects on IR. However significant negative correlation between DHEA and triglyceride levels in obese subjects needs to be more investigated in terms of the effect of DHEA on adipose tissue and obesity.