Endocrine Abstracts

We conducted this study to determine the degree of obesity influence on the hypoglycemic response of growth hormone and cortisol after weight loss of 5%. A total of 45 non-diabetic, male subjects followed in the outpatient endocrinological department were divided into three groups comprising 15 subjects in each group, based upon body mass index (BMI) to healthy, overweight and obese group. Metformin was administered in the dose of 500 mg daily to the overweight and obese participants. Cortisol was measured at 0, 60 and 120 min. Growth hormone (GH) was measured at −15, 0, 30, 60, 90 and 120 min. Values of cortisol and GH were compared upon changes in hypothalamo–pituitary–adrenal (HPA) response to insulin induced hypoglycemia initially and after weight loss of 5% for overweight and obese participants.

The BMI of healthy group ranged 20.0–24.5 kg/m² (Z=3.83; P≤0.001); overweight group ranged 25.9–29.7 kg/m²; and obese group ranged 30.9–34.6 kg/m².

There were no significant differences of cortisol values among groups at 0 (χ²=2.0; P=0.365); 60 (χ²=0.754; P=0.686) and at 120 min (χ²=0.466; P=0.792).

The comparison among groups were significant for differences of GH values at −15 (χ²=25; P≤0.001); 0 (χ²=16.2; P≤0.001); 30 (χ²=16.2; P≤0.001); 60 (χ²=32.8; P≤0.001); 90 (χ²=30.2; P≤0.001); and at 120 min (χ²=27.3; P≤0.001). Healthy and obese subjects significantly differed in growth hormone response at −15 (Z=4.67; P≤0.001); 0 (Z=3.83; P≤0.001); 60 (Z=2.78; P≤0.005); 90 (Z=4.67; P≤0.001) and at 120 min (Z=4.23; P≤0.001.

Changes on the various levels of HPA axis, when it is activated by a stress as it is in the case in insulin-induced hypoglycemia correspond to the degree of obesity. Weight loss of 5% was not enough for restoration of a normal stimulated growth hormone release and did not influence on the level of cortisol.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector