Relationship Between Insulin like Growth Factor-1 and Leptin in Type II Diabetic Patients

Diabetes is a common endocrine disease in humans. Leptin secretion is influenced by many factors and although the growth hormone/insulin like growth factor (GH/IGF) axis plays an important role in the regulation of body composition, the physiological interaction between Leptin and IGF-1 system remain unknown. The aim of this study was to investigate the correlation between Leptin and IGF-1 in type II diabetics and controls. Materials and Methods: This case-control study was consisted of 38, type 2 diabetics (20 males and 18 females, mean age 49.33 +/- 11.33, years) and 46 healthy controls (16 males and 30 females, mean age 49.52 +/- 7.99, years). We measured the concentrations of fasting plasma glucose (FPG), IGF-1, hemoglobin A1C (HbA1c) and insulin like growth factor binding protein-3(IGFBP-3) in both groups. FPG was measured by the enzymatic glucose oxidase method and the Hb Gold analyzer HPLC was used to measure HbA1C. For determination of leptin, IGF-1, IGFBP-3 and insulin concentrations, the enzyme linked immunosorbent assay (ELISA) method was used. P< 0.05 was considered statistically significant. Results: Means of BMI and age did not differ significantly between the two groups. Mean serum levels of IGF-1, leptin, insulin, FPG and HbA1c concentrations in type 2 diabetics were significantly higher than in controls (p< 0.05). In both groups, mean serum levels of leptin in males, were statistically lower than in females. Strong correlations were found between IGF-1 and IGFBP-3, leptin and insulin, IGF-1 and age, and between BMI and FPG in both patients and controls (p<0.05). A negative correlation was observed between IGF-1 and HbA1c in patients and controls (p<0.05). Conclusion : It is concluded that leptin and the IGF-1 system, could influence body composition and fat content, particularly in obese and overweight diabetic patients.