Relationship between insulin like growth factor-1 and leptin in type II diabetic patients

ABSTRACT

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. 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. 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]. It is concluded that leptin and the IGF-1 system, could influence body composition and fat content, particularly in obese and overweight diabetic patients