Plasma insulin, cholecystokinin, galanin, neuropeptide Y and leptin levelsin obese women with and without type 2 diabetes mellitus

Obesity is an important factor predisposing to type 2 diabetes mellitus, es pecially for postmenopausal women. Experimental studies provided evidences that leptin, cholecystokinin (CCK), galanin (GAL], neuropeptide Y (NPY) and insulin are involved in feeding behaviour. The aim of the study was to eva luate their possible relationships in obese and diabetic women. Three groups of postmenopausal women (FSH > 30 mIU/ml) were evaluated: 8 di abetic (mean age 56.6 +/- 6.9 y, BMI 29.8 +/- 5.3 kg/m(2)), 10 obese nan-di abetic (mean age 49.6 +/- 5.4 y, BMI 36.0 +/- 3.7 kg/m(2)) and 12 non-diabe tic controls (mean age 52.7 +/- 3.5 y, BMI 27.3 +/- 1.9 kg/m(2)). For each patient BMI and WHR were measured and calculated. Blood samples were collec ted at 8:00 a.m. after an overnight fast. Plasma concentrations of FSH, lep tin, CCK, GAL, NPY and insulin were determined using commercial RIA kits. Mean plasma NPY concentration was significantly higher in diabetic women th an in controls (190.1 pg/ml +/- 85.4 vs 120.4 +/- 36.6). Compared to contro ls, mean plasma leptin level was significantly higher in obese non-diabetic women (32.9 ng/ml +/- 9.2 vs 18.9 +/- 9.1). No significant differences wer e found between obese non-diabetic and diabetic women. In diabetic subjects positive correlations were found between: CCK and lept in (r = 0.8295; P = 0.011), CCK and insulin (r = 0.7832; P = 0.022), leptin and insulin (r = 0.9302; P = 0.001). In obese subjects a positive correlation between WHR and GAL (r = 0.6624; P = 0.037) and a negative between GAL and insulin (r = -0.6795; P = 0.031) w ere found. In controls positive correlations were found between WHR and CCK (r = 0.6412; P = 0.025), GAL and insulin (r = 0.630; P = 0.028) and negati ve between CCK and NPY (r = -0.6505; P= 0.022). Our results, ie higher mean plasma NPY levels in postmenopausal diabetic wo men and positive correlation of CCK with leptin and insulin, may suggest th e role of these neuropeptides in metabolic disorders leading to type 2 diab etes mellitus.