The preservation of insulin sensitivity in obese women without diabetes.
OBJECTIVE
To assess insulin sensitivity, pancreatic beta-cell function, and compare circulating levels of adiponectin and ghrelin in obese women with and without diabetes.


METHODS
Ninety-nine obese women with a body mass index (BMI) > or = 25 kg/m2 and age at least 40 years without previous history of diabetes participated in this study. Oral glucose tolerance test was performed in all subjects. Serum for insulin, adiponectin, and ghrelin were obtained at baseline. Data were expressed as mean +/- SEM.


RESULTS
Oral glucose tolerance test revealed 66 non-diabetic (ND) and 33 diabetic (D) subjects. Despite a similar degree of obesity, women without diabetes had near normal insulin sensitivity (ND, 105.7 +/- 6.4%; D, 62.3 +/- 5.9%; p < 0.001) and beta cell function (ND, 95.4 +/- 3.0%; D, 79.0 ++/- 6.1%; p < 0.001) as assessed by the HOMA model. Non-diabetic subjects had higher serum adiponectin levels despite similar BMI (ND, 8.3 +/- 0.4 mg/ml; D, 6.3 +/- 0.4 mg/ml; p < 0.01). Obese subjects with diabetes had lower serum ghrelin levels than obese non-diabetic subjects (ND, 1027.2 +/- 32.0 pg/ml; D, 875.1 +/- 34. 6 pg/ml; p < 0.05).


CONCLUSIONS
Obese women without diabetes have less pancreatic beta cell dysfunction and higher insulin sensitivity than obese women with diabetes. Higher circulating adiponectin may play protective roles in obese non-diabetic subjects, but the significance of higher ghrelin level should be further explored.
Ngarmukos
Chardpraorn
C
Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. tecng@mahidol.ac.th
Chanprasertyothin
Suwanee
S
Puavilai
Gobchai
G
Ongphiphadhanakul
Boonsong
B
D052242:Adiponectin / Q000097:blood*; D050154:Adiposity; D000328:Adult; D000886:Anthropometry; D015992:Body Mass Index; D016022:Case-Control Studies; D003920:Diabetes Mellitus / Q000503:physiopathology*; D005260:Female; D054439:Ghrelin / Q000097:blood*; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D050417:Insulin-Secreting Cells; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*; D012307:Risk Factors
D052242:Adiponectin; D054439:Ghrelin