Plasma adiponectin level is associated with insulin-stimulated nonoxidative glucose disposal.
BACKGROUND
Impaired nonoxidative glucose disposal and decrease in mitochondrial glucose oxidation both contribute to insulin resistance in diabetic subjects.


OBJECTIVE
In the present study, we investigated whether plasma adiponectin is associated with glucose oxidation and nonoxidative glucose disposal in subjects with and without type 2 diabetes.


METHODS
Euglycemic-hyperinsulinemic clamp was performed in 42 type 2 diabetic (T2DM) and 13 nondiabetic (non-DM) subjects. The whole-body glucose disposal rate (GDR) was evaluated as the mean of the glucose infusion rate during steady state of the clamp. Glucose and fat oxidation rates were assessed by indirect calorimetry, and nonoxidative glucose disposal rate was calculated by subtracting glucose oxidation rate from GDR.


RESULTS
Plasma adiponectin level was significantly lower in T2DM than non-DM (2.87 +/- 1.40 vs. 3.96 +/- 2.39 microg/ml, P = 0.045). GDR (3.39 +/- 1.53 vs. 4.83 +/- 1.70 mg/kg x min, P = 0.006) and nonoxidative glucose disposal rate (1.89 +/- 1.39 vs. 3.11 +/- 1.76 mg/kg x min, P = 0.012) were significantly lower in T2DM, compared with non-DM, although no difference was found in glucose oxidation rate between the two groups. In all subjects, plasma adiponectin level was positively correlated with GDR (r = 0.351, P = 0.009) and nonoxidative glucose disposal rate (r = 0.324, P = 0.016) but not glucose oxidation rate. There was no significant correlation between plasma adiponectin level and fat oxidation, either before or during the clamp.


CONCLUSIONS
In conclusion, plasma adiponectin level is associated with nonoxidative glucose disposal, which is reduced in type 2 diabetic subjects. Our results suggest that adiponectin controls insulin sensitivity by modulating the glycogen synthetic process in human skeletal muscle.
Yokoyama
Hisayo
H
Department of Metabolism, Endocrinology, and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan. yock@med.osaka-cu.ac.jp
Emoto
Masanori
M
Mori
Katsuhito
K
Araki
Takahiro
T
Teramura
Megumi
M
Koyama
Hidenori
H
Shoji
Tetsuo
T
Inaba
Masaaki
M
Nishizawa
Yoshiki
Y
D052242:Adiponectin / Q000097:blood*; D000293:Adolescent; D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D002151:Calorimetry; D002153:Calorimetry, Indirect; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D049629:Waist-Hip Ratio
D052242:Adiponectin; D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin