Serum Level of Adiponectin and Its Association with Insulin Sensitivity in Overweight Diabetic and Non-Diabetic Iranian Men

Abstract

Background: Adiponectin is a protein produced exclusively by adipose tissue; the reduced level of which has been shown to be involved in a variety of obesity-related disorders, such as insulin resistance and diabetes, in different eth­nic groups. This cross-sectional study was conducted to determine adiponectin level and its association with insu­lin sensitivity in 20 adult overweight type-2 diabetic and 20 healthy over-weight non-diabetic Iranian men for the first time.

Methods: Body fat mass (Bio-electric impedance), serum level of adiponectin (ELISA), fasting blood sugar and fasting in­sulin were measured. Insulin sensitivity was calculated using QUICKI.

Results: As expected, the mean adiponectin concentration was lower in diabetics (7.7 ±3µg/ml) than non-diabetics (8.1 ± 2µg/ml); however, the difference did not achieve statistical significance (P= 0.5). Adiponectin negatively cor­related with fat mass. This correlation was stronger in diabetics with a higher fat mass (r= -0.3 in diabetics vs. r= -0.01 in non-diabetics; p: N.S.). Adiponectin positively related with insulin sensitivity in both groups, although this rela­tion was only statistically sig­nificant in non-diabetics (r= +0.5; P= 0.04). The relation between insulin sensitivity and mean of adiponectin level was mar­ginally significant even after adjustment for group (diabetic and non-dia­betic), age and fat mass.

Conclusion: Our findings are consistent with the studies on different ethnic groups which have indicated lower adi­ponectin lev­els in diabetics. Also our results confirm the relationship between a low adiponectin level and insulin sen­sitivity reported in earlier studies.