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

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 eth nic groups. This cross-sectional study was conducted to determine adiponectin level and its association with insu lin sensitivity in 20 adult overweight type-2 diabetic and 20 healthy over-weight non-diabetic Iranian men for the first time. Body fat mass (Bio-electric impedance), serum level of adiponectin (ELISA), fasting blood sugar and fasting in sulin were measured. Insulin sensitivity was calculated using QUICKI. 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 cor related 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 rela tion was only statistically sig nificant in non-diabetics (r= +0.5; P= 0.04). The relation between insulin sensitivity and mean of adiponectin level was mar ginally significant even after adjustment for group (diabetic and non-dia betic), age and fat mass. Our findings are consistent with the studies on different ethnic groups which have indicated lower adi ponectin lev els in diabetics. Also our results confirm the relationship between a low adiponectin level and insulin sen sitivity reported in earlier studies.