Background Advanced glycosylation end product (AGE) formation is a major mechanism for the development of complications in diabetes, and the possible roles of insulin-like growth factor 1 (IGF-1) and IGF binding protein 3 (IGFBP-3) are not clearly established.
Methods
We examined the associations of AGEs, free IGF-I and IGFBP-3 in Type 2 diabetes mellitus (DM) patients under diverse conditions. In a crosssectional design we studied 110 subjects (67 women and 43 men): nondiabetic controls in group 1, (n=15) and diabetes patients as follows: group 2, without complications (n=25); group 3, with chronic complications (n=25); group 4, with acute or chronic infections (n=24); group 5, hospitalized for reasons unrelated to diabetes (n=9); group 6, with end-stage renal disease (ESRD) (n=12). AGEs were determined by a spectro¯uorometric method (HPLC). Insulin and IGFBP-3 were measured by RIA and free IGF-1 with an IRMA method.
Results AGEs were 13-fold higher in patients with ESRD ( p<0.001), and lower in healthy individuals. Free IGF-1 was lower in the patients with complications ( p=0.017), with infections ( p=0.006) and hospitalized ( p=0.04). IGFBP-3 was higher in hospitalized patients ( p=0.017). AGEs were associated with free IGF-1 (r=0.41, p=0.04) in the group with complications, and with HbA 1c (r=x0.90, p=0.002) in hospitalized patients. In the total group, free IGF-1 (r=x0.25, p=0.008), and IGFBP-3 (r=x0.22, p=0.021) were associated with HbA 1c .
Conclusion
We concluded that AGEs were markedly increased in diabetic patients with ESRD, IGF-1 was decreased in patients with infections and hospitalized, and was negatively associated with HbA 1c . IGFBP-3 was increased in hospitalized patients, with higher levels in patients with long bone fractures. A complex interaction of humoral factors may participate in the acceleration of complications of diabetes.