GLYCOSYLATED ALBUMIN (GLY-ALB) AND GLYCOSYLATED TRANSFERRIN (GLY-TRANS) AS SHORT-TERM MARKERS OF CONTROL IN DIABETES

Abstract

Glycosylated hemoglobin (gly-hgb) is widely used as a marker of long term diabetic control (2-3 months), while glycosylated albumin (half-life 14 days) is a marker of short term control (2-4 weeks). We separated glycosylated and non-glycosylated proteins by an affinity column method (Glyc-Affin™, Isolab) and determined levels of albumin (colorimetrically) and transferrin (radial immunodiffusion). Serum was collected from children with type I diabetes before and 10 days after attending a camp session in which blood glucose levels were carefully controlled. Gly-hgb in these subjects ranged from 4.6 to 14.6% (mean ± SEM= 8.1 ± 0.2%). Mean pre-camp gly-alb in 73 subjects was 16.4 ± 0.6% (SEM), which was elevated compared to the mean of levels in 20 non-diabetic control subjects (8.7 ± 0.3% SEM), and correlated well with levels of gly-hgb (r=0.71). After 10 days mean gly-alb fell to 14.6 ± 0.5% (SEM) (p<0.00001), near the predicted post-camp value of 13.4% if control had been ideal for the 10 days. Initial levels of gly-trans in 44 of these subjects ranged from 4.5% to 22.3% (mean ± SEM=11.4 ± 0.6%), and was higher than the mean of 3.8 ± 0.3% (SEM) in 20 non-diabetic controls. Mean post-camp gly-trans fell to 8.2 ± 0.3% (SEM) (p< 0.00001), near the predicted post-camp mean of 7.0 ± 0.4%. Both gly-alb and glytrans appear to be reliable markers of short term glycemic control; gly-trans (half-life 8 days) was more sensitive over this 10-day period than gly-alb.