Increased activity of serum fucosyl transferase in diabetic patients.

Serum fucosyl- (but not sialyl-) transferase activity was significantly (p less than 0.001), increased in 57 patients with diabetes mellitus. A correlation also existed in diabetics between fucosyl- (but not sialyl-) transferase activity and glycosylated serum protein (r = 0.52, p less than 0.001). Sialyl (but not fucosyl) transferase activity on the other hand correlated with hemoglobin A1 (r = 0.28, p less than 0.05). The data suggest a relationship between fucosyl/sialyl- transferase activities and long-term glucose control. Changes in these enzyme activities may affect cell membrane glycoprotein turnover which may be of importance both for insulin receptor function and later development of diabetic microangiopathy.