Haemoglobin glycosylation

PI 1. Pieri, C., Testa, R., Marra, M., Bonfigli, A. R., Manfrini, S., and Testa, I., Age-dependent changes of serum oxygen radical scavenger capacity and haemoglobin glycosylation in non-insulin-dependent diabetic patients. Gerontology 47, 88-92 (2001). 

Amadori-type early glycosylation products (Brownlee et /., 1988). Protein that has been glycated in vitro is con-formationally altered. For example, the amount of early glycosylation products in vivo in diabetics, whether on haemoglobin (Hb) or basement membrane, increases when blood glucose levels are normalized by treatment. 

In a recent placebo-controlled study, 2 month s vitamin E treatment in patients with type 1 diabetes resulted in a significant dose-dependent fall in glycosylated proteins independent of changes in plasma glucose (Ceriello et al., 1991). Dose-related falls in both labile and stable fractions of haemoglobin Al also occurred. 

Red blood cells are composed of haemoglobin. Glucose sticks to the haemoglobin to make a glycosylated haemoglobin molecule (HbAlc). The more glucose present in the blood, the more HbAlc will be present. 

Ceriello A, Giugliano D, Dello Russo P, Sgambato S, D Onofrio F. Increased glycosylated haemoglobin Ai in opiate addicts evidence for a hyperglycaemic effect of morphine. Diabetologia 1982 22(5) 379. 

Orlistat has been found to be effective in the management of obese patients with co-morbid type II diabetes mellitus. Not only did the diabetics lose more weight on orlistat, the plasma levels of glycosylated haemoglobin (a measure of diabetic control) fell by 0.2% after 1 year on orlistat compared to a rise of 0.3% on placebo (Miles et al. 2002). Both orlistat and sibutramine appear to be equally effective in this group of patients, although sibutramine is better tolerated (Derosa et al. 2004). 

C3. Cannon, D. J., and Conaway, H. H., Glycosylated haemoglobin levels in a colony of spontaneously diabetic rabbits. Diabetologia 20, 242-243 (1981). 

D4. Davis, R. E., and Nicol, D. J., A rapid simplified method for routine measurement of glycosylated haemoglobin. Lancet 2, 350-351 (1978). 

D19. Dolhofer, R., Renner, R., and Wieland, O. H., Different behaviour of haemoglobin A)a c and glycosyl-albumin levels during recovery from dialretic ketoacidosis and non-acidotic coma, Diabetologia 21, 211-215 (1981). 

Gll. Cillery, P., Marquart, F.-X., Corey, J.-M., Randoux, A., and Borel, J. P., A glucose transfer from membrane glycoconjugate to haemoglobin in isolated young red blood cells another biosynthetic way for glycosylated haemoglobins. Eur. ]. Clin. Invest. 14, 317-322 (1984). 

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