Clinical Utility of Nonenzymatically Glycosylated Blood Proteins as an Index of Glucose Control

Abstract

This study compares the utility of nonenzymatically glycosylated serum proteins (lys-GSP) to glycosylated hemoglobins (HbA1a-c) as control indices of glucose homeostasis in patients with IDDM. The diagnostic value of lys-GSP was also examined in patients with non-insulin-dependent diabetes mellitus, in subjects with impaired glucose tolerance, and in two patients with insulinoma. The intraindividual fluctuation of lys-GSP in normoglycemic subjects is very small, resulting in an interindividual range of 3.0 +/- 0.3 lysine-bound glucose/mg protein (means +/- SD, N = 52). HbA1a-c with a normal range of 6.4 +/- 0.9% (N = 52) shows greater variability. In IDDM there is no overlap of lys-GSP levels between the normal and the diabetic range at the 95% confidence level. In patients treated with an open-loop insulin delivery system failure of normalization of the glucose balance was clearly discernible by an elevation of GSP. In contrast, in about 40% of the patients with incomplete glycemic control the HbA1a-c levels fell within the normal range. The utility of lys-GSP for diagnosis of diabetes is compared with the results of 60 oral glucose tolerance tests. Two patients suffering from insulinoma displayed decreased lys-GSP values. From these results it appears that determination of lys-GSP represents a more sensitive parameter for long-term control than HbA1a-c and is suitable for monitoring even small fluctuations of blood glucose.

Effect of aerobic exercise training on oxidative stress in patients with type 2 diabetes mellitus

“…Serum glycated albumin levels have been shown to reflect overall glycemic control during the previous 2 weeks [33,34], whereas HbA 1C provides an integrated measurement of blood glucose during the previous 2 to 3 months [35,36]. Schleicher et al [37] proposed that glycated serum protein is a more sensitive index than HbA 1C , possibly as a consequence of the higher albumin content of serum. Furthermore, Monnier et al [38] reported that urinary isoprostane level, which is one of the oxidative stress markers [39], was positively correlated with short-term glucose fluctuations, but not HbA 1C , in patients with type 2 diabetes mellitus.…”

Kinetics of HbA1c, Glycated Albumin, and Fructosamine and Analysis of Their Weight Functions Against Preceding Plasma Glucose Level

“…Since glycation takes place throughout the life span of hemoglobin and serum proteins, the levels of glycated proteins reflect the degree of hyperglycemia during their life span. From clinical observations, the HbA lc level has been thought to reflect the mean plasma glucose level during the preceding 1-3 months (5-9), whereas GA and FA levels have been thought to reflect the mean plasma glucose level during the preceding 1-2 weeks (10)(11)(12)(13)(14)(15)(16)(17). However, there are few reports addressing the question of exactly how the preceding plasma glucose level contributes to the level of glycated proteins.…”

Beneficial effects of Chinese prescription Kangen-karyu on diabetes associated with hyperlipidemia, advanced glycation endproducts, and oxidative stress in streptozotocin-induced diabetic rats

“…Serum AGEs such as glycosylated albumin and hemoglobin have been produced by the glycation reaction, which resulted in a decrease in free protein levels (Schleicher et al, 1984). So, serum AGEs are clinically used as an index of glucose control in diabetes.…”