Glucose with proteins

A number of epidemiological studies later established a link between hyperglycemia and complications such as retinopathy, neuropathy, and nephropathy (Pi-rart, 1978 DCCT, 1993). For the purpose of this review, glucose and its reactions with proteins will be considered as the primary cause underlying the complications of diabetes. Readers should note that alternatives to the involvement of glucose, and also to the reactions of glucose with proteins, exist and can be found elsewhere (Crabbe, 1987 Dvomik and Porte, 1987). 

The nonenzymatic condensation of glucose with protein amino groups results in a Schiflf base which may rearrange to form the Amadori product (Fig. 1). Both of these early products of glycation form reversibly (Roth, 1983 Baynes and Monnier, 1988). 

FIGURE 10.5 A model for the arrangement of the glucose transport protein in the erythrocyte membrane. Hydropathy analysis is consistent with 12 transmembrane helical segments. 

The incorporation and metabolism of 2-deoxy-2-fluoro-D-[ H]glucose and -D-[ H]mannose in yeast and chick-embryo cells has been studied. 2-Deoxy-2-fluoro-D-glucose, 2-deoxy-2-fluoro-D-mannose, and their GDP and UDP derivatives were found to interfere with protein (involving that of... 

The reaction between glucose and protein in the blood produces advanced glycosylation end-products (AGEs), which are metabolized in the proximal tubules. Hyperglycemia increases the synthesis of AGEs in patients with diabetes and the corresponding increase in metabolism is suspected to be a cause of nephropathy associated with diabetes.12... 

To burn the acetyl-CoA made from fat, glucose, or protein in order to make ATP in cooperation with oxidative phosphorylation. 

Figure 2.10. The dependence of the position of the fluorescence spectrum maximum on excitation wavelength for 2,6-TNS in model media (a) and in complexes with proteins (b). (a) 2,6-TNS (3 x 10-s) M in glucose glass at 20°C (1), glycerol at +1°C (2), and 80% aqueous ethanol at 20°C (3). Excitation spectra are for glycerol (4) and 80% ethanol (5). (b) 2,6-TNS in complexes with / -lactoglobulin (1), tetrameric melittin (2), human serum albumin (3), and lysozyme (4) at 20°C. Excitation spectrum (5) is for human serum albumin.

Sugars can react with proteins to form, among others, hemoglobin Aic, a measure of blood glucose control over time. 

There are numerous substances that are administered intravenously and have a direct effect on biochemical analysis. Obviously, glucose or electrolyte concentrations will be spuriously elevated if the specimen is taken from the same vein into which these substances are being administered. The presence of sulfobromophthalein dye (BSP) in serum or plasma will interfere with protein determined by the biuret method. The... 

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