Photometric determination of glycosylation of hemoglobin in diabetes mellitus.
We evaluated glycosylation of hemoglobin (HbA + HbA1) in 25 control subjects and in 133 diabetic patients who were in various stages of blood glucose control, by measuring ketoamine-linked hexoses in hemoglobin. These hexoses were converted by digestion with 10 mol/L acetic acid for 16 h at 100 +/- 5 degrees C to 5-hydroxymethylfurfuraldehyde, which was quantitated by reaction with 2-thiobarbituric acid. Glycosylation of hemoglobin was expressed as micromoles of hydroxymethylfurfuraldehyde per gram of globin protein (the "HMF index"). A mean HMF index of 1.67 (SD = 0.23) was obtained for controls; that for diabetic patients was 2.93 (SD 0.95). The index correlated well (r = 0.83, p < 0.001) with average blood glucose concentration as measured during the preceding 16 weeks, over a wide range of glucose values (1 to 6 g/L). It correlated even better (r = 0.92, p < 0.001) when corrected for variations in hemoglobin concentration. Thus measurement of ketoamine-linked hexoses of hemoglobin or HMF index provides an independent and useful alternative to the currently used methods that measure only HbA1 or HbA1c.
D001786:Blood Glucose / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D003920:Diabetes Mellitus / Q000097:blood*; D005260:Female; D005662:Furaldehyde / Q000031:analogs & derivatives*; D006027:Glycosides / Q000032:analysis*; D006441:Hemoglobin A / Q000031:analogs & derivatives* / Q000032:analysis; D006601:Hexoses; D006801:Humans; D008297:Male; D010783:Photometry; D013858:Thiobarbiturates
D001786:Blood Glucose; D006027:Glycosides; D006601:Hexoses; D013858:Thiobarbiturates; C008046:5-hydroxymethylfurfural; D006441:Hemoglobin A; D005662:Furaldehyde