Separation of serum glycated proteins by agarose gel electrophoresis and nitroblue tetrazolium staining in diabetic and normal cats.
BACKGROUND
The total glycated protein (fructosamine) concentration in serum consists mainly of glycated albumin and lipoproteins. Measurement of fructosamine is used to diagnose and monitor diabetes mellitus in cats.


OBJECTIVE
The aims of this study were to measure glycated proteins in diabetic and healthy (nondiabetic) cats using a semiquantitative technique and to determine whether measurement of any of the fractions of glycated protein could be potentially advantageous for the diagnosis and monitoring of diabetic cats.


METHODS
Serum samples from 6 cats with diabetes mellitus and 10 clinically healthy adult cats were assayed for total glycated protein using a nitroblue tetrazolium (NBT) fructosamine assay. Serum proteins were separated by agarose gel electrophoresis and stained with NBT to identify individual glycated proteins within the bands. Gels were scanned by densitometry at 525 nm and the glycated protein content was calculated with reference to the total glycated protein content of the sample.


RESULTS
Diabetic cats with increased total fructosamine concentrations had higher concentrations of glycated albumin and glycated alpha- and beta-lipoproteins compared with healthy cats. The concentration of glycated proteins in each of the fractions had a positive linear association with the total glycated protein content of serum, but there was large variation in the relative contributions of the 3 protein fractions to the total glycated protein concentration.


CONCLUSIONS
Based on the results of this study, measurement of individual glycated fractions does not seem to offer any potential diagnostic advantage over measurement of total glycated protein (fructosamine) concentration alone. In some diabetic and healthy cats, glycated lipoproteins formed the major part of the total glycated protein, whereas in other cats albumin was the major contributor.
Martin
G J
GJ
Centre for Companion Animal Health, School of Veterinary Science, The University of Queensland, St Lucia, Australia.
Rand
J S
JS
Hickey
S A
SA
D000818:Animals; D016022:Case-Control Studies; D002371:Cat Diseases / Q000097:blood / Q000175:diagnosis*; D002415:Cats; D003720:Densitometry / Q000379:methods / Q000662:veterinary; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D004587:Electrophoresis, Agar Gel / Q000379:methods / Q000662:veterinary*; D005260:Female; D019270:Fructosamine / Q000097:blood*; D017127:Glycation End Products, Advanced; D007202:Indicators and Reagents; D016014:Linear Models; D008074:Lipoproteins / Q000032:analysis / Q000097:blood; D008297:Male; D009580:Nitroblue Tetrazolium; D012709:Serum Albumin / Q000032:analysis; D000093423:Glycated Serum Albumin
D017127:Glycation End Products, Advanced; D007202:Indicators and Reagents; D008074:Lipoproteins; D012709:Serum Albumin; D009580:Nitroblue Tetrazolium; D019270:Fructosamine; D000093423:Glycated Serum Albumin