TY - JOUR
T1 - Glycosylation of human abumin in diabetes mellitus
T2 - Extensive microheterogeneity of serum and urinary species as revealed by isoelectric focusing
AU - Candiano, Giovanni
AU - Ghiggeri, Gian Marco
AU - Delfino, Gerolamo
AU - Queirolo, Carlo
AU - Gianazza, Elisabetta
AU - Righetti, Pier Giorgio
PY - 1984
Y1 - 1984
N2 - Albumin and glycosylated albumin from serum and urine of 10 diabetic patients have been studied by ultrathin‐layer isoelectric focusing andsilver staining. Both total serum albumin and its glycosylated form were microheterogeneous with a main band focused in the pH 4–5 range; in the case of glycosylated ablumin several cathodic bands with pI's up to 7 were found to form a discretely abundant population among the total species. Some similarites and some striking differences were observed for urinary albumin, which, beside the main unmodified albumin with pI ca. 4.8, was enriched in microheteregeneous more anodal bands (PI 4.0–4.7 species). All these anodal bands were tightly bound by concanavalin A‐Sepharose, suggesting their identity as glycosylatedalbumin. these observations indicate that the glycosylation of albumin is not an equimolar reaction, but it can involve many sites of attachement of carbohydrates. The also suggest that albumin species with higher net negative charge and higher content of carbohydrates are preferentially able to pass through the glomerular barrier, providing the descriptive basis of diabetic albuminuria. Their relevance to diabetic nephropathy is a goal for further work.
AB - Albumin and glycosylated albumin from serum and urine of 10 diabetic patients have been studied by ultrathin‐layer isoelectric focusing andsilver staining. Both total serum albumin and its glycosylated form were microheterogeneous with a main band focused in the pH 4–5 range; in the case of glycosylated ablumin several cathodic bands with pI's up to 7 were found to form a discretely abundant population among the total species. Some similarites and some striking differences were observed for urinary albumin, which, beside the main unmodified albumin with pI ca. 4.8, was enriched in microheteregeneous more anodal bands (PI 4.0–4.7 species). All these anodal bands were tightly bound by concanavalin A‐Sepharose, suggesting their identity as glycosylatedalbumin. these observations indicate that the glycosylation of albumin is not an equimolar reaction, but it can involve many sites of attachement of carbohydrates. The also suggest that albumin species with higher net negative charge and higher content of carbohydrates are preferentially able to pass through the glomerular barrier, providing the descriptive basis of diabetic albuminuria. Their relevance to diabetic nephropathy is a goal for further work.
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U2 - 10.1002/elps.1150050406
DO - 10.1002/elps.1150050406
M3 - Article
AN - SCOPUS:84988097417
VL - 5
SP - 217
EP - 222
JO - Electrophoresis
JF - Electrophoresis
SN - 0173-0835
IS - 4
ER -