title: Sialic acid, diabetes, and aging: a study on the erythrocyte membrane.
abstract: Sialic acid (SA) content and Na+/K+-ATPase activity of red blood cell (RBC) membranes were studied in 26 normoalbuminuric patients with insulin-dependent diabetes mellitus (IDDM), 25 normoalbuminuric patients with non-insulin-dependent diabetes mellitus (NIDDM), and 40 healthy nondiabetic subjects with a negative family history for diabetes. A decrease in RBC membrane SA content and Na+/K+-ATPase activity was observed in older control subjects compared with younger controls. A significant correlation between age, Na+/K+-ATPase activity, and SA content was also found. No difference was observed in RBC membrane SA content between IDDM and NIDDM subjects, but Na+/K+-ATPase activity was significantly lower in IDDM patients. SA content was increased in NIDDM subjects compared with healthy subjects of similar age, whereas Na+/K+-ATPase activity was significantly lower in both IDDM and NIDDM subjects compared with controls. In NIDDM, Na+/K+-ATPase activity was significantly correlated with age, whereas both Na+/K+-ATPase activity and SA content were significantly correlated in IDDM and NIDDM patients. Hemoglobin A1c, (HbA1c) levels did not show any significant correlation either with Na+/K+-ATPase or with SA content in diabetic patients. The modified SA content and Na+/K+-ATPase activity in elderly subjects described in the present study indicate a similar behavior of the erythrocyte membrane during both RBC senescence and aging of subjects.
authors.affiliation: Institute of Biochemistry, School of Medicine, University of Ancona, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Mazzanti
authors.forename: R A
authors.initials: RA
authors.lastname: Rabini
authors.forename: E
authors.initials: E
authors.lastname: Salvolini
authors.forename: M
authors.initials: M
authors.lastname: Tesei
authors.forename: D
authors.initials: D
authors.lastname: Martarelli
authors.forename: B
authors.initials: B
authors.lastname: Venerando
authors.forename: G
authors.initials: G
authors.lastname: Curatola
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood* / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000378:metabolism; D004910:Erythrocyte Membrane / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D019158:N-Acetylneuraminic Acid / Q000032:analysis* / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis / Q000378:metabolism
chemical_list: D006442:Glycated Hemoglobin; D019158:N-Acetylneuraminic Acid; D000254:Sodium-Potassium-Exchanging ATPase