Reactive glycosylation endproducts in diabetic uraemia and treatment of renal failure.
In diabetes and ageing, glucose-derived advanced glycosylation endproducts (AGEs) cross-link proteins and cause vascular tissue damage. Elimination of circulating low-molecular weight AGE-modified molecules (LMW-AGEs) by the kidney is impaired in diabetic patients with end-stage renal disease, a group subject to accelerated atherosclerosis. We determined the effectiveness of current renal replacement treatments on elimination of serum LMW-AGEs in diabetic and non-diabetic patients with end-stage renal disease. Although diabetic patients receiving high-flux haemodialysis achieved 33% lower steady-state serum LMW-AGE than did those in conventional haemodialysis (p < 0.005), LMW-AGE concentrations remained 3.5-6 fold above normal, whether high-flux dialysis, conventional haemodialysis, or chronic ambulatory peritoneal dialysis were used. High-flux haemodialysis markedly reduced AGE during each treatment session (47.9% in the diabetic, p < 0.001 and 60.6% in the non-diabetic group, p < 0.001) but concentrations returned to pre-treatment range within 3 hours. In contrast, normal LMW-AGE concentrations were maintained in patients with functioning renal transplants. We found that LMW-AGEs with an apparent molecular weight of 2000-6000 circulate and retain strong inherent chemical reactivity--when exposed to collagen in vitro, up to 77% attached covalently to form AGE-collagen, and the AGE-crosslink inhibitor aminoguanidine completely inhibited this reaction. The results suggest that LMW-AGEs comprise a set of chemically-reactive molecules that are refractory to removal by current dialysis treatments. Through covalent reattachment onto vascular matrix or serum components, LMW-AGEs may exacerbate vascular pathology associated with end-stage renal disease.
Makita
Z
Z
Picower Institute for Medical Research, Manhasset, NY 11030.
Bucala
R
R
Rayfield
E J
EJ
Friedman
E A
EA
Kaufman
A M
AM
Korbet
S M
SM
Barth
R H
RH
Winston
J A
JA
Fuh
H
H
Manogue
K R
KR
D000328:Adult; D000368:Aged; D003404:Creatinine / Q000097:blood; D003928:Diabetic Nephropathies / Q000097:blood / Q000628:therapy*; D005260:Female; D017127:Glycation End Products, Advanced / Q000097:blood*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis; D011379:Prognosis; D006435:Renal Dialysis; D014511:Uremia / Q000097:blood* / Q000150:complications
D017127:Glycation End Products, Advanced; D003404:Creatinine