Previous studies have shown that biomechanical analysis of aorta from
diabetic subjects reveals a marked increase in stiffness compared to a
orta from age-matched control subjects. In the present paper we have p
roposed that this increased stiffness can be attributed to glycation-i
nduced inter-molecular cross-links based on a direct analysis of the t
wo known glycation cross-links, the fluorescent pentosidine and the no
n-fluorescent NFC-1. There was a sig nificant difference in the increa
se in concentration of both cross-links with increasing age for both t
he intima (p < 0.0025) and the media (p < 0.0005) from the diabetic co
mpared to the control subjects, but no correlation with the mature enz
ymic cross-link hydroxylysyl-pyridinoline. Finally, we have obtained a
significant correlation of stiffness with both glycation cross-links
(NFC-1, r = 0.86; p < 0.005 and pentosidine r = 0.75, p < 0.05), but t
he concentration of NFC-1 is about 50 times greater than that of pento
sidine, indicating that it is the major glycation crosslink responsibl
e for the stiffening of the aorta.