Diabetes, Vol 29, Issue 10 778-781, Copyright © 1980 by American Diabetes Association
Increased collagen cross-linkages in experimental diabetes: reversal by beta-aminopropionitrile and D-penicillamine
K Chang, J Uitto, EA Rowold, GA Grant, C Kilo and JR Williamson
The effects of diabetes on collagen cross-link formation and solubility
were investigated in granulation tissue collagen induced by polyester
fabric implanted subcutaneously in rats at the same time diabetes was
produced by injection of streptozotocin. Thus, all the collagen analyzed
was formed in a diabetic milieu. Ten days later the implants were removed
and the total collagen content as well as the fraction soluble in 0.5 M
acetic acid was determined. Predominantly type I collagen accumulated in
the implants. Total collagen content was the same in diabetics and
controls; however, the acid-soluble fraction in diabetic animals was only
half that of controls (8.5% and 17.7%, respectively), and the ratio of beta
chains to alpha chains in the acid-soluble fraction was higher in diabetics
(0.89) than in controls (0.69). In animals treated with
beta-aminopropionitrile or D-penicillamine the acid-soluble fraction of
collagen from diabetics equaled that from controls. These observations
indicate that both intramolecular and intermolecular cross-links are
increased in type I collagen from diabetic animals. Since these cross-links
interfere with degradation of collagen by collagenase, they may contribute
to accelerated intimal sclerosis of arteries and to capillary basement
membrane thickening in diabetes.