Use of X-ray diffraction in study of human diabetic and aging collagen.

Extensive investigations of the solubility and fluorescence of collagen fibers in diabetes have revealed that there are significant changes in their physical properties. These changes are associated with increased cross-link formation. We used X-ray diffraction to study these changes in human extensor tendons at a molecular level in relation to both aging and diabetes. Our results indicate that diabetes induces significant alterations in the ultrastructure of collagen in the lateral packing of the molecules and the axial structure of the specimen. These changes can be induced in normal tendon by incubation in ribose and glucose-6-phosphate but are different from those associated with the normal process of aging.