Photocrosslinking of Adventitial Collagen in the Porcine Abdominal Aorta: A Preliminary Approach to a Strategy for Prevention of Aneurysmal Rupture

摘要

This study was aimed at generating data for designing a potential method to preventthe rupture of the abdominal aortic aneurysm (AAA). We found that the mechanical strength andstiffness of blood vessel walls was enhanced by the crosslinking of adventitial collagen through aphotochemical process promoted by ultraviolet-A (UV-A) radiation. The experiments were carried outon samples isolated from 25 normal porcine aortas. The adventitial layer was separated from the otherlayers and exposed to UV radiation of 365-nm wavelength, in the presence of a riboflavin compoundas the photosensitizer. Mechanical testing of 30 specimens, prior to and after exposure, indicatedan increase in both strength (ultimate stress) and stiffness (Young’s modulus) of the adventitialspecimens following irradiation. The crosslinking process also led to an enhanced resistance toexperimental collagenolysis, as determined on six specimens. At this phase of conceptual design, wesuggest that by applying this method to an aneurysmal dilated wall region, the stabilization of tunicaadventitia may delay or prevent the rupture of the aneurysm and, with further investigation andrefinement, can become a therapeutic strategy for arresting the progression of AAA.