Characterization of aneurysmal aortas by biochemical, thermal, and dielectric techniques

Valérie Samouillan (1) , Jany Dandurand (1) , Colette Lacabanne (1) , Andréa Stella , Mauro Gargiulo , Annamaria Degani (2) , Alessandro Gandaglia (2) , Michel Spina (2)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 Unipd - Università degli Studi di Padova = University of Padua

Abdominal aortic aneurysms (AAA) are characterized by structural alterations of the aortic wall resulting from the degradation of elastic fibres and an increase of collagen/elastin ratio. In this study we investigated the chain dynamics of AAA tissues by two techniques generally used for the characterization of polymers, Differential scanning calorimetry (DSC) and thermally stimulated currents (TSC), and we correlated the obtained data with biochemical analyses. The thermal denaturation of collagen observed by DSC allowed us to evaluate the thermal stability of the triple helix domain: notable modifications were evidenced between collagen from control tissue and collagen from AAA, particularly concerning the thermal denaturation. The dielectric analysis of pathologic aortic walls by TSC revealed a relevant change of collagen mobility in AAA, with the occurrence of a specific mode of relaxation between −60 and −40°C. Biochemical, thermal, and dielectric results are compatible with increase of new collagen deposition and/or impairment of the collagen phase stability in the extracellular matrix of AAAs.

Mots clés: Collagen denaturation -Relaxation mode; Chain dynamic; Thermal analysis; Aneurysm

Domaines: Matériaux; Matériaux

Valérie Samouillan, Jany Dandurand, Colette Lacabanne, Andréa Stella, Mauro Gargiulo, et al.. Characterization of aneurysmal aortas by biochemical, thermal, and dielectric techniques. Journal of Biomedical Materials Research Part A, 2010, 95A (2), pp.611-619. ⟨10.1002/jbm.a.32835⟩. ⟨hal-03474555⟩