title: Thermal transitions of fibrillar collagen unveiled by second-harmonic generation microscopy of corneal stroma.
abstract: The thermal transitions of fibrillar collagen are investigated with second-harmonic generation polarization anisotropy microscopy. Second-harmonic generation images and polarization anisotropy profiles of corneal stroma heated in the 35-80°C range are analyzed by means of a theoretical model that is suitable to probe principal intramolecular and interfibrillar parameters of immediate physiological interest. Our results depict the tissue modification with temperature as the interplay of three destructuration stages at different hierarchical levels of collagen assembly including its tertiary structure and interfibrillar alignment, thus supporting and extending previous findings. This method holds the promise of a quantitative inspection of fundamental biophysical and biochemical processes and may find future applications in real-time and postsurgical functional imaging of collagen-rich tissues subjected to thermal treatments.
authors.affiliation: Institute of Applied Physics "Nello Carrara", National Research Council, Sesto Fiorentino, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Matteini
authors.forename: Riccardo
authors.initials: R
authors.lastname: Cicchi
authors.forename: Fulvio
authors.initials: F
authors.lastname: Ratto
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kapsokalyvas
authors.forename: Francesca
authors.initials: F
authors.lastname: Rossi
authors.forename: Marella
authors.initials: M
authors.lastname: de Angelis
authors.forename: Francesco S
authors.initials: FS
authors.lastname: Pavone
authors.forename: Roberto
authors.initials: R
authors.lastname: Pini
mesh_terms: D000818:Animals; D003094:Collagen / Q000737:chemistry*; D003319:Corneal Stroma / Q000378:metabolism*; D008853:Microscopy; D008958:Models, Molecular; D011487:Protein Conformation; D011489:Protein Denaturation; D013552:Swine; D013696:Temperature
chemical_list: D003094:Collagen