Analysis of human aorta using fluorescence lifetime imaging (FLIM)

VIERIA DAMIANI G; ADUR J; PEIXOTO FERRO D; ADAM R; PELEGATI VB; DE THOMAZ AA; CESAR CL; METZE K

Conferencia; 2012 Photonics West; 2012

The use of photonics has improved our understanding of biologic phenomena. For the study of the normal and pathologic architecture of the aorta the use ofTwo-Photon Excited Fluorescence (TPEF) and Second Harmonic Generation showed interesting details of morphologic changes ofthe elastin-collagen architecture during aging or development of hypertension in previousstudies. In this investigation we tried to apply fluorescence lifetime imaging (FLIM) for the morphologic analysis of human aortas. The aim of our study was to use FLIM in non-stained formalin-fixed and paraffin-embedded samples of the aorta ascendants in hypertensive and normotensive patients of various ages,examining two different topographical regions. The FLIM-spectra of collagen and elastic fibers were clearly distinguishable, thus permitting an exact analysis of unstained material on the microscopic level. Moreover the FLIM spectrum of elastic fibers revealed variations between individual cases, which indicate modifications on a molecular level and might be related to FLIM age or diseases states and reflect modifications on a molecular level.