Assessment of the aortic wall histological changes with ageing

Aim: The authors aimed to quantitatively assess the variation with age of three of the main components of the aortic wall, namely elastic fibers (FE) and collagen fibers [FC(COL)], and smooth muscle cells (SMCs). Materials and Methods: Four aortic cross sections (base, cross, thoracic, abdominal) were collected during autopsy from 90 cases of all ages, processed using the classical histopathological (HP) technique (formalin fixation and paraffin embedding) and stained with Orcein and Goldner’s trichrome. The obtained histological slides were transformed into virtual slides. Quantitative measurements of the three components were made on identical regions of interest (ROIs) selected from two-paired slides stained with the above-mentioned techniques using custom-made software, developed in MATLAB (MathWorks, USA). Results and Discussions: FE revealed an obvious decreasing general trend with age, present at all four levels of investigation. Smooth muscle fibers (FM) density showed almost no variation with age regardless of the level at which the measurement was made. FC(COL) density had an obvious increasing trend with age, expressed in all four aortic regions FE densities and FM densities were higher in men than in women, while FC(COL) densities were higher in women than in men in three of the aortic regions excepting, in all cases, the cross region. Conclusions: There were differences between men and women concerning the composition of aortic wall cellular and extracellular compartments. FE and FC(COL) dominated the age-related remodeling process of the aortic wall. The process evolved in the same way in all regions of the aorta. Studies need to be continued to define more clearly this complex process of vascular wall remodeling with aging.