Perspectives on using laser fluorescence spectroscopy in chronological skin ageing assessment

Abstract

Laser fluorescence spectroscopy (LFS) is a potential tool for diagnosing pathological skin processes such as fibrosis, hypoxia, and inflammation. This article describes the results of the non-invasive assessment of skin autofluorescence for animals of different ages. The study was performed on outbred white male mice (n = 14). Fluorescence spectra were measured using the multifunctional device LAKK-M (SPE Lazma, Moscow, Russia), which implements LFS in vivo. The method is to record the fluorescence spectrum of a tissue after laser irradiation at a wavelength of λe excites its fluorescence. The wavelength λe is selected corresponding to specific fluorophore properties. To excite the fluorescence, the wavelength λe = 535 nm was used, which made it possible to estimate the fluorescence intensity of the lipofuscin. Increased autofluorescence of lipofuscin in the green waveband was detected in animals in the older age group compared to the younger group using LFS. It is important to note that the autofluorescence spectra of lipofuscin are in superposition with the spectra of other fluorophores and that the autofluorescence spectra of lipofuscin overlap the spectra of other fluorophores such as porphyrins. This may affect the interpretation of LFS data. Adjustment of animal age is necessary for the optical assessment of pathological processes using LFS.