Skin autofluorescence as a clinical tool for non-invasive assessment of advanced glycation end products—clinical significance and influencing factors

Advanced glycation end products (AGEs) are heterogeneous compounds derived from nonenzymatic glycation of free amino groups in proteins, lipids, and nucleic acids. Since AGE formation is significantly increased in a number of pathological conditions, there is a huge interest in exploring cause-and-effect relationships between AGEs, various chronic diseases, and their complications. Due to the high physiological fluctuations in circulating AGEs and the lack of good reproducibility of measurement methods, the possibility to assess tissue AGE accumulation is beneficial. Since skin AGEs exhibit fluorescence properties, they can be measured by skin autofluorescence using an AGE Reader. This is a simple and non-invasive technique that has been validated against the gold standard for measuring tissue AGEs (skin biopsies) in a number of clinical trials. However, some endogenous and exogenous factors may limit the reliability of AGE Reader measurements, with special attention being given to skin phototype and some skin care products