Lipofuscin, Its Origin, Properties, and Contribution to Retinal Fluorescence as a Potential Biomarker of Oxidative Damage to the Retina

This narrative review synthesizes preclinical and laboratory evidence on lipofuscin, an autofluorescent pigment accumulating in postmitotic cells like the RPE. The central hypothesis is that oxidation of RPE lipofuscin causes a spectral shift in its fluorescence emission—decreasing yellow-red and increasing blue fluorescence—which could serve as a biomarker for oxidative damage in diseases like age-related macular degeneration (AMD) and Stargardt’s disease. The review discusses the potential utility of imaging these spectral characteristics for monitoring disease progression and evaluating antioxidant therapies. However, it notes that current clinical fluorescence imaging instruments use excitation wavelengths too long to capture the blue emission range where oxidation-induced changes are most pronounced.