Endo-Lysosome Function in the Retinal Pigment Epithelium in Health and Disease

  • Aparna LakkarajuEmail author
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 723)


Polarized cells such as the retinal pigment epithelium (RPE) have elaborate endo-lysosomal networks that enable them to carry out efficient trafficking and metabolism of proteins and lipids, which is crucial for maintaining cellular homeostasis. Once thought to be little more than garbage disposal systems, late endosomes and lysosomes are now being recognized as highly dynamic platforms for macromolecule sorting, signaling, and cholesterol metabolism. Aging and age-related diseases are characterized by decreased endo-lysosomal function, disturbed cholesterol metabolism, and increased accumulation of lipid–protein aggregates called lipofuscin in postmitotic cells such as neurons and the RPE. Cholesterol accumulation and impaired endo-lysosomal function have emerged as key players in Alzheimer’s and Parkinson’s diseases. This review focuses on recent data supporting a link between endo-lysosome dysfunction, lipofuscin accumulation, and abnormal cholesterol homeostasis in the pathogenesis of age-related macular degeneration (AMD).


Retinal pigment epithelium Age-related macular degeneration Lipofuscin A2E Late endosome Lysosome Cholesterol Protein lipid ­trafficking Niemann–Pick C1 Apolipoprotein 



Supported by grants from the American Health Assistance Foundation (M2009093) and the Karl Kirchgessner Foundation and a career development award from Research to Prevent Blindness


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of Ophthalmology and Visual Sciences, School of Medicine and Public HealthUniversity of Wisconsin-MadisonMadisonUSA

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