Age-related macular degeneration (AMD) is the leading cause of blindness among older adults in the developed world. While the pathological mechanism(s) have not been definitively elucidated, we hypothesize that defects in the mitochondria are a key event in AMD progression. The goal of the current proposal is to utilize our unique resource of human donor tissue, phenotyped for the presence and severity of AMD, and genotyped for AMD risk alleles, to investigate how and why the mitochondria are damaged with AMD. Based on our preliminary results, this study will focus on donors harboring the AMD risk SNP (rs1061170; amino acid change Y402H) for complement factor H (CFH) since this group demonstrated significantly more mtDNA damage. Pre-selecting this subpopulation should increase our ability to detect significant changes in the RPE proteome, thus providing a more refined elucidation of AMD disease mechanism and potential new targets for therapeutic intervention aimed at preventing AMD development and/or slowing disease progression. The ultimate goal is to minimize vision loss in AMD patients.
Aim 1 will utilize state-of-the-art technology (8-plex iTRAQ protein labeling, Orbitrap Velos Mass Spectrometer, Protein Pilot peptide analysis) to evaluate the mitochondrial and non-mito proteome in donors harboring either WT (TT) or homozygous risk (CC) alleles for CFH.
Aim 2 will determine the sites of failure in processes associated with maintenance of mitochondrial homeostasis by examining the content of proteins involved in mitochondrial biogenesis, fission/fusion, and autophagic removal of damaged mitochondria in human donor RPE. Immunohistochemistry and TEM of retinal sections from genotyped donors will determine if localization of key mt proteins or mt characteristics are altered in a genotype or disease-dependent manner. The proposed studies will provide novel information that is pertinent for developing ?personalized medicine? for AMD patients using state-of-the-art analytical methods and well-characterized donor tissue to reveal the molecular details responsible for AMD-associated mitochondrial dysfunction.
The impending health epidemic of age-related macular degeneration (AMD) creates an urgent need to improve AMD prevention and treatment strategies. This proposal will test the hypothesis that defects in the mitochondria are a key event in AMD progression for individuals harboring the AMD risk SNP (rs1061170; amino acid change Y402H) for complement factor H (CFH), the most prevalent AMD patient population with the greatest risk for developing advanced disease. The goal is to identify potential therapeutic options that would target the primary defect and be administered at an early stage of AMD.
| Fisher, Cody R; Ferrington, Deborah A (2018) Perspective on AMD Pathobiology: A Bioenergetic Crisis in the RPE. Invest Ophthalmol Vis Sci 59:AMD41-AMD47 |
| Ferrington, Deborah A; Ebeling, Mara C; Kapphahn, Rebecca J et al. (2017) Altered bioenergetics and enhanced resistance to oxidative stress in human retinal pigment epithelial cells from donors with age-related macular degeneration. Redox Biol 13:255-265 |
