Research Mentor Name

Bruce Berkowitz

Research Mentor Email Address

baberko@med.wayne.edu

Institution / Department

Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine

Document Type

Research Abstract

Research Type

basicbio

Graduate Level Research

no

Abstract

Background: To test for evidence of macula oxidative stress, impaired retinoid handling, and/or photoreceptor energy inefficiencies during healthy human aging as measured by next-generation OCT biomarkers.

Methods: OCT was used to examine light-adapted 20-30 and 70-90-year-old, male and female subjects without overt ophthalmologic disease. Two biomarkers were measured: 1) external limiting membrane (ELM) to retinal pigment epithelium (RPE) contraction, which can arise from oxidative stress-induced acidosis and is concordant with impaired spatial distribution of 11-cis retinal chaperone retinal binding protein 3, and 2) the sub-ELM hyperreflective band profile shape, or Mitochondria Configuration within Photoreceptor inner segments measured with an Aspect Ratio (MCP/AR), which increases with acidosis indicating mitochondrial inefficiencies. The outer nuclear layer (ONL) thickness was also measured.

Results: Compared to younger subjects, healthy older adults—regardless of sex—showed ELM-RPE contraction limited to the fovea and parafovea macula. No changes in MCP/AR or ONL thickness within any region of the macula were noted.

Conclusion: Observation of local acidosis-associated ELM-RPE contraction/impairment in subretinal space water mobility provides evidence for oxidative stress and deficient retinoid distribution within the interphotoreceptor matrix in central macula during healthy aging independent of sex. In contrast, the stability of MCP/AR +/- subretinal space acidosis does not support pan-macula photoreceptor mitochondrial inefficiency in older individuals.

Disciplines

Medicine and Health Sciences

Comments

Supported by grants from the National Institutes of Health [RO1’s AG058171, AG081981, and EY034309], by National Eye Institute Core Grant P30 EY04068, and by an unrestricted grant from Research to Prevent Blindness (Kresge Eye Institute).

Share

COinS