Biochemical adaptations of the retina and retinal pigment epithelium support a metabolic ecosystem in the vertebrate eye
- University of Washington, United States
- West Virginia University, United States
Abstract
Here we report multiple lines of evidence for a comprehensive model of energy metabolism in the vertebrate eye. Metabolic flux, locations of key enzymes, and our finding that glucose enters mouse and zebrafish retinas mostly through photoreceptors support a conceptually new model for retinal metabolism. In this model, glucose from the choroidal blood passes through the retinal pigment epithelium to the retina where photoreceptors convert it to lactate. Photoreceptors then export the lactate as fuel for the retinal pigment epithelium and for neighboring Müller glial cells. We used human retinal epithelial cells to show that lactate can suppress consumption of glucose by the retinal pigment epithelium. Suppression of glucose consumption in the retinal pigment epithelium can increase the amount of glucose that reaches the retina. This framework for understanding metabolic relationships in the vertebrate retina provides new insights into the underlying causes of retinal disease and age-related vision loss.
Article and author information
Author details
Michelle M Giarmarco
Funding
National Eye Institute (EY06641)
- James B Hurley
National Eye Institute (EY017863)
- James B Hurley
National Eye Institute (EY026030)
- Jianhai Du
- Jennifer R Chao
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal research was authorized by the University of Washington Institutional Animal Care and Use Committee.
Copyright
© 2017, Kanow et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Biochemical adaptations of the retina and retinal pigment epithelium support a metabolic ecosystem in the vertebrate eye
eLife 6:e28899.
https://doi.org/10.7554/eLife.28899
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