Metabolite therapy guided by liquid biopsy proteomics delays retinal neurodegeneration

Katherine J. Wert, Gabriel Velez, Vijaya L. Kanchustambham, Vishnu Shankar, Lucy P. Evans, Jesse D. Sengillo, Richard N. Zare, Alexander G. Bassuk, Stephen H. Tsang, Vinit B. Mahajan

Research output: Contribution to journalArticle

2 Scopus citations

Abstract

Background: Neurodegenerative diseases are incurable disorders caused by progressive neuronal cell death. Retinitis pigmentosa (RP) is a blinding neurodegenerative disease that results in photoreceptor death and progresses to the loss of the entire retinal network. We previously found that proteomic analysis of the adjacent vitreous served as way to indirectly biopsy the retina and identify changes in the retinal proteome. Methods: We analyzed protein expression in liquid vitreous biopsies from autosomal recessive (ar)RP patients with PDE6A mutations and arRP mice with Pde6ɑ mutations. Proteomic analysis of retina and vitreous samples identified molecular pathways affected at the onset of photoreceptor death. Based on affected molecular pathways, arRP mice were treated with a ketogenic diet or metabolites involved in fatty-acid synthesis, oxidative phosphorylation, and the tricarboxylic acid (TCA) cycle. Findings: Dietary supplementation of a single metabolite, ɑ-ketoglutarate, increased docosahexaeonic acid levels, provided neuroprotection, and enhanced visual function in arRP mice. A ketogenic diet delayed photoreceptor cell loss, while vitamin B supplementation had a limited effect. Finally, desorption electrospray ionization mass spectrometry imaging (DESI-MSI) on ɑ-ketoglutarate-treated mice revealed restoration of metabolites that correlated with our proteomic findings: uridine, dihydrouridine, and thymidine (pyrimidine and purine metabolism), glutamine and glutamate (glutamine/glutamate conversion), and succinic and aconitic acid (TCA cycle). Interpretation: This study demonstrates that replenishing TCA cycle metabolites via oral supplementation prolongs retinal function and provides a neuroprotective effect on the photoreceptor cells and inner retinal network. Funding: NIH grants [R01EY026682, R01EY024665, R01EY025225, R01EY024698, R21AG050437, P30EY026877, 5P30EY019007, R01EY018213, F30EYE027986, T32GM007337, 5P30CA013696], NSF grant CHE-1734082.

Original languageEnglish (US)
Article number102636
JournalEBioMedicine
Volume52
DOIs
StatePublished - Feb 2020
Externally publishedYes

Keywords

  • Desorption electrospray ionization mass spectrometry
  • Ketogenic diet
  • Metabolite supplementation
  • Metabolomics
  • TCA cycle
  • ɑ-ketoglutarate

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'Metabolite therapy guided by liquid biopsy proteomics delays retinal neurodegeneration'. Together they form a unique fingerprint.

  • Cite this

    Wert, K. J., Velez, G., Kanchustambham, V. L., Shankar, V., Evans, L. P., Sengillo, J. D., Zare, R. N., Bassuk, A. G., Tsang, S. H., & Mahajan, V. B. (2020). Metabolite therapy guided by liquid biopsy proteomics delays retinal neurodegeneration. EBioMedicine, 52, [102636]. https://doi.org/10.1016/j.ebiom.2020.102636