MCT2 overexpression rescues metabolic vulnerability and protects retinal ganglion cells in two models of glaucoma

Improving cellular access to energy substrates is one strategy to overcome observed declines in energy production and utilization in the aged and pathologic central nervous system. Monocarboxylate transporters (MCTs), the movers of lactate, pyruvate, and ketone bodies into or out of a cell, are sign...

Full description

Bibliographic Details
Main Authors: Mohammad Harun-Or-Rashid, Nathaniel Pappenhagen, Ryan Zubricky, Lucy Coughlin, Assraa Hassan Jassim, Denise M. Inman
Format: Article
Language:English
Published: Elsevier 2020-07-01
Series:Neurobiology of Disease
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0969996120302199
Description
Summary:Improving cellular access to energy substrates is one strategy to overcome observed declines in energy production and utilization in the aged and pathologic central nervous system. Monocarboxylate transporters (MCTs), the movers of lactate, pyruvate, and ketone bodies into or out of a cell, are significantly decreased in the DBA/2 J mouse model of glaucoma. In order to confirm MCT decreases are disease-associated, we decreased MCT2 in the retinas of MCT2fl/+ mice using an injection of AAV2-cre, observing significant decline in ATP production and visual evoked potential. Restoring MCT2 levels in retinal ganglion cells (RGCs) via intraocular injection of AAV2-GFP-MCT2 in two models of glaucoma, the DBA/2 J (D2), and a magnetic bead model of ocular hypertension (OHT), preserved RGCs and their function. Viral-mediated overexpression of MCT2 increased RGC density and axon number, reduced energy imbalance, and increased mitochondrial function as measured by cytochrome c oxidase and succinate dehydrogenase activity in both models of glaucoma. Ocular hypertensive mice injected with AAV2:MCT2 had significantly greater P1 amplitude as measured by pattern electroretinogram than mice with OHT alone. These findings indicate overexpression of MCT2 improves energy homeostasis in the glaucomatous visual system, suggesting that expanding energy input options for cells is a viable option to combat neurodegeneration.
ISSN:1095-953X