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Updated: May 22, 2026
07:11
Examination of Anatomical Features of Retinal Ganglion Cells Under N-methyl-D-aspartic Acid (NMDA)-induced Excitotoxicity
Published on: September 19, 2025
PGC-1α negatively regulates extrasynaptic NMDAR activity and excitotoxicity
Clare Puddifoot1, Marc-Andre Martel, Francesc X Soriano
1Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom.
Summary
Reduced PGC-1α (coactivator) expression increases extrasynaptic NMDAR activity, contributing to Huntington
Area of Science:
- Neuroscience
- Molecular Biology
- Genetics
Background:
- PGC-1α (transcriptional coactivator) underexpression is linked to neurodegenerative diseases like Huntington's Disease (HD).
- HD progression involves imbalanced NMDAR activity, specifically increased extrasynaptic NMDAR (NMDAR(EX)) activity.
Purpose of the Study:
- To investigate the role of PGC-1α in controlling NMDAR(EX) activity.
- To determine if PGC-1α suppression contributes to mutant Huntingtin (mHtt)-induced excitotoxicity in HD.
Main Methods:
- Knock-down of endogenous PGC-1α in rat cortical neurons.
- Exogenous expression of PGC-1α in neurons.
- Expression of mutant Huntingtin (mHtt) and wild-type Huntingtin (Htt) in neurons.
- Assessment of NMDAR(EX) activity and vulnerability to NMDA excitotoxicity.
Main Results:
- PGC-1α knock-down increased NMDAR(EX) activity and excitotoxic vulnerability.
- Exogenous PGC-1α reduced NMDAR(EX) currents and conferred neuroprotection.
- mHtt expression selectively increased NMDAR(EX) activity and excitotoxicity.
- mHtt and PGC-1α knockdown effects were nonadditive, suggesting a common pathway.
- Exogenous PGC-1α reversed mHtt-induced NMDAR(EX) hyperactivity and protected neurons.
Conclusions:
- PGC-1α regulates neuronal NMDAR(EX) activity.
- PGC-1α underexpression contributes to mHtt-induced excitotoxicity in HD models.
- Targeting PGC-1α levels may offer a therapeutic strategy for reducing aberrant NMDAR(EX) activity in related disorders.
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