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Analyses of Mitochondrial Calcium Influx in Isolated Mitochondria and Cultured Cells
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Analyses of Mitochondrial Calcium Influx in Isolated Mitochondria and Cultured Cells

Published on: April 27, 2018

Mitochondrial calcium uniporter Mcu controls excitotoxicity and is transcriptionally repressed by neuroprotective

Jing Qiu1, Yan-Wei Tan, Anna M Hagenston

  • 1Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK.

Nature Communications
|June 19, 2013
PubMed

Insights

The mitochondrial calcium uniporter (Mcu) gene drives excitotoxicity by increasing mitochondrial calcium uptake. Inhibiting Mcu expression protects neurons from excitotoxic cell death, offering therapeutic potential for neurological disorders.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Molecular Biology

Background:

  • Neuronal excitotoxicity is a major contributor to brain damage in various neurological disorders.
  • Mitochondrial calcium uptake plays a critical role in regulating neuronal function and survival.
  • The mitochondrial calcium uniporter (Mcu) is a key regulator of mitochondrial calcium influx.

Purpose of the Study:

  • To investigate the role of the mitochondrial calcium uniporter (Mcu) in neuronal excitotoxicity.
  • To elucidate the mechanisms by which Mcu influences mitochondrial calcium levels and cell death.
  • To explore the potential of targeting Mcu for therapeutic interventions in excitotoxic disorders.

Main Methods:

  • Exogenous expression and knockdown of Mcu in neuronal models.
  • Measurement of mitochondrial calcium levels and membrane potential.
  • NMDA receptor activation and assessment of excitotoxic cell death.
  • Investigation of transcriptional regulation of Mcu expression via Npas4.

Main Results:

  • Exogenous Mcu expression enhanced NMDA-induced mitochondrial calcium uptake, depolarization, and excitotoxic cell death.
  • Knockdown of endogenous Mcu reduced mitochondrial calcium overload and conferred resistance to excitotoxicity.
  • Synaptic activity transcriptionally repressed Mcu expression through Npas4, limiting mitochondrial calcium uptake.
  • This adaptive mechanism prevented excitotoxic death by inhibiting excessive mitochondrial calcium influx.

Conclusions:

  • Mcu is a critical determinant of neuronal excitotoxicity by mediating mitochondrial calcium uptake.
  • The Npas4-mediated transcriptional repression of Mcu represents an adaptive mechanism to prevent excitotoxic cell death.
  • Mcu and its regulatory pathways are potential therapeutic targets for excitotoxic neurological disorders.

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