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The Translocator Protein (TSPO) in Mitochondrial Bioenergetics and Immune Processes

Calina Betlazar1,2, Ryan J Middleton1, Richard Banati1,2

  • 1Human Health, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia.

Cells
|February 28, 2020
PubMed

Insights

The translocator protein (TSPO) is a biomarker for neuroinflammation. Emerging research suggests TSPO is crucial for cellular energy and immune responses in microglia, shifting focus from cholesterol transport.

Area of Science:

  • Neuroinflammation research
  • Mitochondrial biology
  • Innate immunity

Background:

  • Translocator protein (TSPO) is an outer mitochondrial membrane protein.
  • TSPO is a widely used biomarker for neuroinflammation, upregulated in activated microglia.
  • Its precise cellular functions are debated, challenging traditional roles in steroidogenesis.

Purpose of the Study:

  • To review experimental literature on the immunomodulatory effects of TSPO.
  • To highlight TSPO's central role in mitochondrial processes and bioenergetics.
  • To examine TSPO's involvement in modulating reactive oxygen species (ROS) and inflammatory responses.

Main Methods:

  • Review of experimental literature.
  • Analysis of studies on TSPO's immunomodulatory effects.
  • Examination of research on TSPO's role in mitochondrial function and bioenergetics.

Main Results:

  • Evidence disputes TSPO's primary role in cholesterol transport and steroidogenesis.
  • Growing evidence supports TSPO's fundamental role in cellular bioenergetics and mitochondrial function.
  • TSPO is implicated in innate immune processes of microglia and modulation of ROS.

Conclusions:

  • A paradigm shift is occurring in understanding TSPO's cellular functions.
  • TSPO plays a critical role in microglial immune responses and mitochondrial bioenergetics.
  • Future research should focus on TSPO's involvement in energy metabolism and inflammation.
Keywords:
microgliamitochondrianeuroinflammationreactive oxygen speciestranslocator protein

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