Activation of spinal PGC-1α regulates microglial polarization through a feedback loop between ROS-mediated

Yanhua Chen1, Guoxu Ling1, Qingling Xu1

  • 1Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, PR China.

PubMed
Abstract

Insights

Activating PPARγ coactivator-1α (PGC-1α) ameliorates neuropathic pain by modulating microglial polarization. This involves a feedback loop between reactive oxygen species (ROS)-mediated mitochondrial dysfunction and the NLRP3 inflammasome, shifting microglia from M2 to M1 phenotype.

Area of Science:

  • Neuroscience
  • Immunology
  • Molecular Biology

Background:

  • Microglial polarization imbalance contributes to neuropathic pain pathogenesis.
  • PPARγ coactivator-1α (PGC-1α) influences microglial polarization, but mechanisms are unclear.

Purpose of the Study:

  • To investigate PGC-1α's role in microglial polarization via a feedback loop involving reactive oxygen species (ROS)-mediated mitochondrial dysfunction and the NLRP3 inflammasome in a rat model of chronic constriction injury (CCI).

Main Methods:

  • Pain behavior quantification, immunofluorescence for microglial markers (CD68, ARG1, IBA1), Western blotting, qPCR for mitochondrial DNA, ROS measurement (DHE), SOD and MDA assays, and ELISA for cytokine levels (TNF-α, IL-1β, IL-6, IL-10).

Main Results:

  • CCI rats exhibited ROS-mediated mitochondrial dysfunction, NLRP3 inflammasome activation, and a shift from M2 to M1 microglial phenotype.
  • A feedback loop was identified where ROS-mediated mitochondrial dysfunction activates NLRP3 inflammasome, which in turn exacerbates ROS production and mitochondrial dysfunction.
  • PGC-1α activation modulated this feedback loop, shifting microglial phenotype.

Conclusions:

  • Activation of PGC-1α shows potential as a therapeutic strategy for neuropathic pain.
  • The study elucidates a novel feedback mechanism between mitochondrial dysfunction and the NLRP3 inflammasome in neuropathic pain.