Sustained PGC-1α2 or PGC-1α3 expression induces astrocyte dysfunction and degeneration

Eur J Cell Biol. 2024 Mar;103(1):151377. doi: 10.1016/j.ejcb.2023.151377. Epub 2023 Nov 19.

Abstract

Peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) transcriptional coactivators are key regulators of energy metabolism-related genes and are expressed in energy-demanding tissues. There are several PGC-1α variants with different biological functions in different tissues. The brain is one of the tissues where the role of PGC-1α isoforms remains less explored. Here, we used a toxin-based mouse model of Parkinson's disease (PD) and observed that the expression levels of variants PGC-1α2 and PGC-1α3 in the nigrostriatal pathway increases at the onset of dopaminergic cell degeneration. This increase occurs concomitant with an increase in glial fibrillary acidic protein levels. Since PGC-1α coactivators regulate cellular adaptive responses, we hypothesized that they could be involved in the modulation of astrogliosis induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Therefore, we analysed the transcriptome of astrocytes transduced with expression vectors encoding PGC-1α1 to 1α4 by massively parallel sequencing (RNA-seq) and identified the main cellular pathways controlled by these isoforms. Interestingly, in reactive astrocytes the inflammatory and antioxidant responses, adhesion, migration, and viability were altered by PGC-1α2 and PGC-1α3, showing that sustained expression of these isoforms induces astrocyte dysfunction and degeneration. This work highlights PGC-1α isoforms as modulators of astrocyte reactivity and as potential therapeutic targets for the treatment of PD and other neurodegenerative disorders.

Keywords: Adhesion; Astrocyte reactivity; Isoforms; Migration; PGC-1α; PGC-1α2; PGC-1α3; Parkinson’s disease; Variants; Viability.

MeSH terms

  • Animals
  • Astrocytes* / metabolism
  • Brain / metabolism
  • Dopamine / metabolism
  • Mice
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / genetics
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / metabolism
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Transcription Factors* / genetics
  • Transcription Factors* / metabolism

Substances

  • Transcription Factors
  • Protein Isoforms
  • Dopamine
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha