PGC-1α Affects Epileptic Seizures by Regulating Mitochondrial Fusion in Epileptic Rats

Neurochem Res. 2023 May;48(5):1361-1369. doi: 10.1007/s11064-022-03834-3. Epub 2022 Dec 1.

Abstract

Background: Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), regulated by AMPK, is an important regulator of mitochondrial fusion. At present, whether the AMPK/PGC-1α signaling pathway regulates mitochondrial dynamics in epileptic rats is still unknown.

Methods: Adult male Sprague-Dawley (SD) rats were randomly divided into fourgroups: the control group (0.9% saline, n = 5), the EP groups (lithium-pilocarpine was used to induce epilepsy, and tissues were harvested at 6 and 24 h, every time point, n = 5), the EP + Compound C group (the specific inhibitor of PGC-1α, 15 mg/kg in 2% DMSO, n = 5), and the EP + DMSO group (0.9% saline + 2% DMSO, n = 5). To investigate whether PGC-1α participates in seizures by regulating the expression of mitofusin1/2(MFN1/2)in rats.

Results: In this study, the behavioral results indicate that the seizure susceptibility of the rats to epilepsy was increased when the expression of PGC-1α was inhibited. Subsequently, Western blot results suggested that the expression level of both MFN1 and MFN2 in the hippocampus was higher at 6 and 24 h after an epileptic seizure. Besides, the expression of PGC-1α and MFN2 was significantly decreased in the hippocampus when the epileptic rats were treated with Compound C. Furthermore, the immunofluorescence analysis of the localization of MFN1/2 and PGC-1α showed that MFN1/2 was mainly expressed in neurons but not astrocytes in the hippocampus and cerebral cortex of rats. Meanwhile, PGC-1α colocalized with the excitatory post-synaptic marker PSD95, suggesting that PGC-1α may regulate the seizure susceptibility of the rats by mediating excitatory post-synaptic signaling.

Conclusion: The AMPK/PGC-1α signaling pathway may play an important role in the lithium-pilocarpine-induced epileptic rat model by mediating the expression of fusion proteins.

Keywords: AMPK; Compound C; Epilepsy; MFN1/2; PGC-1α.

MeSH terms

  • AMP-Activated Protein Kinases / metabolism
  • Animals
  • Dimethyl Sulfoxide
  • Epilepsy* / chemically induced
  • Lithium
  • Male
  • Mitochondrial Dynamics*
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / metabolism
  • Pilocarpine
  • Rats
  • Rats, Sprague-Dawley
  • Saline Solution
  • Seizures / chemically induced

Substances

  • AMP-Activated Protein Kinases
  • Dimethyl Sulfoxide
  • Lithium
  • Pilocarpine
  • Saline Solution
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha