Silencing PAQR3 protects against oxygen-glucose deprivation/reperfusion-induced neuronal apoptosis via activation of PI3K/AKT signaling in PC12 cells

Life Sci. 2021 Jan 15:265:118806. doi: 10.1016/j.lfs.2020.118806. Epub 2020 Nov 26.

Abstract

Aims: Neuronal apoptosis acts as the pivotal pathogenesis of cerebral ischemia/reperfusion (I/R) injury after ischemic stroke. PAQR3 (progestin and adipoQ receptor family member 3) is a crucial player who participates in the regulation of cell death. We aim to explore the specific function and the underlying mechanism of PAQR3 in cerebral I/R induced neuronal injury.

Main methods: We established a mouse middle cerebral artery occlusion/reperfusion (MCAO/R) model and rat adrenal pheochromocytoma (PC12) cell oxygen-glucose deprivation/reperfusion (OGD/R) model to detect the expression and of PAQR3 after I/R treatment in vivo and in vitro. We used lentivirus to knockdown PAQR3 and investigated the function of PAQR3 in I/R induced neuronal apoptosis.

Key findings: PAQR3 expression is markedly increased in the ischemic hemisphere of C57BL/6 mice and PC12 cells after I/R stimulation. Knockdown PAQR3 can attenuate neuronal apoptosis induced by I/R in PC12 cells and exerts neuroprotective effects. PAQR3 deficiency can significantly raise cell viability and suppress LDH leakage under I/R treatment. Silencing PAQR3 attenuates neuronal apoptosis remarkably with fewer TUNEL-positive cells and lower apoptosis rate under I/R treatment. Mechanistically, knockdown of PAQR3 can inhibit the apoptosis pathway through inducing anti-apoptotic proteins and inhibiting pro-apoptotic proteins. Besides, PI3K/AKT signaling suppression with LY294002 abolished the neuroprotective functions induced by silencing PAQR3.

Significance: Our results elucidate that silencing PAQR3 can protect PC12 from OGD/R injury via activating PI3K/AKT pathway. And therefore, provide a novel therapeutic target for the prevention of cerebral I/R injury.

Keywords: Apoptosis; Ischemia reperfusion injury; Ischemic stroke; Neuroprotection; PAQR3.

MeSH terms

  • Animals
  • Apoptosis / physiology
  • Brain Ischemia / genetics
  • Brain Ischemia / metabolism*
  • Brain Ischemia / prevention & control
  • Cell Hypoxia / physiology
  • Gene Silencing / physiology
  • Glucose / deficiency*
  • Intracellular Signaling Peptides and Proteins / biosynthesis*
  • Intracellular Signaling Peptides and Proteins / deficiency
  • Intracellular Signaling Peptides and Proteins / genetics
  • Male
  • Membrane Proteins / biosynthesis*
  • Membrane Proteins / deficiency
  • Membrane Proteins / genetics
  • Mice
  • Mice, Inbred C57BL
  • Neurons / metabolism
  • PC12 Cells
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Rats
  • Reperfusion Injury / genetics
  • Reperfusion Injury / metabolism*
  • Reperfusion Injury / prevention & control

Substances

  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • RKTG protein, mouse
  • Proto-Oncogene Proteins c-akt
  • Glucose