Effects of dexmedetomidine on cognitive dysfunction and neuroinflammation via the HDAC2/HIF-1α/PFKFB3 axis in a murine model of postoperative cognitive dysfunction

J Biochem Mol Toxicol. 2022 Jun;36(6):e23044. doi: 10.1002/jbt.23044. Epub 2022 May 2.

Abstract

Inhibition of histone deacetylase (HDAC) may be a useful approach in the treatment of disorders characterized by cognitive dysfunction. Dexmedetomidine (DEX), an α2-adrenoceptor (α2-AR) agonist, has demonstrated neuroprotective effects. Here, we attempted to investigate the protective effects of DEX on postoperative cognitive dysfunction (POCD) involving HDAC2. Male C57BL/6 mice were selected to develop a POCD model, where HDAC2, HIF-1α, and PFKFB3 expression was quantified. DEX was administered before POCD modeling. Then the cognitive function of POCD mice was evaluated with the open field and Y-maze tests. Meanwhile, lipopolysaccharide (LPS) was employed to induce BV-2 microglial cells to simulate the inflammatory response. The contents of TNF-α, IL-6, and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA) in mouse serum and BV-2 cell supernatant. Abundant expression of HDAC2, HIF-1α, and PFKFB3 was confirmed in POCD mice (p < 0.05). Cognitive dysfunction in POCD mice could be alleviated following pharmacological inhibition of HDAC2 by FK228 (p < 0.05). Mechanistically, HDAC2 upregulated HIF-1α and PFKFB3 and promoted the secretion of inflammatory factors in LPS-exposed BV-2 cells (p < 0.05). DEX attenuated neuroinflammation and the resulting cognitive dysfunction by decreasing HDAC2 expression and HIF-1α-dependent PFKFB3 upregulation in POCD mice (p < 0.05). In conclusion, DEX-regulated HDAC2 may play an inhibitory role in mice with POCD through regulation of the HIF-1α/PFKFB3 axis.

Keywords: HDAC2; HIF-1α; PFKFB3; dexmedetomidine; postoperative cognitive dysfunction.

MeSH terms

  • Animals
  • Cognitive Dysfunction* / drug therapy
  • Cognitive Dysfunction* / etiology
  • Dexmedetomidine* / pharmacology
  • Dexmedetomidine* / therapeutic use
  • Disease Models, Animal
  • Hippocampus / metabolism
  • Histone Deacetylase 2 / metabolism
  • Histone Deacetylase 2 / pharmacology
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Lipopolysaccharides / pharmacology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neuroinflammatory Diseases
  • Phosphofructokinase-2 / metabolism
  • Postoperative Cognitive Complications*

Substances

  • Hif1a protein, mouse
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Lipopolysaccharides
  • Dexmedetomidine
  • PFKFB3 protein, mouse
  • Phosphofructokinase-2
  • Hdac2 protein, mouse
  • Histone Deacetylase 2