18β-Glycyrrhetinic acid alleviates demyelination by modulating the microglial M1/M2 phenotype in a mouse model of cuprizone-induced demyelination

Neurosci Lett. 2021 Jun 11:755:135871. doi: 10.1016/j.neulet.2021.135871. Epub 2021 Apr 1.

Abstract

This research aimed to examine the nutritious supplementary function of 18β-Glycyrrhetinic acid (18β-GA) in moderating the myelin sheath destruction and behavioral impairments observed in the cuprizone model of demyelination. Mice were fed daily on food containing cuprizone (0.3 %) and given doses of 18β-GA (5 or 1 mg/kg) for a period of five weeks. The groups treated with 18β-GA exhibited improvements in exploratory behavior, locomotive activity, and weight. As assessed using luxol-fast blue and myelin basic protein (MBP) staining, which were used to detect demyelination in the brain, 18β-GA both reduced and prevented instances of cuprizone-induced demyelinating lesions; treatment with 18β-GA also caused the MBP level in the corpus callosum to increase. Furthermore, alongside these positive results following 18β-GA treatment, microglial polarisation was also observed to shift towards the beneficial M2 phenotype. The results of this research thus indicate the potential clinical application of 18β-GA for the prevention of myelin damage and behavioral dysfunction.

Keywords: 18β-Glycyrrhetinic acid; Cuprizone; Demyelination; M1/M2 phenotype.

MeSH terms

  • Animals
  • Cuprizone / toxicity*
  • Demyelinating Diseases / chemically induced*
  • Demyelinating Diseases / drug therapy*
  • Demyelinating Diseases / pathology
  • Glycyrrhetinic Acid / analogs & derivatives*
  • Glycyrrhetinic Acid / pharmacology
  • Glycyrrhetinic Acid / therapeutic use
  • Locomotion / drug effects
  • Locomotion / physiology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Microglia / drug effects*
  • Microglia / pathology
  • Myelin Sheath / drug effects*
  • Myelin Sheath / pathology
  • Phenotype

Substances

  • 18alpha-glycyrrhetinic acid
  • Cuprizone
  • Glycyrrhetinic Acid