Omarigliptin/galangin combination mitigates lipopolysaccharide-induced neuroinflammation in rats: Involvement of glucagon-like peptide-1, toll-like receptor-4, apoptosis and Akt/GSK-3β signaling

Life Sci. 2022 Apr 15:295:120396. doi: 10.1016/j.lfs.2022.120396. Epub 2022 Feb 11.

Abstract

Aims: The objectives of this work were to assess the possibility of administration of omarigliptin and/or galangin to combat lipopolysaccharide (LPS)-induced neuroinflammation in rats and to explore the possible mechanisms that might contribute to their actions.

Materials and methods: In a rat model of LPS-induced neuroinflammation, the changes in the behavioral tests, biochemical parameters, and the histopathological picture were assessed.

Key findings: Administration of either omarigliptin or galangin to LPS-injected rats was able to significantly improve the behavioral changes with restoration of the oxidant/antioxidant balance, decrement of toll-like receptor-4 levels, and amelioration of the neuroinflammation associated with inhibition of apoptosis and restoration of glucagon-like peptide-1 levels in the cerebral tissues. In addition, omarigliptin and/or galangin significantly reduced the levels of phospho-Akt and glycogen synthase kinase 3 beta (GSK-3β) and significantly increased the expression of beclin-1 in the cerebral tissues compared versus the group treated with LPS alone. As a result, these changes were positively reflected on the histopathological and the electron microscopic picture of the cerebral tissues. These beneficial effects were maximally evidenced in rats treated with omarigliptin/galangin combination relative to the use of either omarigliptin or galangin alone.

Significance: Omarigliptin/galangin combination might be proposed as a promising therapeutic line for mitigation of the pathophysiologic events of LPS-induced neuroinflammation.

Keywords: Galangin; Lipopolysaccharide; Neuroinflammation; Omarigliptin; Rats.

MeSH terms

  • Animals
  • Apoptosis / physiology
  • Drug Therapy, Combination / methods
  • Flavonoids / metabolism
  • Flavonoids / pharmacology*
  • Glucagon-Like Peptide 1 / metabolism
  • Glycogen Synthase Kinase 3 beta / metabolism
  • Heterocyclic Compounds, 2-Ring / metabolism
  • Heterocyclic Compounds, 2-Ring / pharmacology*
  • Inflammation / pathology
  • Lipopolysaccharides / adverse effects
  • Male
  • Microglia / metabolism
  • Neuroinflammatory Diseases / drug therapy*
  • Neuroinflammatory Diseases / physiopathology
  • Proto-Oncogene Proteins c-akt / metabolism
  • Pyrans / metabolism
  • Pyrans / pharmacology*
  • Rats
  • Rats, Wistar
  • Signal Transduction / drug effects
  • Toll-Like Receptor 4 / metabolism

Substances

  • 2-(2,5-difluorophenyl)-5-(2-(methylsulfonyl)-2,6-dihydropyrrolo(3,4-c)pyrazol-5(4H)-yl)tetrahydro-2H-pyran-3-amine
  • Flavonoids
  • Heterocyclic Compounds, 2-Ring
  • Lipopolysaccharides
  • Pyrans
  • Toll-Like Receptor 4
  • galangin
  • Glucagon-Like Peptide 1
  • Glycogen Synthase Kinase 3 beta
  • Proto-Oncogene Proteins c-akt