Synthesis and evaluation of tetrahydroisoquinoline-benzimidazole hybrids as multifunctional agents for the treatment of Alzheimer's disease

Eur J Med Chem. 2019 Apr 1:167:133-145. doi: 10.1016/j.ejmech.2019.02.008. Epub 2019 Feb 4.

Abstract

A novel series of tetrahydroisoquinoline-benzimidazole hybrids have been designed and synthesized as multifunctional agents against Alzheimer's disease (AD). These compounds were evaluated for their inhibition of neuroinflammation and human β-secretase (hBACE1), and neuroprotective activity. Among them, compound BD3 possessed significant anti-neuroinflammatory activity (IC50 = 5.07 μM against nitric oxide production) through inhibiting the expression and secretion of proinflammatory cytokines in BV2 cells. Compound BD3 also exhibited moderate hBACE1 inhibitory activity (65.7% inhibition at 20 μM) and potent neuroprotective effect by increasing GSH level and reducing ROS production (91.8% cell viability at 5 μM). Parallel artificial membrane permeation assay demonstrated that BD3 could cross the blood-brain barrier (BBB). Thus, this study demonstrates that the compounds with tetrahydroisoquinoline-benzimidazole scaffold are potential anti-AD agents, and they are worth for the further development.

Keywords: Alzheimer's disease; Anti-neuroinflammation; BACE1 inhibition; Neuroprotection; Tetrahydroisoquinoline-benzimidazole hybrids.

MeSH terms

  • Alzheimer Disease / drug therapy*
  • Amyloid Precursor Protein Secretases / antagonists & inhibitors
  • Animals
  • Aspartic Acid Endopeptidases / antagonists & inhibitors
  • Benzimidazoles / chemistry
  • Benzimidazoles / pharmacology
  • Benzimidazoles / therapeutic use*
  • Cell Line
  • Cell Membrane Permeability
  • Drug Design*
  • Glutathione / drug effects
  • Glutathione / metabolism
  • Humans
  • Inflammation / drug therapy
  • Mice
  • Neuroprotective Agents / pharmacology
  • Reactive Oxygen Species / metabolism
  • Tetrahydroisoquinolines / chemistry
  • Tetrahydroisoquinolines / pharmacology
  • Tetrahydroisoquinolines / therapeutic use*

Substances

  • Benzimidazoles
  • Neuroprotective Agents
  • Reactive Oxygen Species
  • Tetrahydroisoquinolines
  • Amyloid Precursor Protein Secretases
  • Aspartic Acid Endopeptidases
  • BACE1 protein, human
  • Glutathione