Dammarane triterpenes targeting α-synuclein: biological activity and evaluation of binding sites by molecular docking

J Enzyme Inhib Med Chem. 2021 Dec;36(1):154-162. doi: 10.1080/14756366.2020.1851216.

Abstract

Parkinson's disease (PD) is a neurodegenerative disorder that affects adult people whose treatment is palliative. Thus, we decided to test three dammarane triterpenes 1, 1a, 1b, and we determined that 1 and 1a inhibit β-aggregation through thioflavine T rather than 1b. Since compound 1 was most active, we determined the interaction between α-synuclein and 1 at 50 µM (Kd) through microscale thermophoresis. Also, we observed differences in height and diameter of aggregates, and α-synuclein remains unfolded in the presence of 1. Also, aggregates treated with 1 do not provoke neurites' retraction in N2a cells previously induced by retinoic acid. Finally, we studied the potential sites of interaction between 1 with α-synuclein fibrils using molecular modelling. Docking experiments suggest that 1 preferably interact with the site 2 of α-synuclein through hydrogen bonds with residues Y39 and T44.

Keywords: Parkinson’s disease; drug target; natural compounds modifiers; oligomers.

MeSH terms

  • Animals
  • Binding Sites / drug effects
  • Dammaranes
  • Dose-Response Relationship, Drug
  • Magnoliopsida / chemistry
  • Mice
  • Molecular Conformation
  • Molecular Docking Simulation*
  • Protein Aggregates / drug effects
  • Structure-Activity Relationship
  • Triterpenes / chemistry
  • Triterpenes / isolation & purification
  • Triterpenes / pharmacology*
  • Tumor Cells, Cultured
  • alpha-Synuclein / antagonists & inhibitors*
  • alpha-Synuclein / isolation & purification
  • alpha-Synuclein / metabolism

Substances

  • Protein Aggregates
  • Triterpenes
  • alpha-Synuclein

Grants and funding

Alberto Cornejo and Carlos Areche acknowledge Instituto Antártico Chileno (INACH) RT_18-19. Julio Caballero acknowledges funds of FONDECYT Regular # 1170718, Mario Simirgiotis FONDECYT Regular # 1180059, and Francisco Melo FONDECYT Regular # 1201013, and Fondequip EQM130149 and USA2055-042031MH_POSTDOC projects are also acknowledged. Vanessa Torres acknowledges APP-1 2019.