Cardanol-derived AChE inhibitors: Towards the development of dual binding derivatives for Alzheimer's disease

Eur J Med Chem. 2016 Jan 27:108:687-700. doi: 10.1016/j.ejmech.2015.12.024. Epub 2015 Dec 17.

Abstract

Cardanol is a phenolic lipid component of cashew nut shell liquid (CNSL), obtained as the byproduct of cashew nut food processing. Being a waste product, it has attracted much attention as a precursor for the production of high-value chemicals, including drugs. On the basis of these findings and in connection with our previous studies on cardanol derivatives as acetylcholinesterase (AChE) inhibitors, we designed a novel series of analogues by including a protonable amino moiety belonging to different systems. Properly addressed docking studies suggested that the proposed structural modifications would allow the new molecules to interact with both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE, thus being able to act as dual binding inhibitors. To disclose whether the new molecules showed the desired profile, they were first tested for their cholinesterase inhibitory activity towards EeAChE and eqBuChE. Compound 26, bearing an N-ethyl-N-(2-methoxybenzyl)amine moiety, showed the highest inhibitory activity against EeAChE, with a promising IC50 of 6.6 μM, and a similar inhibition profile of the human isoform (IC50 = 5.7 μM). As another positive feature, most of the derivatives did not show appreciable toxicity against HT-29 cells, up to a concentration of 100 μM, which indicates drug-conform behavior. Also, compound 26 is capable of crossing the blood-brain barrier (BBB), as predicted by a PAMPA-BBB assay. Collectively, the data suggest that the approach to obtain potential anti-Alzheimer drugs from CNSL is worth of further pursuit and development.

Keywords: Acetylcholinesterase; Alzheimer's disease; Cashew nut shell liquid; Dual binding site AChE inhibitors; Multitarget compounds.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / enzymology
  • Binding Sites / drug effects
  • Cholinesterase Inhibitors / chemical synthesis
  • Cholinesterase Inhibitors / chemistry
  • Cholinesterase Inhibitors / pharmacology*
  • Cholinesterases / metabolism*
  • Dose-Response Relationship, Drug
  • HT29 Cells
  • Humans
  • Molecular Structure
  • Phenols / chemical synthesis
  • Phenols / chemistry
  • Phenols / pharmacology*
  • Structure-Activity Relationship

Substances

  • Cholinesterase Inhibitors
  • Phenols
  • cardanol
  • Cholinesterases