Nanoparticle-induced enhancement of cholinesterase activity in the presence of malathion: A potential nerve agent therapeutic

Int J Pharm. 2022 Dec 15:629:122406. doi: 10.1016/j.ijpharm.2022.122406. Epub 2022 Nov 14.

Abstract

Organophosphate nerve agents are associated with assassination, terrorism and chemical warfare, but there has been slow progress in developing a broad-spectrum response to poisoning. For some nerve agents the oxime component of the therapy may not be effective, limiting the effectiveness of emergency treatment that is desperately needed. An alternative therapy may be possible based on accelerating enzyme (acetylcholinesterase) catalysis in unaffected adjacent enzymes. Herein we demonstrate a restoration of acetylcholinesterase activity in malathion-inhibited cell membrane preparations by the administration of functional nanoparticles. The molecularly imprinted polymer nanoparticles were designed to bind selectively to designated enzyme epitopes. Enzyme activity of membrane-bound acetylcholinesterase was measured in the presence of the organophosphate malathion and the selected nanoparticles. Enzymatic acceleration of the cholinesterase was observed at 162 ± 17 % the rate of erythrocyte ghosts without bound nanoparticles. This may restore sufficient acetylcholine hydrolysis to mitigate the effects of poisoning, offsetting the acetylcholine accumulation resulting from enzyme inhibition.

Keywords: Allosteric regulation; Catalysis; Enzyme acceleration; Molecularly imprinted polymers; Nanoparticles; Nerve agents; Organophosphates.

MeSH terms

  • Acetylcholine
  • Acetylcholinesterase
  • Cholinesterases
  • Malathion
  • Nanoparticles*
  • Nerve Agents*

Substances

  • Nerve Agents
  • Malathion
  • Acetylcholinesterase
  • Acetylcholine
  • Cholinesterases