title: Inhibitors of Acetylcholinesterase Derived from 7-Methoxytacrine and Their Effects on the Choline Transporter CHT1.
abstract: Reversible acetylcholinesterase inhibitors are used in Alzheimer disease therapy. However, tacrine and its derivatives have severe side effects. Derivatives of the tacrine analogue 7-methoxytacrine (MEOTA) are less toxic.
  
  
  
  We evaluated new derivatives of 7-MEOTA (2 homodimers linked by 2 C4-C5 chains and 5 N-alkylated C4-C8 side chain derivatives) in vitro, using the rat hippocampal choline transporter CHT1.
  
  
  
  Some derivatives were effective inhibitors of rat acetylcholinesterase and comparable with 7-MEOTA. All derivatives were able to inhibit CHT1, probably via quaternary ammonium, and this interaction could be involved in the enhancement of their detrimental side effects and/or in the attenuation of their promising effects. Under conditions of disrupted lipid rafts, the unfavorable effects of some derivatives were weakened. Only tacrine was probably able to stereospecifically interact with the naturally occurring amyloid-β isoform and to simultaneously stimulate CHT1. Some derivatives, when coincubated with amyloid β, did not influence CHT1. All derivatives also increased the fluidity of the cortical membranes.
  
  
  
  The N-alkylated derivative of 7-MEOTA bearing from C4 side chains appears to be the most promising compound and should be evaluated in future in vivo research.
authors.affiliation: Alzheimer Disease Center, National Institute of Mental Health, Klecany, Czech Republic.
authors.forename: Zdenka
authors.initials: Z
authors.lastname: Kristofikova
authors.forename: Jan
authors.initials: J
authors.lastname: Ricny
authors.forename: Ondrej
authors.initials: O
authors.lastname: Soukup
authors.forename: Jan
authors.initials: J
authors.lastname: Korabecny
authors.forename: Eugenie
authors.initials: E
authors.lastname: Nepovimova
authors.forename: Kamil
authors.initials: K
authors.lastname: Kuca
authors.forename: Daniela
authors.initials: D
authors.lastname: Ripova
mesh_terms: D000478:Alkylation; D016229:Amyloid beta-Peptides / Q000187:drug effects; D000818:Animals; D027682:Cation Transport Proteins / Q000187:drug effects*; D002540:Cerebral Cortex / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D002800:Cholinesterase Inhibitors / Q000138:chemical synthesis* / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008560:Membrane Fluidity / Q000187:drug effects; D021962:Membrane Microdomains / Q000187:drug effects; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013237:Stereoisomerism; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism; D013619:Tacrine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: D016229:Amyloid beta-Peptides; C501512:CHT1 protein, rat; D027682:Cation Transport Proteins; D002800:Cholinesterase Inhibitors; D000644:Quaternary Ammonium Compounds; D013619:Tacrine; C016222:7-methoxytacrine; D002784:Cholesterol; D002794:Choline