title: Cytotoxicity of chloral-derived beta-carbolines is not specific towards neuronal nor dopaminergic cells.
abstract: beta-Carbolines structurally related to the selective dopaminergic neurotoxin 1-methyl-4- phenylpyridinium (MPP(+)) may contribute to dopaminergic neurodegeneration in Parkinson's disease. The chloral-derived mammalian alkaloid derivative 1-trichloromethyl-1,2,3,4-tetrahydro-beta-carboline (TaClo) is formed endogenously by a Pictet-Spengler condensation from the biogenic amine tryptamine (Ta) and the hypnotic aldehyde chloral (Clo). Here we examine the dopaminergic toxicity of TaClo and related compounds by testing their differential cytotoxicities in dopaminergic SH-SY5Y and non-dopaminergic murine Neuro2A neuroblastoma cell lines as well as in heterologous expression systems of the dopamine transporter (DAT) using both HEK-293 and Neuro2A cells. All TaClo derivatives showed significant cytotoxicity in all cell lines after 72 hours with the following rank order of toxic potency: 1-Tribromomethyl-1,2,3,4-tetrahydro-beta-carboline (TaBro) > TaClo > MPP(+) > 1,2,3,4-tetrahydro-beta-carboline (THbetaC) > 2[N]-methyl-TaClo > 2[N]-methyl-THbetaC. In contrast to MPP(+), there was no selectivity towards dopaminergic cells or cells ectopically expressing the DAT in vitro. Our results suggest that TaClo and related analogs are strong cytotoxins without selectivity towards dopaminergic cells.
authors.affiliation: Department of Neurology, Technical University of Dresden, Dresden, Germany. alexander.storch@neuro.med.tu-dresden.de
authors.forename: A
authors.initials: A
authors.lastname: Storch
authors.forename: Y-I
authors.initials: YI
authors.lastname: Hwang
authors.forename: G
authors.initials: G
authors.lastname: Bringmann
authors.forename: D
authors.initials: D
authors.lastname: Feineis
authors.forename: S
authors.initials: S
authors.lastname: Ott
authors.forename: R
authors.initials: R
authors.lastname: Brückner
authors.forename: J
authors.initials: J
authors.lastname: Schwarz
mesh_terms: D015655:1-Methyl-4-phenylpyridinium / Q000633:toxicity; D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology; D002243:Carbolines / Q000633:toxicity*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003627:Data Interpretation, Statistical; D004298:Dopamine / Q000502:physiology*; D015259:Dopamine Agents / Q000633:toxicity; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism; D006801:Humans; D020267:MPTP Poisoning / Q000473:pathology; D051379:Mice; D009447:Neuroblastoma / Q000473:pathology; D009474:Neurons / Q000187:drug effects* / Q000473:pathology; D010879:Piperazines / Q000494:pharmacology
chemical_list: D002243:Carbolines; D015259:Dopamine Agents; D050483:Dopamine Plasma Membrane Transport Proteins; D010879:Piperazines; C043425:vanoxerine; D015655:1-Methyl-4-phenylpyridinium; D004298:Dopamine