A high-throughput screen to identify inhibitors of SOD1 transcription.
Amyotrophic lateral sclerosis (ALS) is a fatal degenerative motor neuron disease. Approximately 20 percent of familial ALS cases are caused by mutations in the Cu/Zn superoxide dismutase (SOD1) gene. Rodents expressing mutant SOD1 transgenes develop progressive, fatal motor neuron disease and disease onset and progression is dependent on the level of SOD1. We investigated the possibility that a reduction in SOD1 protein may be of therapeutic benefit in ALS and screened 30,000 compounds for inhibition of SOD1 transcription. The most effective inhibitor identified was N-{4-[4-(4-methylbenzoyl)-1-piperazinyl]phenyl}-2-thiophenecarboxamide (Compound ID 7687685), which in PC12 cells showed an EC50 of 10.6 microM for inhibition of SOD1 expression and an LD50 more than 30 microM. This compound was subsequently shown to reduce endogenous SOD1 levels in HeLa cells and to exhibit a modest reduction of SOD1 protein levels in mouse spinal cord tissue. These data suggest that the efficacy of compound 7687685 as an inhibitor of SOD1 gene expression is not likely to be clinically useful, although the strategy reported could be applied broadly to screening for small molecule inhibitors of gene expression.
Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655, USA. Paulwright27@ymail.com
Paul D
PD
Wright
Nicholas
N
Wightman
Mickey
M
Huang
Alexandra
A
Weiss
Peter C
PC
Sapp
Gregory D
GD
Cuny
Adrian J
AJ
Ivinson
Marcie A
MA
Glicksman
Robert J
RJ
Ferrante
Wayne
W
Matson
Samantha
S
Matson
Robert H
RH
Brown
D000818:Animals; D015153:Blotting, Western; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D016716:PC12 Cells; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D051381:Rats; D013329:Structure-Activity Relationship; D013482:Superoxide Dismutase / Q000235:genetics*; D000072105:Superoxide Dismutase-1; D014158:Transcription, Genetic / Q000187:drug effects*
C000606290:SOD1 protein, human; C000606291:Sod1 protein, mouse; C000606292:Sod1 protein, rat; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1