title: Development and implementation of a high-throughput compound screening assay for targeting disrupted ER calcium homeostasis in Alzheimer's disease.
abstract: Disrupted intracellular calcium homeostasis is believed to occur early in the cascade of events leading to Alzheimer's disease (AD) pathology. Particularly familial AD mutations linked to Presenilins result in exaggerated agonist-evoked calcium release from endoplasmic reticulum (ER). Here we report the development of a fully automated high-throughput calcium imaging assay utilizing a genetically-encoded FRET-based calcium indicator at single cell resolution for compound screening. The established high-throughput screening assay offers several advantages over conventional high-throughput calcium imaging technologies. We employed this assay for drug discovery in AD by screening compound libraries consisting of over 20,000 small molecules followed by structure-activity-relationship analysis. This led to the identification of Bepridil, a calcium channel antagonist drug in addition to four further lead structures capable of normalizing the potentiated FAD-PS1-induced calcium release from ER. Interestingly, it has recently been reported that Bepridil can reduce Aβ production by lowering BACE1 activity. Indeed, we also detected lowered Aβ, increased sAPPα and decreased sAPPβ fragment levels upon Bepridil treatment. The latter findings suggest that Bepridil may provide a multifactorial therapeutic modality for AD by simultaneously addressing multiple aspects of the disease.
authors.affiliation: Department of Translational Brain Research, DZNE - German Center for Neurodegenerative Diseases, Munich, Germany ; Center for Neuropathology and Prion Research; Ludwig Maximilian University, Munich, Germany ; Graduate School of Systemic Neurosciences, Ludwig Maximilian University, Munich, Germany.
authors.forename: Kamran
authors.initials: K
authors.lastname: Honarnejad
authors.forename: Alexander
authors.initials: A
authors.lastname: Daschner
authors.forename: Armin
authors.initials: A
authors.lastname: Giese
authors.forename: Andrea
authors.initials: A
authors.lastname: Zall
authors.forename: Boris
authors.initials: B
authors.lastname: Schmidt
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szybinska
authors.forename: Jacek
authors.initials: J
authors.lastname: Kuznicki
authors.forename: Jochen
authors.initials: J
authors.lastname: Herms
mesh_terms: D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism*; D016229:Amyloid beta-Peptides / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D002217:Carbachol / Q000494:pharmacology; D002460:Cell Line; D055808:Drug Discovery; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism*; D057166:High-Throughput Screening Assays / Q000379:methods; D006706:Homeostasis / Q000187:drug effects*; D006801:Humans; D057054:Molecular Imaging / Q000379:methods; D009154:Mutation; D053764:Presenilin-1 / Q000235:genetics / Q000378:metabolism; D053766:Presenilin-2 / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D054852:Small Molecule Libraries
chemical_list: D016229:Amyloid beta-Peptides; D015220:Calcium Channels; D053764:Presenilin-1; D053766:Presenilin-2; D054852:Small Molecule Libraries; D002217:Carbachol; D002118:Calcium