High-Throughput Cell-Based Screening Using Scintillation Proximity Assay for the Discovery of Inositol Phosphatase Inhibitors

Abstract

Inositol monophosphatase is a potential drug target for developing lithium-mimetic agents for the treatment of bipolar disorder. Enzyme-based assays have been traditionally used in compound screening to identify inositol monophosphatase inhibitors. A cell-based screening assay in which the compound needs to cross the cell membrane before reaching the target enzyme offers a new approach for discovering novel structure leads of the inositol monophosphatase inhibitor. The authors have recently reported a high-throughput measurement of G-protein-coupled receptor activation by determining inositol phosphates in cell extracts using scintillation proximity assay. This cell-based assay has been modified to allow the determination of inositol monophosphatase activity instead of G-protein-coupled receptors. The enzyme is also assayed in its native form and physiological environment. The authors have applied this cell-based assay to the high-throughput screening of a large compound collection and identified several novel inositol monophosphatase inhibitors. (Journal of Biomolecular Screening 2004:132-140)

A Cell-Based Ultra-High-Throughput Screening Assay for Identifying Inhibitors of D-Amino Acid Oxidase

“…Purified enzyme-based screening had failed to identify cell membrane-permeable inhibitors, but a cell-based inositol monophosphatase assay was developed and applied for the HTS of a compound library that identified new leads. 15,16 Because DAO is also an intracellular enzyme, an inhibitor would need to penetrate the cell membrane to reach this target. To accelerate the lead discovery based on compound screening, we have developed and executed the cell-based screening assay for DAO described here.…”

Application of Division Arrest Technology to Cell-Based HTS: Comparison with Frozen and Fresh Cells

“…3 Although in vitro biochemical assays have been used extensively in early drug discovery efforts in the past, there is now a growing trend for the use of cellbased assay in HTS. [4][5][6][7][8][9] The advantages of cell-based screening include (1) functional assays that distinguish between agonists and antagonists, (2) opportunity to identify allosteric modulators, (3) additional direct information on compounds with regards to cell permeability and stability inside cells, (4) assays performed in a more relevant physiological context, and (5) additional information available early on in the drug discovery process with regards to acute cytotoxicity associated with compounds. Therefore, cell-based assays offer a wealth of information and, when applied at the time of HTS, can prove to be useful for early drug discovery efforts while identifying high-quality leads.…”

myo-Inositol Monophosphatase: A Challenging Target for Mood Stabilising Drugs

“…To this end a scintillation proximity assay was developed that directly measured inositol phosphate accumulation in cell extracts and applied it to a high throughput screen [46,47]. To this end a scintillation proximity assay was developed that directly measured inositol phosphate accumulation in cell extracts and applied it to a high throughput screen [46,47].…”

“…Dose response curve for dibenzylsuberone bissulfonylfluoride 5 compared to LiCl measured using the scintillation proximity assay of Brandish et al[46,47].…”