title: High-throughput chemical screening identifies AG-490 as a stimulator of aquaporin 2 membrane expression and urine concentration.
abstract: A reduction or loss of plasma membrane aquaporin 2 (AQP2) in kidney principal cells due to defective vasopressin (VP) signaling through the VP receptor causes excessive urine production, i.e., diabetes insipidus. The amount of AQP2 on the plasma membrane is regulated by a balance of exocytosis and endocytosis and is the rate limiting step for water reabsorption in the collecting duct. We describe here a systematic approach using high-throughput screening (HTS) followed by in vitro and in vivo assays to discover novel compounds that enhance vasopressin-independent AQP2 membrane expression. We performed initial chemical library screening with a high-throughput exocytosis fluorescence assay using LLC-PK1 cells expressing soluble secreted yellow fluorescent protein and AQP2. Thirty-six candidate exocytosis enhancers were identified. These compounds were then rescreened in AQP2-expressing cells to determine their ability to increase AQP2 membrane accumulation. Effective drugs were then applied to kidney slices in vitro. Three compounds, AG-490, β-lapachone, and HA14-1 increased AQP2 membrane accumulation in LLC-PK1 cells, and both AG-490 and β-lapachone were also effective in MDCK cells and principal cells in rat kidney slices. Finally, one compound, AG-490 (an EGF receptor and JAK-2 kinase inhibitor), decreased urine volume and increased urine osmolality significantly in the first 2-4 h after a single injection into VP-deficient Brattleboro rats. In conclusion, we have developed a systematic procedure for identifying new compounds that modulate AQP2 trafficking using initial HTS followed by in vitro assays in cells and kidney slices, and concluding with in vivo testing in an animal model.
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Naohiro
authors.initials: N
authors.lastname: Nomura
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Paula
authors.initials: P
authors.lastname: Nunes
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Richard
authors.initials: R
authors.lastname: Bouley
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Anil V
authors.initials: AV
authors.lastname: Nair
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and.
authors.forename: Stanley
authors.initials: S
authors.lastname: Shaw
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and.
authors.forename: Erica
authors.initials: E
authors.lastname: Ueda
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Nutthapoom
authors.initials: N
authors.lastname: Pathomthongtaweechai
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Hua A Jenny
authors.initials: HA
authors.lastname: Lu
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; and Program in Membrane Biology and Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts brown.dennis@mgh.harvard.edu.
authors.forename: Dennis
authors.initials: D
authors.lastname: Brown
mesh_terms: D000818:Animals; D051399:Aquaporin 2 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics; D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism; D004285:Dogs; D005089:Exocytosis / Q000187:drug effects; D057166:High-Throughput Screening Assays; D066298:In Vitro Techniques; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism; D007671:Kidney Concentrating Ability / Q000187:drug effects*; D018374:LLC-PK1 Cells; D008164:Luminescent Proteins / Q000096:biosynthesis / Q000235:genetics; D061985:Madin Darby Canine Kidney Cells; D008856:Microscopy, Fluorescence; D009994:Osmolar Concentration; D021381:Protein Transport; D011910:Rats, Brattleboro; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D013552:Swine; D013997:Time Factors; D014162:Transfection; D020032:Tyrphostins / Q000494:pharmacology*; D015854:Up-Regulation; D064804:Urological Agents / Q000494:pharmacology*
chemical_list: C496025:Aqp2 protein, rat; D051399:Aquaporin 2; D001426:Bacterial Proteins; D008164:Luminescent Proteins; D020032:Tyrphostins; D064804:Urological Agents; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; C054562:yellow fluorescent protein, Bacteria
keywords: EGFR and JAK-2 inhibitor; cell signaling; diabetes insipidus; drug screening; vasopressin; water channels