title: The chemically synthesized ageladine A-derivative LysoGlow84 stains lysosomes in viable mammalian brain cells and specific structures in the marine flatworm Macrostomum lignano.
abstract: Based on the chemical structure and the known chemical synthesis of the marine sponge alkaloid ageladine A, we synthesized the ageladine A-derivative 4-(naphthalene-2-yl)-1H-imidazo[4,5-c]pyridine trifluoroacetate (LysoGlow84). The two-step synthesis started with the Pictet-Spengler reaction of histamine and naphthalene-2-carbaldehyde to a tetrahydropyridine intermediate, which was dehydrogenated with activated manganese (IV) oxide to LysoGlow84. Structure and purity of the synthesized LysoGlow84 were confirmed by NMR spectroscopy and mass spectrometry. The fluorescence intensity emitted by LysoGlow84 depended strongly on the pH of the solvent with highest fluorescence intensity recorded at pH 4. The fluorescence maximum (at 315 nm excitation) was observed at 440 nm. Biocompatibility of LysoGlow84 was investigated using cultured rat brain astrocytes and the marine flatworm Macrostomum lignano. Exposure of the astrocytes for up to 6 h to micromolar concentrations of LysoGlow84 did not compromise cell viability, as demonstrated by several viability assays, but revealed a promising property of this compound for staining of cellular vesicles. Conventional fluorescence microscopy as well as confocal scanning microscopy of LysoGlow84-treated astrocytes revealed co-localization of LysoGlow84 fluorescence with that of LysoTracker® Red DND-99. LysoGlow84 stained unclear structures in Macrostomum lignano, which were identified as lysosomes by co-staining with LysoTracker. Strong fluorescence staining by LysoGlow84 was further observed around the worms' anterior gut and the female genital pore which were not counterstained by LysoTracker Red. Thus, LysoGlow84 is a new promising dye that stains lysosomes and other acidic compartments in cultured cells and in worms.
authors: Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany. Thorsten.Mordhorst@awi.de.|Marnas Biochemicals GmbH, Parkstraße 5, Bremerhaven 27580, Germany. Thorsten.Mordhorst@awi.de.
authors: Thorsten
authors: T
authors: Mordhorst
authors: Center for Biomolecular Interactions, Faculty 2 (Biology/Chemistry), University of Bremen, PO. Box 330440, Bremen 28334, Germany. sush01wal@gmail.com.
authors: Sushil
authors: S
authors: Awal
authors: Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany. Jordan.Sebastian@gmx.de.|Hochschule Bremerhaven, An der Karlstadt 8, Bremerhaven 27568, Germany. Jordan.Sebastian@gmx.de.
authors: Sebastian
authors: S
authors: Jordan
authors: Center for Biomolecular Interactions, Faculty 2 (Biology/Chemistry), University of Bremen, PO. Box 330440, Bremen 28334, Germany. petters@uni-bremen.de.
authors: Charlotte
authors: C
authors: Petters
authors: Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany. linda_sartoris@web.de.|Freie Universität Berlin, Institut für Biologie, Schwendenerstr. 1, Berlin 14195, Germany. linda_sartoris@web.de.
authors: Linda
authors: L
authors: Sartoris
authors: Center for Biomolecular Interactions, Faculty 2 (Biology/Chemistry), University of Bremen, PO. Box 330440, Bremen 28334, Germany. ralf.dringen@uni-bremen.de.
authors: Ralf
authors: R
authors: Dringen
authors: Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany. Ulf.Bickmeyer@awi.de.
authors: Ulf
authors: U
authors: Bickmeyer
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000648:ultrastructure*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004396:Coloring Agents; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D008247:Lysosomes / Q000187:drug effects*; D013058:Mass Spectrometry; D008422:Materials Testing; D018613:Microscopy, Confocal / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods; D010986:Platyhelminths / Q000648:ultrastructure*; D011758:Pyrroles / Q000138:chemical synthesis*; D051381:Rats; D017208:Rats, Wistar
chemical_list: C482289:Ageladine A; D004396:Coloring Agents; D005456:Fluorescent Dyes; D007202:Indicators and Reagents; D011758:Pyrroles