title: Azaphilones inhibit tau aggregation and dissolve tau aggregates in vitro.
abstract: The aggregation of the microtubule-associated protein tau is a seminal event in many neurodegenerative diseases, including Alzheimer's disease. The inhibition or reversal of tau aggregation is therefore a potential therapeutic strategy for these diseases. Fungal natural products have proven to be a rich source of useful compounds having wide varieties of biological activities. We have previously screened Aspergillus nidulans secondary metabolites for their ability to inhibit tau aggregation in vitro using an arachidonic acid polymerization protocol. One aggregation inhibitor identified was asperbenzaldehyde, an intermediate in azaphilone biosynthesis. We therefore tested 11 azaphilone derivatives to determine their tau assembly inhibition properties in vitro. All compounds tested inhibited tau filament assembly to some extent, and four of the 11 compounds had the advantageous property of disassembling preformed tau aggregates in a dose-dependent fashion. The addition of these compounds to the tau aggregates reduced both the total length and number of tau polymers. The most potent compounds were tested in in vitro reactions to determine whether they interfere with tau's normal function of stabilizing microtubules (MTs). We found that they did not completely inhibit MT assembly in the presence of tau. These derivatives are very promising lead compounds for tau aggregation inhibitors and, more excitingly, for compounds that can disassemble pre-existing tau filaments. They also represent a new class of anti-tau aggregation compounds with a novel structural scaffold.
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: Smita R
authors.initials: SR
authors.lastname: Paranjape
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Riley
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: Amber D
authors.initials: AD
authors.lastname: Somoza
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: C Elizabeth
authors.initials: CE
authors.lastname: Oakley
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: Clay C C
authors.initials: CC
authors.lastname: Wang
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Prisinzano
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: Berl R
authors.initials: BR
authors.lastname: Oakley
authors.affiliation: †Department of Molecular Biosciences, ‡Department of Chemistry, ⊥Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States.|§Department of Chemistry, ∥Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, United States.
authors.forename: T Chris
authors.initials: TC
authors.lastname: Gamblin
mesh_terms: D001233:Aspergillus nidulans; D001578:Benzopyrans / Q000138:chemical synthesis / Q000494:pharmacology*; D066298:In Vitro Techniques; D008870:Microtubules / Q000187:drug effects; D010860:Pigments, Biological / Q000138:chemical synthesis / Q000494:pharmacology*; D016875:tau Proteins / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D001578:Benzopyrans; D010860:Pigments, Biological; C494154:azaphilone; D016875:tau Proteins
keywords: Alzheimer’s disease; Aspergillus; Aspergillus nidulans; Tau; aggregation inhibitor; azaphilone; microtubule-associated protein; natural products
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