Piplartine attenuates aminoglycoside-induced TRPV1 activity and protects from hearing loss in mice

Sci Transl Med. 2024 Aug 7;16(759):eadn2140. doi: 10.1126/scitranslmed.adn2140. Epub 2024 Aug 7.

Abstract

Hearing loss is a major health concern in our society, affecting more than 400 million people worldwide. Among the causes, aminoglycoside therapy can result in permanent hearing loss in 40% to 60% of patients receiving treatment, and despite these high numbers, no drug for preventing or treating this type of hearing loss has yet been approved by the US Food and Drug Administration. We have previously conducted high-throughput screenings of bioactive compounds, using zebrafish as our discovery platform, and identified piplartine as a potential therapeutic molecule. In the present study, we expanded this work and characterized piplartine's physicochemical and therapeutic properties. We showed that piplartine had a wide therapeutic window and neither induced nephrotoxicity in vivo in zebrafish nor interfered with aminoglycoside antibacterial activity. In addition, a fluorescence-based assay demonstrated that piplartine did not inhibit cytochrome C activity in microsomes. Coadministration of piplartine protected from kanamycin-induced hair cell loss in zebrafish and protected hearing function, outer hair cells, and presynaptic ribbons in a mouse model of kanamycin ototoxicity. Last, we investigated piplartine's mechanism of action by phospho-omics, immunoblotting, immunohistochemistry, and molecular dynamics experiments. We found an up-regulation of AKT1 signaling in the cochleas of mice cotreated with piplartine. Piplartine treatment normalized kanamycin-induced up-regulation of TRPV1 expression and modulated the gating properties of this receptor. Because aminoglycoside entrance to the inner ear is, in part, mediated by TRPV1, these results suggested that by regulating TRPV1 expression, piplartine blocked aminoglycoside's entrance, thereby preventing the long-term deleterious effects of aminoglycoside accumulation in the inner ear compartment.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoglycosides* / toxicity
  • Animals
  • Animals, Genetically Modified
  • Female
  • Hearing Loss* / chemically induced
  • Hearing Loss* / genetics
  • Hearing Loss* / metabolism
  • Hearing Loss* / prevention & control
  • Male
  • Mice
  • Models, Molecular
  • Molecular Structure
  • Phosphorylation
  • Piperidones* / chemistry
  • Piperidones* / pharmacology
  • Protein Structure, Tertiary
  • Signal Transduction / drug effects
  • TRPV Cation Channels* / chemistry
  • TRPV Cation Channels* / genetics
  • TRPV Cation Channels* / metabolism
  • Zebrafish
  • Zebrafish Proteins / chemistry
  • Zebrafish Proteins / genetics
  • Zebrafish Proteins / metabolism

Substances

  • piperlongumine
  • Piperidones
  • TRPV1 protein, mouse
  • TRPV1 protein, zebrafish
  • TRPV Cation Channels
  • Zebrafish Proteins
  • Aminoglycosides