Screening for insulin-independent pathways that modulate glucose homeostasis identifies androgen receptor antagonists
- Max Planck Institute for Heart and Lung Research, Germany
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Austria
Abstract
Pathways modulating glucose homeostasis independently of insulin would open new avenues to combat insulin resistance and diabetes. Here, we report the establishment, characterization and use of a vertebrate 'insulin-free' model to identify insulin-independent modulators of glucose metabolism. insulin knockout zebrafish recapitulate core characteristics of diabetes and survive only up to larval stages. Utilizing a highly efficient endoderm transplant technique, we generated viable chimeric adults that provide the large numbers of insulin mutant larvae required for our screening platform. Using glucose as a disease-relevant readout, we screened 2233 molecules and identified 3 that consistently reduced glucose levels in insulin mutants. Most significantly, we uncovered an insulin-independent beneficial role for androgen receptor antagonism in hyperglycemia, mostly by reducing fasting glucose levels. Our study proposes therapeutic roles for androgen signaling in diabetes and, more broadly, offers a novel in vivo model for rapid screening and decoupling of insulin-dependent and -independent mechanisms.
Data availability
Microarray and RNA-Seq data have been deposited in the ArrayExpress database at EMBL-EBI (www.ebi.ac.uk/arrayexpress) under accession number E-MTAB-7282 and E-MTAB-7283 respectively.
Article and author information
Author details
Didier YR Stainier
Funding
Max-Planck-Gesellschaft (Open-access funding)
- Sri Teja Mullapudi
- Christian SM Helker
- Giulia LM Boezio
- Hans-Martin Maischein
- Anna M Sokol
- Stefan Guenther
- Hiroki Matsuda
- Johannes Graumann
- Yu Hsuan Carol Yang
- Didier YR Stainier
Deutsches Zentrum für Herz-Kreislaufforschung
- Anna M Sokol
- Johannes Graumann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Zebrafish husbandry was performed under standard conditions in accordance with institutional (MPG) and national ethical and animal welfare guidelines approved by the ethics committee for animal experiments at the Regierungspräsidium Darmstadt, Germany (permit numbers B2/1017, B2/1041, B2/1089, B2/1138 and B2/Anz. 1007).
Copyright
© 2018, Mullapudi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Screening for insulin-independent pathways that modulate glucose homeostasis identifies androgen receptor antagonists
eLife 7:e42209.
https://doi.org/10.7554/eLife.42209
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