Microtubule-mediated GLUT4 trafficking is disrupted in insulin resistant skeletal muscle
- University of Copenhagen, Denmark
- Novo Nordisk, Denmark
- Polytechnique Montréal, Canada
- École Polytechnique Fédérale de Lausanne, Switzerland
Abstract
Microtubules serve as tracks for long-range intracellular trafficking of glucose transporter 4 (GLUT4), but the role of this process in skeletal muscle and insulin resistance is unclear. Here, we used fixed and live-cell imaging to study microtubule-based GLUT4 trafficking in human and mouse muscle fibers and L6 rat muscle cells. We found GLUT4 localized on the microtubules in mouse and human muscle fibers. Pharmacological microtubule disruption using Nocodazole (Noco) prevented long-range GLUT4 trafficking and depleted GLUT4-enriched structures at microtubule nucleation sites in a fully reversible manner. Using a perifused muscle-on-a-chip system to enable real-time glucose uptake measurements in isolated mouse skeletal muscle fibers, we observed that Noco maximally disrupted the microtubule network after 5 min without affecting insulin-stimulated glucose uptake. In contrast, a 2h Noco treatment markedly decreased insulin responsiveness of glucose uptake. Insulin resistance in mouse muscle fibers induced either in vitro by C2 ceramides or in vivo by diet-induced obesity, impaired microtubule-based GLUT4 trafficking. Transient knockdown of the microtubule motor protein kinesin-1 protein KIF5B in L6 muscle cells reduced insulin-stimulated GLUT4 translocation while pharmacological kinesin-1 inhibition in incubated mouse muscles strongly impaired insulin-stimulated glucose uptake. Thus, in adult skeletal muscle fibers, the microtubule network is essential for intramyocellular GLUT4 movement, likely functioning to maintain an insulin-responsive cell-surface recruitable GLUT4 pool via kinesin-1 mediated trafficking.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files
Article and author information
Author details
Thomas Elbenhardt Jensen
Funding
Novo Nordisk Fonden (15182)
- Thomas Elbenhardt Jensen
Novo Nordisk Fonden (16OC0023046)
- Jørgen FP Wojtaszewski
Novo Nordisk Fonden (17SA0031406)
- Jonas R Knudsen
Novo Nordisk Fonden (17SA0031406)
- Carlos Henriquez-Olguin
Lundbeckfonden (R313-2019-643)
- Thomas Elbenhardt Jensen
Lundbeckfonden (R266-2017-4358)
- Jørgen FP Wojtaszewski
Sundhed og Sygdom, Det Frie Forskningsråd (FSS8020-00288B)
- Jørgen FP Wojtaszewski
Sundhed og Sygdom, Det Frie Forskningsråd (#9058-00047B)
- Jonas R Knudsen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experiments were approved by the Danish Animal Experimental Inspectorate or by the local animal experimentation committee of the Canton de Vaud under license 2890 and complied with the European Union legislation as outlined by the European Directive 2010/63/EU. The current work adheres to the standards outlined in the ARRIVE reporting guidelines.
Human subjects: The work involving human subjects was approved by the Copenhagen Ethics Committee (H-6-2014-038; Copenhagen, Denmark) and complied with the guidelines of the 2013 Declaration of Helsinki. Informed written consent was obtained from all subjects prior to entering the study.
Copyright
© 2023, Knudsen 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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Microtubule-mediated GLUT4 trafficking is disrupted in insulin resistant skeletal muscle
eLife 12:e83338.
https://doi.org/10.7554/eLife.83338
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