Weight loss, insulin resistance, and study design confound results in a meta-analysis of animal models of fatty liver
- University of Cambridge, United Kingdom
- University of Leeds, United Kingdom
Abstract
The classical drug development pipeline necessitates studies using animal models of human disease to gauge future efficacy in humans, however there is a low conversion rate from success in animals to humans. Non-alcoholic fatty liver disease (NAFLD) is a complex chronic disease without any established therapies and a major field of animal research. We performed a meta-analysis with meta-regression of 603 interventional rodent studies (10,364 animals) in NAFLD to assess which variables influenced treatment response. Weight loss and alleviation of insulin resistance were consistently associated with improvement in NAFLD. Multiple drug classes that do not affect weight in humans caused weight loss in animals. Other study design variables, such as age of animals and dietary composition, influenced the magnitude of treatment effect. Publication bias may have increased effect estimates by 37-79%. These findings help to explain the challenge of reproducibility and translation within the field of metabolism.
Data availability
The raw dataset used for analysis, including references to individual studies, are available Figure 1 - Source Data and deposited in the Dryad repository at https://doi.org/10.5061/dryad.pzgmsbcgc.R code used for analysis are available in Supplementary Data.Source data files have been provided for Figures 2-8.
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Data from: Weight loss, insulin resistance, and study design confound results in a meta-analysis of animal models of fatty liverDryad Digital Repository, 10.5061/dryad.pzgmsbcgc.
Article and author information
Author details
Funding
Wellcome Trust (216329/Z/19/Z)
- Jake P Mann
European Society for Paediatric Research (Young Investigator Start-Up Grant)
- Jake P Mann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Joel K Elmquist, University of Texas Southwestern Medical Center, United States
Version history
- Received: March 3, 2020
- Accepted: October 15, 2020
- Accepted Manuscript published: October 16, 2020 (version 1)
- Version of Record published: November 6, 2020 (version 2)
Copyright
© 2020, Hunter 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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Weight loss, insulin resistance, and study design confound results in a meta-analysis of animal models of fatty liver
eLife 9:e56573.
https://doi.org/10.7554/eLife.56573
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