Dnmt3a is an epigenetic mediator of adipose insulin resistance
- University of California, Berkeley, United States
- Lund University, Sweden
- Beth Israel Deaconess Medical Center, United States
- Broad Institute, United States
- Weill Cornell Medical College, United States
- University of Copenhagen, Denmark
Abstract
Insulin resistance results from an intricate interaction between genetic make-up and environment, and thus may be orchestrated by epigenetic mechanisms like DNA methylation. Here, we demonstrate that DNA methyltransferase 3a (Dnmt3a) is both necessary and sufficient to mediate insulin resistance in cultured mouse and human adipocytes. Furthermore, adipose-specific Dnmt3a knock-out mice are protected from diet-induced insulin resistance and glucose intolerance without accompanying changes in adiposity. Unbiased gene profiling studies revealed Fgf21 as a key negatively regulated Dnmt3a target gene in adipocytes with concordant changes in DNA methylation at the Fgf21 promoter region. Consistent with this, Fgf21 can rescue Dnmt3a-mediated insulin resistance, and DNA methylation at the FGF21 locus was elevated in human subjects with diabetes and correlated negatively with expression of FGF21 in human adipose tissue. Taken together, our data demonstrate that adipose Dnmt3a is a novel epigenetic mediator of insulin resistance in vitro and in vivo.
Article and author information
Author details
Funding
American Heart Association (15SDG25240017)
- Sona Kang
National Institutes of Health (102173)
- Evan D Rosen
National Institutes of Health (102170)
- Evan D Rosen
National Institutes of Health (85171)
- Evan D Rosen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All animal work was approved by the BIDMC IACUC (056-2017) and/or the UC Berkeley ACUC (AUP-2015-08-7887).
Copyright
© 2017, You 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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Dnmt3a is an epigenetic mediator of adipose insulin resistance
eLife 6:e30766.
https://doi.org/10.7554/eLife.30766
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