The hepatic AMPK-TET1-SIRT1 axis regulates glucose homeostasis
- Nanchang University, China
- Gannan Medical University, China
- Beijing Institutes of Life Science, Chinese Academy of Sciences, China
- First Affiliated Hospital of Gannan Medical University, China
- Xiamen University, China
- School of Basic Medical Sciences, Nanchang University, China
Abstract
Ten-eleven translocation methylcytosine dioxygenase 1 (TET1) is involved in multiple biological functions in cell development, differentiation, and transcriptional regulation. Tet1 deficient mice display the defects of murine glucose metabolism. However, the role of TET1 in metabolic homeostasis keeps unknown. Here, our finding demonstrates that hepatic TET1 physically interacts with SIRT1 via its C-terminal and activates its deacetylase activity, further regulating the acetylation-dependent cellular trans-localization of transcriptional factors PGC-1a and FOXO1, resulting in the activation of hepatic gluconeogenic gene expression that includes PPARGC1A, G6PC, and SLC2A4. Importantly, the hepatic gluconeogenic gene activation program induced by fasting is inhibited in Tet1 heterozygous mice livers. The AMPK activators metformin or AICAR-two compounds that mimic fasting-elevate hepatic gluconeogenic gene expression dependent on in turn activation of the AMPK-TET1-SIRT1 axis. Collectively, our study identifies TET1 as a SIRT1 coactivator and demonstrates that the AMPK-TET1-SIRT1 axis represents a potential mechanism or therapeutic target for glucose metabolism or metabolic diseases.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Natural Science Foundation of China (81760160)
- Jianing Zhong
Startup Fund for Scholars of Gannan Medical University (QD201605)
- Jianing Zhong
Innovative Team of Gannan Medical University (TD201708)
- Jianing Zhong
The Open Project of Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education (XN201807)
- Jianing Zhong
JiangXi Provincial Natural Science Foundation (20202BAB206086)
- Jianing Zhong
JiangXi Provincial Natural Science Foundation (20171ACB21001)
- Chunbo Zhang
JiangXi Provincial Natural Science Foundation (20171BCB23029)
- Chunbo Zhang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experiments were conducted in accordance with an approved protocol by the Institutional Animal Care and Ethics Committee of Xiamen University and Nanchang University.
Copyright
© 2021, Zhang 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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The hepatic AMPK-TET1-SIRT1 axis regulates glucose homeostasis
eLife 10:e70672.
https://doi.org/10.7554/eLife.70672
Further reading
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