Boosting ATM activity alleviates ageing and extends lifespan in a mouse model of progeria
Abstract
DNA damage accumulates with age (Lombard et al., 2005). However, whether and how robust DNA repair machinery promotes longevity is elusive. Here, we demonstrate that ATM-centered DNA damage response (DDR) progressively declines with senescence and age, while low dose of chloroquine (CQ) activates ATM, promotes DNA damage clearance, rescues age-related metabolic shift, and prolongs replicative lifespan. Molecularly, ATM phosphorylates SIRT6 deacetylase and thus prevents MDM2-mediated ubiquitination and proteasomal degradation. Extra copies of Sirt6 extend lifespan in Atm-/- mice, with restored metabolic homeostasis. Moreover, the treatment with CQ remarkably extends lifespan of Caenorhabditis elegans, but not the ATM-1 mutants. In a progeria mouse model with low DNA repair capacity, long-term administration of CQ ameliorates premature ageing features and extends lifespan. Thus, our data highlights a pro-longevity role of ATM, for the first time establishing direct causal links between robust DNA repair machinery and longevity, and providing therapeutic strategy for progeria and age-related metabolic diseases.
Data availability
Sequencing data have been deposited in GEO under accession code GSE109280
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Boosting ATM Activity Promotes Longevity in Nematodes and MicePublicly available at the NCBI Gene Expression Omnibus (accession no: GSE109280).
Article and author information
Author details
Funding
National Natural Science Foundation of China (81422016)
- Baohua Liu
Ministry of Science and Technology of the People's Republic of China (2017YFA0503900)
- Baohua Liu
National Natural Science Foundation of China (81501206)
- Minxian Qian
Natural Science Foundation of Guangdong Province (2014A030308011)
- Baohua Liu
Natural Science Foundation of Guangdong Province (2015A030308007)
- Baoming Qin
Shenzhen Science and Technology Innovation Commission (CXZZ20140903103747568)
- Baohua Liu
National Natural Science Foundation of China (91439133)
- Baohua Liu
National Natural Science Foundation of China (81571374)
- Baohua Liu
Ministry of Science and Technology of the People's Republic of China (2016YFC0904600)
- Baohua Liu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Mice were housed and handled in the laboratory animal research center of Shenzhen University. All experiments were performed in accordance with the guidelines of the Institutional Animal Care and Use Committee (IACUC). The protocols were approved by the Animal Welfare and Research Ethics Committee of Shenzhen University (Approval ID: 201412023).
Copyright
© 2018, Qian 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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