Ferroptotic stress promotes the accumulation of pro-inflammatory proximal tubular cells in maladaptive renal repair
- Duke University School of Medicine, United States
- Duke University, United States
- University of North Carolina at Chapel Hill, United States
Abstract
Overwhelming lipid peroxidation induces ferroptotic stress and ferroptosis, a non-apoptotic form of regulated cell death that has been implicated in maladaptive renal repair in mice and humans. Using single-cell transcriptomic and mouse genetic approaches, we show that proximal tubular (PT) cells develop a molecularly distinct, pro-inflammatory state following injury. While these inflammatory PT cells transiently appear after mild injury and return to their original state without inducing fibrosis, after severe injury they accumulate and contribute to persistent inflammation. This transient inflammatory PT state significantly downregulates glutathione metabolism genes, making the cells vulnerable to ferroptotic stress. Genetic induction of high ferroptotic stress in these cells after mild injury leads to the accumulation of the inflammatory PT cells, enhancing inflammation and fibrosis. Our study broadens the roles of ferroptotic stress from being a trigger of regulated cell death to include the promotion and accumulation of proinflammatory cells that underlie maladaptive repair.
Data availability
Sequencing data have been deposited in GEO under accession codes GSE161201. Primer sequence information is available in the supplementary file.
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The use of cold active proteases can dramatically reduce single cell RNA-seq gene expression artifactsNCBI Gene Expression Omnibus, GSE94333.
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The Single Cell Transcriptomic Landscape of Early Human Diabetic NephropathyNCBI Gene Expression Omnibus, GSE131882.
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Single Cell Transcriptional Analysis of Donor and Recipient Immune Cell Chimerism in the Rejecting Kidney TransplantNCBI Gene Expression Omnibus, GSE145927.
Article and author information
Author details
Purushothama Rao Tata
Funding
National Institute of Diabetes and Digestive and Kidney Diseases (R01 DK123097)
- Tomokazu Souma
National Institute of Diabetes and Digestive and Kidney Diseases (P30 DK114857)
- Tomokazu Souma
American Society of Nephrology
- Tomokazu Souma
American Heart Association
- Shintaro Ide
Astellas Foundation for Research on Metabolic Disorders
- Kana Ide
Japan Society for the Promotion of Science
- Yoshihiko Kobayashi
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 Institutional Animal Care and Use Committee at Duke University and performed according to the IACUC-approved protocol (A051-18-02 and A014-21-01) and adhered to the NIH Guide for the Care and Use of Laboratory.
Copyright
© 2021, Ide 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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Ferroptotic stress promotes the accumulation of pro-inflammatory proximal tubular cells in maladaptive renal repair
eLife 10:e68603.
https://doi.org/10.7554/eLife.68603
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