Abstract
Significance StatementIschemia-reperfusion AKI (IR-AKI) is common and causes significant morbidity. Effective treatments are lacking. However, preclinical studies suggest that inhibition of angiopoietin-Tie2 vascular signaling promotes injury, whereas activation of Tie2 is protective. We show that kidney ischemia leads to increased levels of the endothelial-specific phosphatase vascular endothelial protein tyrosine phosphatase (VE-PTP; PTPRB), which inactivates Tie2. Activation of Tie2 through VE-PTP deletion, or delivery of a novel angiopoietin mimetic (Hepta-ANG1), abrogated IR-AKI in mice. Single-cell RNAseq analysis showed Tie2 activation promotes increased Entpd1 expression, downregulation of FOXO1 target genes in the kidney vasculature, and emergence of a new subpopulation of glomerular endothelial cells. Our data provide a molecular basis and identify a candidate therapeutic to improve endothelial integrity and kidney function after IR-AKI.BackgroundIschemia-reperfusion AKI (IR-AKI) is estimated to affect 2%-7% of all hospitalized patients. The significant morbidity and mortality associated with AKI indicates urgent need for effective treatments. Previous studies have shown activation of the vascular angiopoietin-Tie2 tyrosine kinase signaling pathway abrogates ischemia-reperfusion injury (IRI). We extended previous studies to (1) determine the molecular mechanism(s) underlying kidney injury and protection related to decreased or increased activation of Tie2, respectively, and (2) to test the hypothesis that deletion of the Tie2 inhibitory phosphatase vascular endothelial protein tyrosine phosphatase (VE-PTP) or injection of a new angiopoietin mimetic protects the kidney from IRI by common molecular mechanism(s).MethodsBilateral IR-AKI was performed in VE-PTP wild-Type or knockout mice and in C57BL/6J mice treated with Hepta-ANG1 or vehicle. Histologic, immunostaining, and single-cell RNA sequencing analyses were performed.ResultsThe phosphatase VE-PTP, which negatively regulates the angiopoietin-Tie2 pathway, was upregulated in kidney endothelial cells after IRI, and genetic deletion of VE-PTP in mice protected the kidney from IR-AKI. Injection of Hepta-ANG1 potently activated Tie2 and protected the mouse kidney from IRI. Single-cell RNAseq analysis of kidneys from Hepta-ANG1-Treated and vehicle-Treated mice identified endothelial-specific gene signatures and emergence of a new glomerular endothelial subpopulation associated with improved kidney function. Overlap was found between endothelial-specific genes upregulated by Hepta-ANG1 treatment and those downregulated in HUVECs with constitutive FOXO1 activation, including Entpd1/ENTPD1 that modulates purinergic receptor signaling.ConclusionsOur data support a key role of the endothelium in the development of IR-AKI, introduce Hepta-ANG1 as a putative new therapeutic biologic, and report a model to explain how IRI reduces Tie2 signaling and how Tie2 activation protects the kidney.PodcastThis article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2023_05_23_JSN_Ang_EP23_052323.mp3.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 969-987 |
| Number of pages | 19 |
| Journal | Journal of the American Society of Nephrology |
| Volume | 34 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 1 2023 |
Funding
H. Maekawa reports research funding: Japan Society for the Promotion of Science and Takeda Science Foundation. M.J. Ansari reports research funding: AlloVir, Eurofins/Transplant Genomics, and Verici Dx and patents or royalties: Tract Therapeutics. K. Boubes reports patents or royalties: pending patent applications for a dialysis catheter and a dialysis needle but has not received any royalties. Y. Alia reports employer: Duly health and care and ownership interest: Duly health and care. B.R. Thomson reports research funding: Bayer. J. Jin has applied for a patent of the ANGPT1 mimetic compound described in the article, and he is a scientific advisor for Mannin Research and QBioMed. J. Jin also reports consultancy: QBioMed, Inc., Mannin Research Inc., Enlighten Biotechnology, Inc., and Alebund Pharmaceutical Inc.; ownership interest: Accubit, Inc.; and advisory or leadership role: Scientific Reports. S.E. Quaggin is listed as an inventor on patents related to therapeutic targeting of the ANGPT-TEK pathway in ocular hypertension and glaucoma and AKI and owns stock in Mannin Research. S.E. Quaggin also receives consulting fees from AstraZeneca, Janssen, the Lowy Medical Research Foundation, Roche/Genentech, Pfizer, Unity, Novartis, Merck, and J&J. S.E. Quaggin also reports honoraria: UIC; patents or royalties: Mannin Research Inc.; advisory or leadership role: AstraZeneca, Genentech/Roche, JCI, Karolinska CVRM Institute, Lowy Medical Research Institute, Mannin, Novartis, Pfizer Aspire program committee, Pfizer, and UNITY; and other interests or relationships: co-founder of Mannin Research. We thank Phoebe Leeaw, Dilip Deb, and Brianna Jenkins for technical and animal husbandry assistance. We thank Ryan Embry and Matthew Schipma for assistance with bioinformatic analysis. Microsurgery and bilateral IRI model in VE-PTPiKO mice was performed at UAB-UCSD O'Brien Core Center for Acute Kidney Injury Research. Bilateral IRI model in C57BL/6J mice was performed in the Microsrugery Core at Northwestern University. Imaging was performed at the Northwestern University Center for Advanced Microscopy and supported by National Cancer Institute CCSG P30 CA060553 awarded to the Robert H. Lurie Comprehensive Cancer Center. Measurement of serum creatinine concentration was performed by John Moore and Yang Yan at the University of Alabama at Birmingham. We thank Michael Ryczko, Mannin Research Inc., who provided unpurified Hepta-ANG1 recombinant fusion protein. We acknowledge support from the UAB-UCSD O'Brien Core Center for Acute Kidney Injury Research (NIH P30-DK079337) for this project. This work was made possible through core services and support from the Northwestern University George M. O'Brien Kidney Research Core Center (NU GoKidney), an NIH/NIDDK funded program (P30 DK114857 to S.E. Quaggin and NEI R01 EY025799 to S.E. Quaggin). This work was supported by the Northwestern University NUSeq Core Facility. Histology services were provided by the Northwestern University Research Histology and Phenotyping Laboratory which is supported by NCI P30-CA060553 awarded to the Robert H Lurie Comprehensive Cancer Center. ACKNOWLEDGMENTS
Keywords
- angiopoietins
- endothelial cells
- endothelium
- ischemia-reperfusion
- ischemic renal failure
- signal transduction
- transcriptional profiling
ASJC Scopus subject areas
- General Medicine