Empagliflozin reduces podocyte lipotoxicity in experimental Alport syndrome

  1. Mengyuan Ge
  2. Judith Molina
  3. Jin Ju Kim
  4. Shamroop Kumar Mallela
  5. Anis Ahmad
  6. Javier Varona Santos
  7. Hassan Al-Ali
  8. Alla Mitrofanova
  9. Kumar Sharma
  10. Flavia Fontanesi
  11. Sandra Merscher
  12. Alessia Fornoni  Is a corresponding author
  1. University of Miami, United States
  2. The University of Texas Health Science Center at San Antonio, United States

Abstract

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are anti-hyperglycemic agents that prevent glucose reabsorption in proximal tubular cells. SGLT2i improves renal outcomes in both diabetic and non-diabetic patients, indicating it may have beneficial effects beyond glycemic control. Here, we demonstrate that SGLT2i affects energy metabolism and podocyte lipotoxicity in experimental Alport syndrome (AS). In vitro, we found that SGLT2 protein was expressed in human and mouse podocytes to a similar extent of tubular cells. Newly established immortalized podocytes from Col4a3 knockout mice (AS podocytes) accumulate lipid droplets along with increased apoptosis when compared to wildtype podocytes. Treatment with SGLT2i empagliflozin reduces lipid droplet accumulation and apoptosis in AS podocytes. Empagliflozin inhibits the utilization of glucose/pyruvate as a metabolic substrate in AS podocytes but not in AS tubular cells. In vivo, we demonstrate that empagliflozin reduces albuminuria and prolongs the survival of AS mice. Empagliflozin-treated AS mice show decreased serum blood urea nitrogen and creatinine levels in association with reduced triglyceride and cholesterol ester content in kidney cortices when compared to AS mice. Lipid accumulation in kidney cortices correlates with the decline in renal function. In summary, empagliflozin reduces podocyte lipotoxicity and improves kidney function in experimental AS in association with the energy substrates switch from glucose to fatty acids in podocytes.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file.

Article and author information

Author details

  1. Mengyuan Ge

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  2. Judith Molina

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  3. Jin Ju Kim

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  4. Shamroop Kumar Mallela

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  5. Anis Ahmad

    Department of Radiation Oncology, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  6. Javier Varona Santos

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  7. Hassan Al-Ali

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  8. Alla Mitrofanova

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  9. Kumar Sharma

    Center for Precision Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, United States
    Competing interests
    Kumar Sharma, is founder of SygnaMap..
  10. Flavia Fontanesi

    Department of Biochemistry and Molecular Biology, University of Miami, Miami, United States
    Competing interests
    No competing interests declared.
  11. Sandra Merscher

    Department of Medicine, University of Miami, Miami, United States
    Competing interests
    Sandra Merscher, is an inventor on pending (PCT/US2019/032215; US 17/057,247; PCT/US2019/041730; PCT/US2013/036484; US 17/259,883; US17/259,883; JP501309/2021, EU19834217.2; CN-201980060078.3; CA2,930,119; CA3,012,773,CA2,852,904) or issued patents (US10,183,038 and US10,052,345) aimed at preventing and treating renal disease. They stand to gain royalties from their future commercialization. SM holds indirect equity interest in, and potential royalty from, ZyVersa Therapeutics, Inc. by virtue of assignment and licensure of a patent estate. SM is supported by Aurinia Pharmaceuticals Inc..
  12. Alessia Fornoni

    Department of Biochemistry and Molecular Biology, University of Miami, Miami, United States
    For correspondence
    AFornoni@med.miami.edu
    Competing interests
    Alessia Fornoni, is an inventor on pending (PCT/US2019/032215; US 17/057,247; PCT/US2019/041730; PCT/US2013/036484; US 17/259,883; US17/259,883; JP501309/2021, EU19834217.2; CN-201980060078.3; CA2,930,119; CA3,012,773,CA2,852,904) or issued patents (US10,183,038 and US10,052,345) aimed at preventing and treating renal disease. They stand to gain royalties from their future commercialization. AF is Vice-President of L&F Health LLC and is a consultant for ZyVersa Therapeutics, Inc. ZyVersa Therapeutics, Inc has licensed worldwide rights to develop and commercialize hydroxypropyl-beta-cyclodextrin from L&F Research for the treatment of kidney disease. AF also holds equities in Renal 3 River Corporation. AF and SM are supported by Aurinia Pharmaceuticals Inc..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1313-7773

Funding

National Institutes of Health (R01DK117599,R01DK104753,R01CA227493)

  • Sandra Merscher
  • Alessia Fornoni

Miami Clinical and Translational Science Institute, University of Miami (U54DK083912,UM1DK100846,U01DK116101,UL1TR000460)

  • Alessia Fornoni

Army Research Office (W911NF-21-1-0359)

  • Flavia Fontanesi

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Ilse S Daehn, Icahn School of Medicine at Mount Sinai, United States

Ethics

Animal experimentation: All studies involving mice were approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Miami. The University of Miami (UM) has an Animal Welfare Assurance on file with the Office of Laboratory Animal Welfare, NIH (A-3224-01, effective November 24, 2015). Additionally, UM is registered with the US Department of Agriculture Animal and Plant Health Inspection Service, effective December 2014, registration 58-R-007. As of October 22, 2013, the Council on Accreditation of the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC International) has continued UM's full accreditation.

Version history

  1. Received: September 8, 2022
  2. Preprint posted: October 4, 2022 (view preprint)
  3. Accepted: April 26, 2023
  4. Accepted Manuscript published: May 2, 2023 (version 1)
  5. Version of Record published: May 15, 2023 (version 2)

Copyright

© 2023, Ge 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.

Metrics

  • 1,151
    Page views
  • 271
    Downloads
  • 9
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Mengyuan Ge
  2. Judith Molina
  3. Jin Ju Kim
  4. Shamroop Kumar Mallela
  5. Anis Ahmad
  6. Javier Varona Santos
  7. Hassan Al-Ali
  8. Alla Mitrofanova
  9. Kumar Sharma
  10. Flavia Fontanesi
  11. Sandra Merscher
  12. Alessia Fornoni
(2023)
Empagliflozin reduces podocyte lipotoxicity in experimental Alport syndrome
eLife 12:e83353.
https://doi.org/10.7554/eLife.83353

Share this article

https://doi.org/10.7554/eLife.83353

Further reading

    1. Cell Biology
    Kazuki Hanaoka, Kensuke Nishikawa ... Kouichi Funato
    Research Article

    Membrane contact sites (MCSs) are junctures that perform important roles including coordinating lipid metabolism. Previous studies have indicated that vacuolar fission/fusion processes are coupled with modifications in the membrane lipid composition. However, it has been still unclear whether MCS-mediated lipid metabolism controls the vacuolar morphology. Here, we report that deletion of tricalbins (Tcb1, Tcb2, and Tcb3), tethering proteins at endoplasmic reticulum (ER)–plasma membrane (PM) and ER–Golgi contact sites, alters fusion/fission dynamics and causes vacuolar fragmentation in the yeast Saccharomyces cerevisiae. In addition, we show that the sphingolipid precursor phytosphingosine (PHS) accumulates in tricalbin-deleted cells, triggering the vacuolar division. Detachment of the nucleus–vacuole junction (NVJ), an important contact site between the vacuole and the perinuclear ER, restored vacuolar morphology in both cells subjected to high exogenous PHS and Tcb3-deleted cells, supporting that PHS transport across the NVJ induces vacuole division. Thus, our results suggest that vacuolar morphology is maintained by MCSs through the metabolism of sphingolipids.

    1. Cell Biology
    2. Chromosomes and Gene Expression
    Monica Salinas-Pena, Elena Rebollo, Albert Jordan
    Research Article

    Histone H1 participates in chromatin condensation and regulates nuclear processes. Human somatic cells may contain up to seven histone H1 variants, although their functional heterogeneity is not fully understood. Here, we have profiled the differential nuclear distribution of the somatic H1 repertoire in human cells through imaging techniques including super-resolution microscopy. H1 variants exhibit characteristic distribution patterns in both interphase and mitosis. H1.2, H1.3, and H1.5 are universally enriched at the nuclear periphery in all cell lines analyzed and co-localize with compacted DNA. H1.0 shows a less pronounced peripheral localization, with apparent variability among different cell lines. On the other hand, H1.4 and H1X are distributed throughout the nucleus, being H1X universally enriched in high-GC regions and abundant in the nucleoli. Interestingly, H1.4 and H1.0 show a more peripheral distribution in cell lines lacking H1.3 and H1.5. The differential distribution patterns of H1 suggest specific functionalities in organizing lamina-associated domains or nucleolar activity, which is further supported by a distinct response of H1X or phosphorylated H1.4 to the inhibition of ribosomal DNA transcription. Moreover, H1 variants depletion affects chromatin structure in a variant-specific manner. Concretely, H1.2 knock-down, either alone or combined, triggers a global chromatin decompaction. Overall, imaging has allowed us to distinguish H1 variants distribution beyond the segregation in two groups denoted by previous ChIP-Seq determinations. Our results support H1 variants heterogeneity and suggest that variant-specific functionality can be shared between different cell types.