Targeting Long Noncoding RNA MALAT1 Preserves Endothelial Cell Integrity and Protects against Kidney Fibrosis

Journal of the American Society of Nephrology, vol. 35

Abstract

Background: Loss of integrity of the peritubular capillary network is directly associated with the development of kidney fibrosis and chronic kidney disease. Here, we aimed to identify long non-coding RNAs (lncRNAs) that could serve as a target to maintain vascular integrity and decrease kidney fibrosis. Methods: We induced vascular injury and kidney fibrosis by ischemia-reperfusion injury (IRI) and unilateral ureteral obstruction (UUO) in VE-cadherin-ERT2;tdTomato mice to label and trace endothelial cells (ECs). Subsequently, we sorted Tomato-positive ECs by FACS and profiled for differentially expressed lncRNAs. We reprocessed transcriptomic datasets to assess kidney and circulating MALAT1 levels in patients with kidney fibrosis. Results: In IRI and UUO, we found 417 and 587 lncRNAs differentially expressed (>2-fold, p<0.05) in the VE-cadherin-derived tomato-positive ECs, respectively. We identified the conserved lncRNA MALAT1 to be increased in ECs in both UUO (7.42-fold) and IRI (2.38 fold). Subsequent gapmer-mediated knockdown of MALAT1 in the UUO model protected against the development of kidney fibrosis, as illustrated by a ~50% decrease in collagen deposition and a concomitant decrease in interstitial α-SMA positive cells. This protective effect was associated with an increase in capillary density and reduced endothelial to mesenchymal transition. Transcriptomic analysis of kidney ECs isolated using FACS from gapmer-MALAT1 treated animals demonstrated that MALAT1 knockdown increased ECM-receptor and cell-cell interaction. Indeed, using the microvessel-on-a-chip platform and transendothelial electric resistance assays, we demonstrated that silencing MALAT1 resulted in increased barrier function, less vascular leakage and a decreased angiogenic response. In addition, MALAT1 knockdown in ECs decreased focal adherens junctions and maintained normal VE-cadherin distribution. Lastly, we found both kidney and circulating MALAT1 levels to be increased in patients with fibrotic kidney disease compared to healthy controls. Conclusion: Taken together, we demonstrated that targeting MALAT1 preserves endothelial cell function and kidney health and may provide novel strategies to counteract the development of fibrosis. Funding: Private Foundation Support

Authors 13

1. Zhao Qiao Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

2. Loïs van der Pluijm Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

3. Daniel Peled

   NYU Langone Health

   Affiliation as printed

   NYU Langone Health, New York, New York, United States

4. Juliette A. de Klerk Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

5. Roderick C. Slieker Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

6. Leen M. ‘t Hart Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

7. Wendy Stam Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

8. Jacques M.G.J. Duijs Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

9. Angela Koudijs Aachen

   Leiden University Medical Center

   Affiliation as printed

   Leids Universitair Medisch Centrum, Leiden, Netherlands;

10. Joris I. Rotmans Aachen

    Leiden University Medical Center

    Affiliation as printed

    Leids Universitair Medisch Centrum, Leiden, Netherlands;

11. Anton Jan van Zonneveld Aachen

    Leiden University Medical Center

    Affiliation as printed

    Leids Universitair Medisch Centrum, Leiden, Netherlands;

12. Coen V Solingen

    NYU Langone Health

    Affiliation as printed

    NYU Langone Health, New York, New York, United States

13. Roel Bijkerk Aachen

    Leiden University Medical Center

    Affiliation as printed

    Leids Universitair Medisch Centrum, Leiden, Netherlands;