Anti–microRNA-21 oligonucleotides prevent Alport nephropathy progression by stimulating metabolic pathways
Ivan G. Gomez, … , B. Nelson Chau, Jeremy S. Duffield
Ivan G. Gomez, … , B. Nelson Chau, Jeremy S. Duffield
Published November 21, 2014
Citation Information: J Clin Invest. 2015;125(1):141-156. https://doi.org/10.1172/JCI75852.
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Research Article Nephrology

Anti–microRNA-21 oligonucleotides prevent Alport nephropathy progression by stimulating metabolic pathways

Abstract

MicroRNA-21 (miR-21) contributes to the pathogenesis of fibrogenic diseases in multiple organs, including the kidneys, potentially by silencing metabolic pathways that are critical for cellular ATP generation, ROS production, and inflammatory signaling. Here, we developed highly specific oligonucleotides that distribute to the kidney and inhibit miR-21 function when administered subcutaneously and evaluated the therapeutic potential of these anti–miR-21 oligonucleotides in chronic kidney disease. In a murine model of Alport nephropathy, miR-21 silencing did not produce any adverse effects and resulted in substantially milder kidney disease, with minimal albuminuria and dysfunction, compared with vehicle-treated mice. miR-21 silencing dramatically improved survival of Alport mice and reduced histological end points, including glomerulosclerosis, interstitial fibrosis, tubular injury, and inflammation. Anti–miR-21 enhanced PPARα/retinoid X receptor (PPARα/RXR) activity and downstream signaling pathways in glomerular, tubular, and interstitial cells. Moreover, miR-21 silencing enhanced mitochondrial function, which reduced mitochondrial ROS production and thus preserved tubular functions. Inhibition of miR-21 was protective against TGF-β–induced fibrogenesis and inflammation in glomerular and interstitial cells, likely as the result of enhanced PPARα/RXR activity and improved mitochondrial function. Together, these results demonstrate that inhibition of miR-21 represents a potential therapeutic strategy for chronic kidney diseases including Alport nephropathy.

Authors

Ivan G. Gomez, Deidre A. MacKenna, Bryce G. Johnson, Vivek Kaimal, Allie M. Roach, Shuyu Ren, Naoki Nakagawa, Cuiyan Xin, Rick Newitt, Shweta Pandya, Tai-He Xia, Xueqing Liu, Dorin-Bogdan Borza, Monica Grafals, Stuart J. Shankland, Jonathan Himmelfarb, Didier Portilla, Shiguang Liu, B. Nelson Chau, Jeremy S. Duffield

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Figure 5

Global transcriptome sequencing of kidneys from Col4a3–/– mice provides unbiased insight into Alport nephropathy and the actions of anti–miR-21.

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Global transcriptome sequencing of kidneys from Col4a3–/– mice provides ...
(A) Pathways analysis of Col4a3+/+ compared with Col4a3–/– kidneys at 9 weeks showing the most significantly regulated gene ontology pathways, where red denotes upregulated and blue denotes downregulated genes. Height of the bar reflects statistical enrichment (–log10 P value) for the pathways, while x axis reflects the total number of regulated genes in each pathway. (B) Pathways analysis of Col4a3–/– kidneys at 9 weeks treated with vehicle compared with 5.5 weeks of anti–miR-21 treatment, where red denotes upregulated and blue downregulated genes. Note that mitochondrial function genes are derepressed and PPARα signaling is derepressed as identified in 2 pathways (LPS/IL-1 inhibition of RXR function and PPARα/RXRα function) (arrows). (C–F) Western blots at 9 weeks demonstrating the effect of disease and anti–miR-21 on whole kidney levels of PPARα, MCAD, ACAT1, and peroxisomal PMP-70. Normalized densitometry is shown (AU). (D and E) Blots were obtained from the same experiment. Actin blots were derived from parallel samples run on a separate gel, and lines indicate splicing of blots). (G) Schematic showing the effect of disease (no. 1) and anti–miR-21 treatment (no. 2) on PPARα/RXRα-regulated pathways in the nucleus (blue), peroxisome (brown), and mitochondrion (pink) at week 9. PPARα and PGC1α as transcriptionally regulated genes as well as transcription factors are shown regulating downstream genes by green connectors. PPARα target and interactor genes are significantly (*) enhanced (red thermometers) by anti–miR-21 treatment including FABP, ACAA1, CPT, ACADL, whereas PPARα-mediated transcriptional suppression of cJUN is also observed. Analysis performed using Bioconductor LIMMA program. n = 3/group.