The Role of MicroRNA-21 in Venous Neointimal Hyperplasia: Implications for Targeting miR-21 for VNH Treatment
Journal
Molecular Therapy
Journal Volume
27
Journal Issue
9
Pages
1681-1693
Date Issued
2019
Author(s)
Kilari, S., Cai, C., Zhao, C., Sharma, A., Chernogubova, E., Simeon, M., Wu, C.-C., Maegdefessel, L., Misra, S.
Abstract
The molecular mechanism of hemodialysis access arteriovenous fistula (AVF) failure due to venous neointimal hyperplasia (VNH) is not known. The role of microRNA-21 (miR-21) in VNH associated with AVF failure was investigated by performing in vivo and in vitro experiments. In situ hybridization results revealed that miR-21 expression increased and was associated with fibroblasts in failed AVFs from patients. In a murine AVF model, qRT-PCR gene expression results showed a significant increase in miR-21 and a decrease in miR-21 target genes in graft veins (GVs) compared to contralateral veins in mouse AVF. miR-21 knockdown in GVs was performed using a lentivirus-mediated small hairpin RNA (shRNA), and this improved AVF patency with a decrease in neointima compared to control GVs. Moreover, loss of miR-21 in GVs significantly decreased the Tgfβ1, Col-Ia, and Col-Iva genes. Immunohistochemistry demonstrated a significant decrease in myofibroblasts and proliferation with an increase in terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining in miR-21-knockdown vessels, along with a decrease in hypoxia-inducible factor-1 alpha (HIF-1α) and phospho-SMAD2 (pSMAD-2) and phospho-SMAD3 (pSMAD-3) and an increase in phosphatase and tensin homolog (PTEN) staining. Hypoxic fibroblast knockdown for miR-21 showed a significant decrease in Tgfβ-1 expression and pSMAD-2 and -3 levels and a decrease in myofibroblasts. These results indicate that miR-21 upregulation causes VNH formation by fibroblast-to-myofibroblast differentiation. About 50% of hemodialysis arteriovenous fistula (AVF) will fail within a year of placement. Novel strategies that can improve fistula patency are needed. The present study demonstrated a significant role of microRNA-21 in AVF failure, and its knockdown in outflow veins of AVF improved the AVF function and durability. ? 2019 The Authors
Subjects
animal models; arteriovenous fistula; chronic kidney disease; miR-21; TGF-β; vascular remodeling
SDGs
Other Subjects
hypoxia inducible factor 1alpha; microRNA 21; phosphatidylinositol 3,4,5 trisphosphate 3 phosphatase; short hairpin RNA; Smad2 protein; transforming growth factor beta1; biological marker; microRNA; MIRN21 microRNA, human; small interfering RNA; adult; aged; animal cell; animal experiment; animal model; animal tissue; Article; cell differentiation; cell proliferation; clinical article; Col Ia gene; Col Iva gene; controlled study; disease course; drug targeting; female; fibroblast; gene; gene expression; gene function; gene knockdown; human; human tissue; hyperplasia; hypoxic cell; immunohistochemistry; male; middle aged; mouse; myofibroblast; neointima; nonhuman; pathogenesis; protein expression; protein phosphorylation; real time polymerase chain reaction; Tgfbeta1 gene; TUNEL assay; upregulation; vein graft; vein occlusion; venous neointimal hyperplasia; animal; apoptosis; arteriovenous fistula; disease model; fibrosis; genetic transduction; genetics; hyperplasia; hypoxia; Lentivirus; metabolism; neointima; pathology; RNA interference; vein; Animals; Apoptosis; Arteriovenous Fistula; Biomarkers; Cell Differentiation; Cell Proliferation; Disease Models, Animal; Fibroblasts; Fibrosis; Gene Expression; Gene Knockdown Techniques; Humans; Hyperplasia; Hypoxia; Immunohistochemistry; Lentivirus; Male; Mice; MicroRNAs; Myofibroblasts; Neointima; RNA Interference; RNA, Small Interfering; Transduction, Genetic; Veins
Type
journal article