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- Li, Daniel Y., et al.
(författare)
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H19 Induces Abdominal Aortic Aneurysm Development and Progression
- 2018
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Ingår i: Circulation. - : LIPPINCOTT WILLIAMS & WILKINS. - 0009-7322 .- 1524-4539. ; 138:15, s. 1551-1568
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Tidskriftsartikel (refereegranskat)abstract
- Background: Long noncoding RNAs have emerged as critical molecular regulators in various biological processes and diseases. Here we sought to identify and functionally characterize long noncoding RNAs as potential mediators in abdominal aortic aneurysm development. Methods: We profiled RNA transcript expression in 2 murine abdominal aortic aneurysm models, Angiotensin II (ANGII) infusion in apolipoprotein E-deficient (ApoE(-/-)) mice (n=8) and porcine pancreatic elastase instillation in C57BL/6 wild-type mice (n=12). The long noncoding RNA H19 was identified as 1 of the most highly upregulated transcripts in both mouse aneurysm models compared with sham-operated controls. This was confirmed by quantitative reverse transcription-polymerase chain reaction and in situ hybridization. Results: Experimental knock-down of H19, utilizing site-specific antisense oligonucleotides (LNA-GapmeRs) in vivo, significantly limited aneurysm growth in both models. Upregulated H19 correlated with smooth muscle cell (SMC) content and SMC apoptosis in progressing aneurysms. Importantly, a similar pattern could be observed in human abdominal aortic aneurysm tissue samples, and in a novel preclinical LDLR-/- (low-density lipoprotein receptor) Yucatan mini-pig aneurysm model. In vitro knock-down of H19 markedly decreased apoptotic rates of cultured human aortic SMCs, whereas overexpression of H19 had the opposite effect. Notably, H19-dependent apoptosis mechanisms in SMCs appeared to be independent of miR-675, which is embedded in the first exon of the H19 gene. A customized transcription factor array identified hypoxia-inducible factor 1 as the main downstream effector. Increased SMC apoptosis was associated with cytoplasmic interaction between H19 and hypoxia-inducible factor 1 and sequential p53 stabilization. Additionally, H19 induced transcription of hypoxia-inducible factor 1 via recruiting the transcription factor specificity protein 1 to the promoter region. Conclusions: The long noncoding RNA H19 is a novel regulator of SMC survival in abdominal aortic aneurysm development and progression. Inhibition of H19 expression might serve as a novel molecular therapeutic target for aortic aneurysm disease.
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| 2. |
- Eken, Suzanne M
(författare)
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Role and therapeutic potential of non-coding RNAs in vascular remodeling and atherosclerotic plaque formation
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Atherosclerosis and its clinical sequelae remain a world leading cause of disease and death, despite recent advances in primary and secondary prevention. The silently progressive character of the disease, in combination with the influence of individual patient characteristics, makes acute events difficult to predict and prevent. There is a need for (1) noninvasive, accurate diagnostic methods and (2) individually tailored therapies, in order to provide effective treatment whilst avoiding unnecessary interventions and iatrogenic damage. In the search for novel detection methods and drugs, non-coding RNA has emerged as a class of important biological regulators, being crucially involved in virtually every cellular process. We show that patients at risk for cardiovascular events display characteristic non-coding RNA patterns and could be treated with RNA interference (RNAi) therapy, targeting and normalizing previously ‘undruggable’ physiological disruptions. In order to measure up to these high expectations, findings from basic non-coding RNA research need to be applied in (pre-)clinical studies. MicroRNAs (miRNA, miR) have been demonstrated to be modifiers of cardiovascular disease via posttranscriptional inhibition of messenger RNA. In this thesis, in vitro as well as in vivo modulation of clinically relevant miRNAs are presented as a therapeutic approach to alter vascular cell behavior and induce reparative arterial remodeling in three cardiovascular diseases (stroke, abdominal aortic aneurysm (AAA) and radiation-induced vasculopathy). In two different mouse models of AAA, we showed that miR-24 treatment hampers AAA expansion. Cell and human tissue experiments demonstrated a positive effect of miR-24 that could be attributed to an inhibitory action of this miRNA on chitinase 3-like 1, a marker of macrophage-induced inflammation. In AAA, a disease for which screening has been suggested but fails to meet socioeconomic demands, we are the first to present a sufficiently powered biomarker study, where miR-99b, detected in the circulation, could predict aneurysm expansion and rupture risk. In patients with carotid artery atherosclerosis at risk for stroke, miR-210 was decreased in the atherosclerotic fibrous cap. In vivo experiments of murine carotid injury and plaque rupture showed that low expression of miR-210 was associated with fibrous cap smooth muscle cell apoptosis through adenomatous polyposis coli, and that miR-210 treatment could prevent carotid plaque rupture in mice. In chronic arterial inflammation secondary to radiotherapy, miR-29b deregulation demonstrated an adverse inflammatory and fibrotic response, which in mice could be corrected with miR-29b mimic therapy, partly through a restored inhibition of miR-29b targets pentraxin 3 and dipeptidyl-peptidase 4. Our approaches have not only revealed possible diagnostic and therapeutic use of non-coding RNAs, but have also presented us with the difficulties and limitations of presenting exogenous RNA modifiers to a diseased circulatory system. Distribution, efficacy, off-target effects, and pleiotropy are issues that need to be addressed before non-coding RNAi therapy can be exploited clinically.
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