Abstract 15078: Long-Non-Coding RNA HypERrlnc Regulates Human Pericyte Function by Modulation of the Endoplasmic Reticulum-Stress Cell Response
Introduction: Pericytes are perivascular mural cells that induce vessel maturation and endothelial barrier function. Long non-coding RNAs (lncRNAs) are known to influence endothelial cell function, but their role in pericyte biology remains unexplored. Endoplasmic reticulum (ER) stress is a common cellular response upon stimuli such as hypoxia that triggers cell death and consecutive organ dysfunction. Here we show that lncRNA HypeERlnc (Hypoxia-Induced Endoplasmic Reticulum-Stress Regulating RNA) affects pericyte function by modulating the ER-stress cell response.
Methods and Results: RNA seq identified 30 hypoxia regulated lncRNAs in primary human pericytes (hPC), including HypERrlnc. Silencing HypERrlnc, which is enriched in the nucleus (nucleus/cytosol ratio: 1.55±0.09, n=3), with LNA-GapmeRs decreased cell viability (MTT assay: 0.77±0.02 vs Ctrl, P<0.001, n=3) and proliferation (Ki67 index 0.85±0.03 vs ctrl, P<0.01, n=3) and downregulated pericyte markers (PDGFRß 0.72±0.07, Desmin 0.22±0.06, P<0.05, vs ctrl, n=8). Loss of HypERrlnc increased permeability of cocultures of hPC and human coronary microvascular endothelial cells (HCMEC) (1.33±0.15 vs Ctrl, P<0.05, n=5) and reduced hPC recruitment towards HCMEC in matrigel assays (recruited hPC 0.75±0.04 vs ctrl, P<0.001, n=4). Transcription factor (TF) activity profiling demonstrated that the ER stress related TF ATF6 was most prominently activated (1.65±0.13 vs ctrl, p<0,001, n=6) upon HypERrlnc knockdown. Immunoblotting for the ER-stress markers cleaved ATF6 (fold change: 1.51±0.1 vs ctrl, P<0.01, n=3), IR1alpha (fold change: 1.6±0.12 vs ctrl, P<0.001, n=3) and soluble BiP (fold change: 0.63±0.03 vs ctrl, P<0.001, n=3) confirmed ER-stress upon HypERlnc loss. Moreover, myocardial HypERrlnc expression in cardiac tissue from patients diagnosed with chronic heart failure (HF) was markedly reduced (0.64±0.13 FC vs ctrl, P<0.05, n=19 HF patients).
Conclusion: LncRNA HypERrlnc regulates the evolution of ER-stress and is important for pericyte survival, proliferation, differentiation, coronary endothelial recruitment and endothelial barrier function. Moreover, downregulation of HypERrlnc in chronic heart failure indicates a role of HypERrlnc in human cardiac disease.
Author Disclosures: F. Bischoff: None. A. Werner: None. J. Boeckel: None. S. Demolli: None. K. Michalik: None. B. Meder: None. H.A. Katus: None. J. Haas: None. W. Chen: None. D. John: None. S. Uchida: None. A.M. Zeiher: None. S. Dimmeler: None. C.M. Zehendner: None.
- © 2016 by American Heart Association, Inc.