Mechanical stress induces pre-B-cell colony-enhancing factor/NAMPT expression via epigenetic regulation by miR-374a and miR-568 in human lung endothelium.
Increased lung vascular permeability and alveolar edema are cardinal features of inflammatory conditions such as acute respiratory distress syndrome (ARDS) and ventilator-induced lung injury (VILI). We previously demonstrated that pre-B-cell colony-enhancing factor (PBEF)/NAMPT, the proinflammatory cytokine encoded by NAMPT, participates in ARDS and VILI inflammatory syndromes. The present study evaluated posttranscriptional regulation of PBEF/NAMPT gene expression in human lung endothelium via 3'-untranslated region (UTR) microRNA (miRNA) binding. In silico analysis identified hsa-miR-374a and hsa-miR-568 as potential miRNA candidates. Increased PBEF/NAMPT transcription (by RT-PCR) and expression (by Western blotting) induced by 18% cyclic stretch (CS) (2 h: 3.4 ± 0.06 mRNA fold increase (FI); 10 h: 1.5 ± 0.06 protein FI) and by LPS (4 h: 3.8 ± 0.2 mRNA FI; 48 h: 2.6 ± 0.2 protein FI) were significantly attenuated by transfection with mimics of hsa-miR-374a or hsa-miR-568 (40-60% reductions each). LPS and 18% CS increased the activity of a PBEF/NAMPT 3'-UTR luciferase reporter (2.4-3.25 FI) with induction reduced by mimics of each miRNA (44-60% reduction). Specific miRNA inhibitors (antagomirs) for each PBEF/NAMPT miRNA significantly increased the endogenous PBEF/NAMPT mRNA (1.4-3.4 ± 0.1 FI) and protein levels (1.2-1.4 ± 0.1 FI) and 3'-UTR luciferase activity (1.4-1.7 ± 0.1 FI) compared with negative antagomir controls. Collectively, these data demonstrate that increased PBEF/NAMPT expression induced by bioactive agonists (i.e., excessive mechanical stress, LPS) involves epigenetic regulation with hsa-miR-374a and hsa-miR-568, representing novel therapeutic strategies to reduce inflammatory lung injury.
Institute for Personalized Respiratory Medicine, Department of Medicine, Section of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois at Chicago, Chicago, Illinois.
Djanybek M
DM
Adyshev
Venkateswaran Ramamoorthi
VR
Elangovan
Nurgul
N
Moldobaeva
Brandon
B
Mapes
Xiaoguang
X
Sun
Joe G N
JG
Garcia
D016207:Cytokines / Q000378:metabolism*; D004727:Endothelium / Q000378:metabolism*; D044127:Epigenesis, Genetic; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007249:Inflammation / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D008168:Lung / Q000378:metabolism*; D035683:MicroRNAs / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D054409:Nicotinamide Phosphoribosyltransferase / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D012128:Respiratory Distress Syndrome / Q000235:genetics; D013314:Stress, Mechanical; D055397:Ventilator-Induced Lung Injury / Q000235:genetics* / Q000378:metabolism
D016207:Cytokines; D008070:Lipopolysaccharides; C587995:MIRN374 microRNA 374, human; C587996:MIRN568 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D054409:Nicotinamide Phosphoribosyltransferase; C085455:nicotinamide phosphoribosyltransferase, human