Peer Reviewed

1

Document Type

Article

Publication Date

1-2-2014

Keywords

Adult, Asymptomatic Diseases, Biomarkers, Blotting, Western, Cytokines, Female, Gene Expression Profiling, Gene Silencing, Humans, Male, Methylation, MicroRNAs, Middle Aged, Monocytes, Phenotype, Polymerase Chain Reaction, Pulmonary Disease, Chronic Obstructive, Sequence Analysis, RNA, Stress, Physiological, Unfolded Protein Response, Up-Regulation, alpha 1-Antitrypsin Deficiency

Funder/Sponsor

Science Foundation Ireland

Comments

Originally Published in: Hassan T. Carroll TP, Buckley PG, Cummins R, O’Neill SJ, Mcelvaney NG, Greene CM. miR-199a-5p silencing regulates the unfolded protein response in chronic obstructive pulmonary disease and α1-antitrypsin deficiency. American Journal of Respiratory and Critical Care Medicine. 2014 Feb 1;189(3):263-73 DOI: 10.1164/rccm.201306-1151OC. Copyright © 2015 by the American Thoracic Society. The final publication is available at http://www.atsjournals.org/

Abstract

RATIONALE: Retention of abnormal α1-antitrypsin (AAT) activates the unfolded protein response in AAT-deficient monocytes. The regulatory role of microRNAs (miRNAs) in unfolded protein responses and chronic obstructive pulmonary disease pathogenesis has not been investigated.

OBJECTIVES: To investigate miRNA expression and function in MM and ZZ monocytes and identify miRNA(s) regulating the unfolded protein response.

METHODS: Peripheral blood monocytes were isolated from asymptomatic and symptomatic MM and ZZ individuals for miRNA expression profiling and pyrosequencing analysis. miRNA/gene and protein expression was measured with quantitative polymerase chain reaction and Western blotting. Overexpression and inhibition studies were performed with pre-miR or anti-miR, respectively. Luciferase reporter genes were used to elucidate direct miRNA-target interactions. Inflammatory cytokines were detected using the Meso Scale Discovery Plex assays.

MEASUREMENTS AND MAIN RESULTS: Forty-three miRNAs were differentially expressed, with miR-199a-5p most highly up-regulated in asymptomatic ZZ versus MM monocytes. miR-199a-2 promoter hypermethylation inhibits miR-199a-5p expression and was increased in symptomatic MM and ZZ monocytes compared with asymptomatic counterparts. GRP78, activating transcription factor 6, p50, and p65 were increased in symptomatic versus asymptomatic ZZ monocytes. Reciprocal down- or up-regulation of these markers was observed after miRNA modulation. Direct miR-199a-5p targeting of activating transcription factor 6, p50, and p65 by miR-199a-5p was demonstrated using luciferase reporter systems. Overexpression of miR-199a-5p also decreased other arms of the UPR and expression of cytokines that are not putative targets.

CONCLUSIONS: miR-199a-5p is a key regulator of the unfolded protein response in AAT-deficient monocytes, and epigenetic silencing of its expression regulates this process in chronic obstructive pulmonary disease.

Disciplines

Medicine and Health Sciences

Citation

Hassan T, Carroll TP, Buckley PG, Cummins R, O'Neill SJ, McElvaney NG, Greene CM. miR-199a-5p silencing regulates the unfolded protein response in chronic obstructive pulmonary disease and α1-antitrypsin deficiency. American Journal of Respiratory and Critical Care Medicine. 2014;189(3):263-73.

PubMed ID

24299514

DOI Link

10.1164/rccm.201306-1151OC

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 License.

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