10779/rcsi.10785575.v1
Tidi Hassan
Tidi
Hassan
Tomás P. Carroll
Tomás P.
Carroll
Patrick G. Buckley
Patrick G.
Buckley
Robert Cummins
Robert
Cummins
Shane J. O'Neill
Shane J.
O'Neill
Noel G. McElvaney
Noel G.
McElvaney
Catherine M. Greene
Catherine M.
Greene
miR-199a-5p silencing regulates the unfolded protein response in chronic obstructive pulmonary disease and α1-antitrypsin deficiency.
Royal College of Surgeons in Ireland
2019
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
Medicine
2019-11-22 16:35:29
Journal contribution
https://repository.rcsi.com/articles/journal_contribution/miR-199a-5p_silencing_regulates_the_unfolded_protein_response_in_chronic_obstructive_pulmonary_disease_and_1-antitrypsin_deficiency_/10785575
<p>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.</p>
<p>OBJECTIVES: To investigate miRNA expression and function in MM and ZZ monocytes and identify miRNA(s) regulating the unfolded protein response.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>