Marked TGF-β-regulated miRNA expression changes in both COPD and control lung fibroblasts

Area of Science:

• Pulmonary Medicine
• Molecular Biology
• Genetics

Background:

• Chronic obstructive pulmonary disease (COPD) is characterized by impaired tissue repair mechanisms.
• Transforming growth factor-beta (TGF-β) signaling pathway dysregulation is implicated in COPD pathogenesis.
• MicroRNAs (miRNAs) are key regulators of gene expression and may mediate TGF-β's effects in fibroblasts.

Purpose of the Study:

• To identify TGF-β-regulated miRNAs in lung fibroblasts.
• To compare miRNA regulation and expression in COPD versus control fibroblasts.
• To investigate the functional relevance of identified miRNAs and their targets in COPD.

Main Methods:

• Small RNA sequencing of lung fibroblasts from COPD patients and controls, stimulated with TGF-β.
• Linear regression analysis to identify TGF-β-responsive and COPD-associated miRNAs.
• Interaction analysis to detect differential TGF-β responses between COPD and control fibroblasts.
• Bioinformatic analysis (Ago2-IP data, Enrichr) to predict miRNA targets and functions.

Main Results:

• 46 TGF-β-regulated miRNAs in COPD fibroblasts and 86 in controls were identified (FDR < 0.05).
• MiR-27a-5p was the most significantly upregulated miRNA.
• MiR-148b-3p, miR-589-5p, and miR-376b-3p showed differential TGF-β responses in COPD (FDR < 0.25).
• MiR-660-5p was significantly upregulated in COPD fibroblasts (FDR < 0.05).
• Predicted targets of key miRNAs were involved in gene transcription regulation.

Conclusions:

• Altered TGF-β-induced miRNA regulation in COPD fibroblasts contributes to aberrant tissue repair.
• Differential expression of miR-660-5p in COPD fibroblasts is a potential mechanism underlying COPD pathology.
• These findings highlight miRNAs as potential therapeutic targets for COPD treatment.