MiR‐23a‐3p alleviates cigarette smoke extract‐induced pulmonary vascular endothelial cell apoptosis by targeting DNAJB1 in emphysema

Abstract

AbstractBackgroundCigarette smoke (CS) is an important risk factor for chronic obstructive pulmonary disease, including emphysema. MicroRNAs (miRNAs) are important regulators of emphysema progression. However, miR‐23a‐3p role in emphysema is unclear.MethodsCS exposure was used to construct emphysema mice models, and cigarette smoke extract (CSE)‐induced pulmonary vascular endothelial cells (PMVECs) were used to mimic emphysema cell models. Mouse lung tissue was stained by immunohistochemical staining, hematoxylin and eosin staining, and TUNEL staining. MiR‐23a‐3p and DnaJ homolog subfamily B member 1 (DNAJB1) levels were tested using quantitative real‐time PCR. DNAJB1 and apoptosis‐related markers' protein levels were examined via western blot analysis. Cell viability and apoptosis were analyzed by MTT assay and flow cytometry. The interaction between miR‐23a‐3p and DNAJB1 was evaluated by dual‐luciferase reporter assay and RIP assay.ResultsMiR‐23a‐3p was downregulated, and DNAJB1 was upregulated in CS‐induced emphysema mice models and CSE‐induced PMVECs. MiR‐23a‐3p overexpression promoted viability and repressed apoptosis in CSE‐induced PMVECs. MiR‐23a‐3p targeted DNAJB1 and negatively regulated DNAJB1 expression. Moreover, DNAJB1 knockdown repressed CSE‐induced PMVECs apoptosis, and miR‐23a‐3p inhibitor reversed this effect. Additionally, miR‐23a‐3p alleviated lung tissue injury and improved emphysema in mice by reducing DNAJB1 expression.ConclusionMiR‐23a‐3p alleviated emphysema progression, which could inhibit CSE‐induced PMVECs apoptosis by targeting DNAJB1.