COPD patients' bronchoalveolar lavage fluid-derived exosomes inhibit osteoblast differentiation via miR-223-3p/FOXO3 pathway

Abstract

Objective To explore the role and mechanism of the exosomes derived from bronchoalveolar lavage fluid (BALF) of patients with chronic obstructive pulmonary disease (COPD-Exo) in regulating osteoblast differentiation. Methods A total of 6 COPD patients and 6 non-COPD patients admitted in our hospital in June 2023 were recruited, and their BALF samples were collected during the process. COPD-Exo and exosomes from the non-COPD patients (Ctrl-Exo) were extracted and identified by electron microscopy and Western blotting. Alizarin red staining and qRT-PCR were used to detect the differences in osteoblast differentiation after COPD-Exo and Ctrl-Exo intervention. Bioinformatics analysis was performed on the microRNA (miRNA) expression profiles of COPD-Exo and Ctrl-Exo in the GEO database (GSE218571) to obtain differentially expressed miRNAs. Antagomir was used to block mircoRNA function, and the miRNAs with osteogenic differentiation regulatory function were identified. Targetscan software was used to predict the downstream target genes of the miRNAs, and then these miRNAs were verified. Results Exo could be extracted from BALF of both COPD and non-COPD patients. Alizarin red staining and qRT-PCR results showed that COPD-Exo inhibited the osteogenic differentiation of human hFOB 1.19 osteoblasts (P < 0.05). Bioinformatics analysis indicated that the expression level of miR-223-3p was significantly up-regulated in COPD-Exo. Blocking miR-223-3p with Antagomir could alleviate the osteogenic differentiation of human hFOB 1.19 osteoblasts inhibited by COPD-Exo (P < 0.05). Targetscan prediction revealed that miR-223-3p may target and inhibit the expression of osteogenic differentiation-related factor FOXO3 (P < 0.05). Conclusion COPD-Exo can inhibit the osteogenic differentiation of human hFOB 1.19 osteoblasts through miR-223-3p, which may be related to the inhibition of FOXO3 expression by miR-223-3p.

Keywords

• chronic obstructive pulmonary disease
• exosomes
• osteogenic differentiation
• mir-223-3p