<i>Isodon Suzhouensis</i> extract interferes with miRNA expression profile for prevention and treatment of chronic obstructive pneumonia disease

Chronic obstructive pulmonary disease (COPD) is a respiratory condition characterized by several symptoms. The pathogenesis of COPD is complex and involves multiple factors. A fantastic drug from traditional Chinese medicine, <i>Isodon Suzhouensis</i> (ISZ) is a perennial herb belonging to the Labiaceae family. It has the functions of resolving phlegm, removing stasis, promoting blood circulation and eliminating qi stagnation. ISZ has been found to possess great potential against COPD. Present study is focused on identifying microRNA (miRNA) biomarkers for COPD and determining the role of ISZ leaf extract in regulating the disease through miRNA expression in serum exosomes. The Sprague Dawley (SD) rats were randomly divided into control group, COPD group and COPD + ISZ group. After the establishment of the model, the rats were sacrificed, and the results were compared with the control group. Then the total RNA of rat serum was extracted and identified by nanoparticle tracker. Finally, high-throughput screening and sequencing were performed to screen miRNAs with significant differential expression. Then, different databases were used to figure out the possible target genes, and their functions were assessed by employing Gene Ontology (GO) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The sequencing results were then further verified by qRT-PCR. The results pointed out that these 17 differentially expressed miRNAs may have the potential of diagnostic and prognostic biomarkers against COPD. Interestingly, it was also found that ISZ leaf extract may regulate the occurrence of COPD by affecting the expression of miRNAs. This study identified the biomarkers of COPD and clarified the mechanism of the treatment of COPD by ISZ leaf extract, which is helpful to improve the level of early diagnosis and treatment of COPD.