Abstract
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 (TCM), Isodon Suzhouensis (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 to identify microRNA (miRNA) biomarkers for COPD and to determine the role of ISZ leaves extract in regulating the disease through miRNA expression in serum exosomes. The sprague-dawley (SD) rats were randomly divided into control group, model group and drug groups. After the establishment of the model, the rats were sacrificed and the results were compared with 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 leaves 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 leaves extract, which is helpful to improve the level of early diagnosis and treatment of COPD.