Urinary protein changes in the early phase of smoking-induced Chronic Obstructive Pulmonary Disease in a rat model

Chronic obstructive pulmonary disease (COPD) is a group of severe respiratory diseases. Identifying COPD through early urinary biomarkers by proteomics technology may help to reduce the mortality rate of the disease, improve the quality of life of patients and reduce the burden on society. Urine samples from a COPD rat model induced by smoking were taken at week 2, week 4 and week 8. By LC-MS/MS, 15 differential proteins with human orthologs were identified. After smoking for 2 weeks when there were no significant pathological changes, 8 differential proteins were identified: 2 proteins had been reported to be markers of COPD, while 4 proteins were associated with COPD. After smoking for 4 weeks, which is when slight pathological changes were observed, 7 differential proteins were identified: 3 of them were reported to be associated with COPD, while 1 protein had been reported to be a marker of COPD. After smoking for 8 weeks, there were significant pathological changes: 5 differential proteins were identified, 3 of which were reported to be associated with COPD. The results of this study suggest that differential urinary proteins may provide important clues for the early diagnosis of COPD.