Changes in the urinary proteome in rats with regular swimming exercise

PURPOSE: Urine can sensitively reflect early pathophysiological changes in the body. The purpose of this study was to explore the changes of urine proteome in rats with regular swimming exercise. METHODS: In this study, experimental rats were subjected to daily moderate-intensity swimming exercise for 7 weeks. Urine samples were collected at weeks 2, 5, and 7 and were analyzed by using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). RESULTS: Unsupervised clustering analysis of all urinary proteins identified at week 2 showed that the swimming group was distinctively different from the control group. Compared to the control group, a total of 112, 61 and 44 differential proteins were identified in the swimming group at weeks 2, 5 and 7, respectively. Randomized grouping statistical analysis showed that more than 85% of the differential proteins identified in this study were caused by swimming exercise rather than random allocation. According to the Human Protein Atlas, the differential proteins that have human orthologs were strongly expressed in the liver, kidney and intestine. Functional annotation analysis revealed that these differential proteins were involved in glucose metabolism and immunity-related pathways. CONCLUSION: Our results revealed that the urinary proteome could reflect significant changes after regular swimming exercise. These findings may provide an approach to monitor the effects of exercise of the body.