Dynamically regulated miRNA-mRNA networks revealed by exercise

MiRNAs are essential mediators of many biological processes. The aim of this study was to investigate the dynamics of miRNA-mRNA regulatory networks during exercise and subsequent recovery period. Here we monitored the transcriptome changes by microarray analysis of the whole blood of eight highly trained athletes after 30 min of moderate exercise followed by 30 min and 60 min of recovery period. We combined expression profiling and bioinformatics and analysed metabolic pathways enriched with differentially expressed mRNAs and then mRNAs which are known to be validated targets of differentially expressed miRNAs. Finally we revealed four dynamically regulated networks comprising differentially expressed miRNAs and their known target mRNAs with anti-correlated expression profiles over time. The data suggest that hsa-miR-21-5p regulated TGFBR3, PDGFD and PPM1L mRNAs. Hsa-miR-24-2-5p was likely to be responsible for MYC and KCNJ2 genes and hsa-miR-27a-5p for ST3GAL6. The targets of hsa-miR-181a-5p included ROPN1L and SLC37A3. All these mRNAs are involved in processes highly relevant to exercise response, including immune function, apoptosis, membrane traffic of proteins and transcription regulation. We have identified four miRNA-mRNA networks dynamically regulated following exercise. This work is the first study to monitor miRNAs and mRNAs in parallel into recovery period. The results provide a novel insight into the regulatory role of miRNAs in stress adaptation. Each subject performed a treadmill test with an incremental step protocol until exhaustion. Blood samples were taken from the antecubital vein using indwelling catheter before (T1), immediately after ramp test to exaustion (T2) and after 30 min of recovery (T3). Two weeks later, athletes participated in the main exercise, consisting of running at 80% VO2 peak for 30 min on a treadmill. Blood samples were taken from the antecubital vein using indwelling catheter before (T4), immediately after running at 80% VO2 peak for 30 min on a treadmill (T5), after 30 min (T6) and 60 min (T7) of recovery.