Effects of endurance exercise on the urinary proteome analyzed by 2-D PAGE and Orbitrap MS

Exercise-induced proteinuria is a well-known phenomenon and the influence of parameters such as intensity and duration was studied extensively. Usually, total protein or albumin was measured for diagnosis of a proteinuria, and the present study was performed to search for qualitative differences in the urinary proteome before and after endurance exercise.

Urine samples were concentrated and proteins separated by means of 2-D PAGE. Proteins differing in the investigated groups were identified by nano-UPLC-Orbitrap MS after trypsin digestion.

The study yielded several proteins such as hemopexin, albumin, orosomucoid 1, transferrin or carbonic anhydrase 1 that were elevated after a marathon run in comparison to a control group. These are linked to physiological changes resulting from endurance exercise such as destruction of erythrocytes or increased fat metabolism. On the contrary, 2-D PAGE profiles of athletes at rest did not differ from those of control samples.

The study is a starting point to build up individual 2-D PAGE protein maps of athletes. Further studies will investigate intra-individual differences and further exercise parameters, which potentially lead to a physiological monitoring system for athletes in training and competition and may also complement the blood passport in doping control.