Variability of urine proteome in healthy humans during a 105-day isolation in a pressurized compartment

Abstract

The protein composition (proteome) of the body fluids is rather flexible; it can change, responding to various factors of the external environment and changes in the internal environment. In order to study the variability of the proteome profile in healthy humans under the conditions of total control of vital rhythm, physical activity, and diet, urine samples were collected from subjects who had been selected according to special criteria and qualified as healthy by a special physical evaluation board. The subjects took part in an experiment with a 105-day-long isolation in a pressurized compartment, carried out by using an autonomous life-support system at the Institute of Biomedical Problems, Russian Academy of Sciences. The purification and concentration of proteins from the urine samples were carried out using a MB-HIC C8 magnetic bead set (Bruker Daltonics). The mass spectra have been obtained using an Autoflex III time-of-flight mass spectrometer (Bruker Daltonics) in the positive lineal mode. One hundred and seventeen peaks were obtained for each urine sample; technological errors of the method have been studied. The high variability of the urine proteome profile (36 protein MC peaks on average) was shown in healthy humans under the conditions of isolation and controlled vital activity.