Detection of Renal Tissue and Urinary Tract Proteins in the Human Urine after Space Flight

Abstract

The urine protein composition samples of ten Russian cosmonauts (male, aged of 35 up to 51) performed long flight missions and varied from 169 up to 199 days on the International Space Station (ISS) were analyzed. As a control group, urine samples of six back-up cosmonauts were analyzed. We used proteomic techniques to obtain data and contemporary bioinformatics approaches to perform the analysis. From the total number of identified proteins (238) in our data set, 129 were associated with a known tissue origin. Preflight samples contained 92 tissue-specific proteins, samples obtained on Day 1 after landing had 90 such proteins, while Day 7 samples offered 95 tissue-specific proteins. Analysis showed that consistently present proteins in urine (under physiological conditions and after space flight) are cubilin, epidermal growth factor, kallikrein-1, kininogen-1, megalin, osteopontin, vitamin K-dependent protein Z, uromodulin. Variably present proteins consists of: Na(+)/K(+) ATPase subunit gamma, β-defensin-1, dipeptidyl peptidase 4, maltasa-glucoamilasa, cadherin-like protein, neutral endopeptidase and vascular cell adhesion protein 1. And only three renal proteins were related to the space flight factors. They were not found in the pre-flight samples and in the back-up cosmonaut urine, but were found in the urine samples after space flight: AFAM (afamin), AMPE (aminopeptidase A) and AQP2 (aquaporin-2). This data related with physiological readaptation of water-salt balance. The proteomic analysis of urine samples in different phases of space missions with bioinformation approach to protein identification provides new data relative to biomechemical mechanism of kidney functioning after space flight.

Investigation of urine proteome of preterm newborns with respiratory pathologies

“…Urine samples of healthy adult volunteers (second morning urine sample, middle stream) were obtained and analyzed in accordance with the protocol developed in our laboratory [23][24][25].…”

“…Urine samples of newborns were prepared according to the protocol described previously [23][24][25], with minor modifications caused by low sample volume. Urine samples (1 mL) were concentrated up to 50 µL using the Vivaspin 4, 10 kDa, PES, tube ("Sartogosm", Russian Federation) at 1000 g for 1 h at 4 0 C and resuspended in the reduction buffer containing 0.2 M Tris-HCl, pH 8.5, 2.5 mM EDTA, 8 M urea to a normalized total protein concentration (Bradford Protein Kit, Bio-Rad) of 10 mg/mL.…”

Determination of proteomic and metabolic composition of exhaled breath condensate of newborns

“…Spectrum of peptides of invariant proteins of 1, 10, 2, and 9 keratins was found in all samples; as is known [9,11,12], they are exogenous proteins. Peptides of nonkeratin components of the protein, the composition of which varies in different patients due to the stage of development and disease, were found in EBC samples (Table 1).…”

“…Concentration was carried out by a favored method of lyophilization, which was previously shown to be the most effective in adult patients [9,10]. Proteome of EBC was analyzed by chromatography-mass spectrometry using the method described earlier [11,12]. Measurements were taken using LTQFT mass spectrometry (Thermo, Germany) and MaXis Impact (Bruker Daltonics, Germany).…”

Preparing normal tissue cells for space flight experiments

“…In addition, the function of kidneys is changed. Urine output in astronauts was low in space on the Russian space station Mir [11] and changes in proteins, related with physiological water-salt balance, were found in post flight urine samples [12]. Moreover, brain changes have been observed in astronauts, which impact functional performance [13].…”