[Variability of urine proteome of healthy persons during 105-daily isolation].

Human proteome is very plastic, it changes under the influence of various biological factors. It is of big interest to find out how specific factors of an environment, including a long-term isolation affect on urine proteome. The study was conducted during the experiment with 105-day isolation. In the present investigation we collected urine samples from 6 healthy volunteers (26-41 years old). The physical activity, daily rhythms and diet were controlled. Urine samples were fractionated on magnetic beads MB-HIC C8 (MB - hydrophobic-interaction chromatography) with ClinProt robot (Bruker Daltonics) prior to MALDI-TOF mass spectrometer analysis with Autoflex III TOF/TOF (Bruker Daltonics), working in a positive linear mode. 117 peaks have been obtained in each spectrum of urine. We have shown that even during isolation and under controlled conditions of life a high variability of urine proteome of healthy personas (36 protein MC-peaks in the urine, on average) are revealed.

[Variability in low-molecular subproteome of blood serum of healthy man in normal life conditions].

For analysis of inter-individual variability in low-molecular serum subproteome proteome profiles of healthy men at the age of 20-30 years (36 subjects), 30-40 years (11 subjects) and 40-50 years (11 subjects) were obtained. Serum samples were fractionated on magnetic beads MB WCX using ClinProt robot prior to mass-spectrometry based profiling. Mass-spectra were obtained with time-of-flight mass-spectrometer Autoflex III ("Bruker Daltonics") in automatic mode. It was shown that low-molecular serum subproteome of healthy humans was characterized by significant inter-individual variability. 21% of all peaks in proteome profiles had coefficient of variation more than 50% and 29% of all peaks had low dispersion (CV < 30%).Therefore majority of peaks in proteome profile were peaks with moderate inter-individual variability (CV from 30% to 50%). Fragments of high-molecular kininogen, inter-alpha-trypsin inhibitor, complement components C3 and C4a, apolipoprotein CI, platelet factor IV, beta2-microglobulin and cystatin C showed wide variation among examined groups of healthy men. Dispersion of high-molecular kininogen, inter-alpha-trypsin inhibitor, apolipoproteins AII and CIII peaks increased with age.

[Direct proteome profiling of human blood serum in the experiment with 5-day dry immersion].

Purpose of the investigation was to determine changes in blood plasma proteome in healthy human subjects (n = 14, 19 to 26 y.o.) in an experiment with dry immersion (DI). Plasma samples were drawn 7 and 2 days before the exposure, on DI days 2, 3 and 5, and on days 1, 3, 7 and 15 after the experiment. Previous to direct MALDI-TOF mass-spectrometric profiling, serum samples were pre-fractionated and enriched with magnetic particles MB WCX (WCX--a weak cation exchanger) on ClinProt (Bruker Daltonics). In each spectrum, 175 MS-peaks were detected on average within the mass range from 1000 to 17,000 Da with the signal/noise ratio = 5. Student's criterion (p < 0.05) was used to define reliable differences between DI and baseline samples from 48 peaks (27.4 % of all the proteome profile peaks). On DI days 2 and 3, growth of peak areas was observed in fragments of complement system proteins C3 and C4, high-molecular kininogen and fibrinogen that can be attributed to organism adaptation to conditions of the experiment. Significant increases of the peak area of apolipoprotein CI (reduced form with segregated threonine and proline) and C4 enzymes of the complement system, and fibrinogen on the first day after the experiment can be related to changes in motor activities of the subjects.

Study of normal human serum proteomic profile under conditions of hyperbaric oxygen-nitrogen-argon exposure.

The dynamics of changes in serum proteome was studied under conditions of experimental 9-day seclusion in a pressure chamber at 5 m H(2)O pressure with modified gaseous environment. The proteomic profile for the molecular weight range of 1000-17,000 Da changed by 75%. Increased content of acute phase proteins (complement components, inter-α-trypsin inhibitor, and high-molecular-weight kininogen) was observed on day 1 of the experiment before the exposure. On day 9 of exposure, the peaks of AII, CI, and CII apolipoproteins decreased and angiotensin II peak increased.

[Choice of statistical approaches and analysis of blood serum proteome profiles in an experiment with 24-hour head-down tilt (-15 degrees)].

Variability analysis of normal human proteoma requires a valid and crisp algorithm for mass-spectrometry data analysis. The goal was to test methods of statistical analysis of blood serum proteoma profiles in an experiment with 24-hr. HDT using the small sample nonparametric criteria. The investigation revealed peaks that appear to be a molecular response of organism to simulated microgravity. Further identification of fiducially mobile peaks with the help of tandem mass-spectrometry will enable disclosure of subtle mechanisms of adaptation to the spaceflight factors and improvement of human health evaluation in space missions of varying length.

[Variability of healthy human proteome].

The purpose of this review is to analyze investigations devoted to characteristic of protein variability and diversity of their posttranslational modifications in healthy humans. The numerous researches have demonstrated that proteomic profile has a considerable both intra- and inter-individual variability, and quite often normal variability of some proteins can be comparable to changes observed in pathological processes. Results obtained by our research group have confirmed high intra-individual variability of serum low-molecular subproteome of healthy volunteers, certified by a special medial committee. Proteins characterized by high variability in normal conditions (e.g. haptoglobin--0-40 mg/ml; lysozyme--0,01-0,1 mg/ml; C-reactive protein--0,01-0,3 mg/ml) should be excluded from the list of potential biomarkers. On the contrary, proteins and peptides characterized by insignificant dispersion in healthy population (such as albumin--coefficient of variation (CV) 9%; transferrin--CV14%; C3c complement--CV 17%, alpha-1 acid glycoprotein--CV 21%, alpha2-macroglobulin--CV 20%; transthyretin fragment--CV 28,3% and beta-chain alpha2-HS-glycoprotein--CV 29,7%) can provide us with important information about state of health. Thus investigations of plasticity in proteomic profiles of healthy humans will help to correct reference intervals used in clinical proteomics.