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The data obtained by transcriptome analysis of lumbar spinal cord segments, sciatic nerve, and the respiratory diaphragm of the mice performed after a space flight on board Bion-M1 biosatellite were processed by bioinformatic methods aimed at elucidation of the regularities in hypogravity-induced transcriptome changes in various compartments of motor neurons. The study revealed abnormalities of axonal transport in spinal motor neurons provoked by weightlessness. These data agree with the results of electron microscopy examination of the spinal cord in experimental animals. In space group mice sacrificed on the landing day, the content of perinuclear ribosomes in lumbar motoneurons surpassed that in control mice or in the recovery group examined 1 week after the flight. The data corroborate our hypothesis on contribution of axonal transport disturbances into pathogenesis of hypogravity motor syndrome. They can be employed as a launching pad for further study of hypogravity-triggered motor disorder mechanisms in order to elaborate the preventive therapy against the development of hypogravity motor syndrome in space flights.

Clastogenic and anticlastogenic activity of glucocorticoid hormones hydrocortisone, prednisolone, and dexamethasone was studied by counting chromosome aberrations in Crepis capillaris test system. Hydrocortisone in a concentration of 12.5 mg/ml produced a clastogenic effect and increased the number of chromosome aberrations in comparison with spontaneous level. Hydrocortisone (6.25 and 3.13 mg/ml), prednisolone (15, 7.5, and 3.75 mg/ml), and dexamethasone (1, 0.5, 0.25, and 0.125 mg/ml) exhibited an anticlastogenic effect and reduced ethyl methanesulfonate-induced mutagenesis.

Anticlastogenic properties of plasma and proteins (albumin and gamma-globulin) of the human blood were studied using seeds of Crepis capillaris (chromosome aberration assay). Antimutagen p-amino-benzoic acid was used as a comparative reagent. Anticlastogenic activity dependent of processing conditions of the biosubstrate used; for the pre-processing and combined processing anticlastogenic effect was higher than for post-processing, the processing properties of the blood being higher than those of the blood proteins. Anticlastogenic potential of biosubstrates did not depend on mutation inductor. Complex-formimg properties of plasma and blood albumen have been revealed using spectrop-hotometry through the substantial spectral displacement--relative to the expected spectrum--for the mixture of biosubstrata and mutagens. Using chemoluminescence, all plasma, albumin and gamma-globulin concentrations have been shown to enhance generation of hydroxyl radical of the Fenton reagent, especially for albumin in 1.0 g/l concentration. The general trend for all experiments was that the said substances diminished the stimulating effect as their concentrations grew. Peroxidation of yolk lipoproteids showed that only high concentrations of blood's plasma and albumen have antioxidizing properties. gamma-Globulin did not reveal any ability to inhibit lipid peroxidation of yolk lipoproteids. Complex-forming mechanisms of blood's albumen and antioxidizing property of human plasma and proteins have been proved to form the blood's anticlastogenic potential.

Mutagenic and antimutagenic properties of humans, bull, rabbit, chick, rat, and mouse were studied using seeds of Crepis capillaries (the chromosome aberration test). Antimutagenic activity was found in pre-processing, combined, and post-processing conditions of the seeds with a blood relative to the mutation inductors. Whole human and animal blood was found to be capable of inducing chromosome aberrations far exceeding the level of spontaneous mutations. Dilution of the blood did not eliminate its antimutagenic activity.

The seeds of Crepis capillaris were used to examine the mutagenic und antimutagenic properties of human whole blood, plasma, serum albumin and gamma-globulin by recording chromosomal and chromatid aberrations. The antimutagenic activity was determined by preliminary, simultaneous, and subsequent biosubstrate treatments of the seeds. The whole and twice-diluted blood, as well as plasma, induced aberrations exceeding the level of self-arbitrary mutagenesis by 3.7-5.3 and 2.6-3.1 times, respectively. When the blood was diluted to its 20% concentration, the antimutagenic efficiency of biological fluids was recorded. Human serum albumin and gamma-globulin were found to have an antimutagenic effect. In the dilutions having no antimutagenic effect, blood, plasma, and albumin showed their ability to be effectively decrease the level of induced aberrations.