Figure 1.
Schematic diagram of the experiments.
Mice of SF, SFV and backup SF groups were co-adapted in housing groups of 3 mice each, SF mice were adapted to paste food diet, and mice of in vivo subgroups passed through preliminary tests. After transportation to and adaptation at Baikonur, SF mice were flown aboard the Bion-M 1 satellite for 30 days. After landing mice were examined and transported to Moscow, where animals of the in vitro subgroup were dissected, while recovery dynamics was followed in the in-vivo subgroup before dissection 7 days after landing. Ground control experiment replicated the principal stages of the spaceflight experiment.
Table 1.
Key dates of the flight experiment.
Table 2.
Key dates of the on-ground control experiment.
Figure 2.
Habitat interior.
Figure 3.
Metabolic parameters in mice fed pelleted food and paste diet.
Body weight (A), food (B) and water (C) consumption, feces (D) and urine (E) production. Differences significant at p<0.05 are marked with an asterisk. When the paste food diet with high water content was introduced mice displayed an increase in bodyweight, stopped drinking, while diuresis and feces weight were increased indicating excretion of excess water consumed with the paste diet.
Figure 4.
Bodyweight (A) and relative BW change (B) after telemetry probe implantation.
Differences significant at p<0.05 are marked with an asterisk. As can be considered from bodyweight data, acute recovery was over by day 5 after surgery.
Table 3.
The outcome of the pre-flight procedures with mice for in vivo studies.
Figure 5.
Mice bodyweight dynamics after transportation to the launch site.
Differences significant at p<0.05 are marked with an asterisk. Transportation did not seriously affect the mice, as can be concluded from a slight drop of bodyweight and its rapid recovery.
Table 4.
Climate parameters in flight, control experiments and the animal facility.
Figure 6.
A representative photograph of mice in the flight habitats.
Note that mice occupy the floor grid before launch (upper row) and cling to the feeder (lower row) in microgravity. The same cages are shown.
Figure 7.
Mice body weight during training (A) and bodyweight before and after the experiments (B).
The pairs of bars on the (B) panel represent body weight before (left box) and after (right box) the corresponding experiment. Points represent individual mice data, boxes – lower to upper quartile, whiskers – minimum and maximum. Differences significant at p<0.05 are marked with an asterisk.
Figure 8.
Post-flight open field behavior parameters expressed as percent of pre-flight background values.
Total (A), center (B) and periphery (C) distance moved, rearing frequency (D), center entries frequency (E), time in center (F), latency to the first center zone entry (G) and grooming duration (H). SF mice displayed reduced activity compared to any of the control groups (GC, SFV or GCV). Mice housed in habitats (SF and GC) were reluctant to explore the center of the arena. Statistical analysis was performed using Mann-Whitney test (*−p<0.05, **−p<0.01, ***− p<0.005 and ****−p<0.0001, ns – not significant or the p value is indicated).
Table 5.
Open field test.
Table 6.
Number of animals in experimental groups after post-flight adjustment.