Ricerc@Sapienza

The determination of the function of cells in zero-gravity conditions is a subject of interest in many different research fields. Due to their metabolic unicity, the characterization of the behaviour of erythrocytes maintained in prolonged microgravity conditions is of particular importance. Here, we used a 3D-clinostat to assess the microgravity-induced modifications of the structure and function of these cells, by investigating how they translate these peculiar mechanical stimuli into modifications, with potential clinical interest, of the biochemical pathways and the aging processes.

The direct impact of microgravity exposure on male germ cells, as well as on their malignant counterparts, has not been largely studied. In previous works, we reported our findings on a cell line derived from a human seminoma lesion (TCam-2 cell line) showing that acute exposure to simulated microgravity altered microtubule orientation, induced autophagy, and modified cell metabolism stimulating ROS production. Moreover, we demonstrated that the antioxidant administration prevented both TCam-2 microgravity-induced microtubule disorientation and autophagy induction.

Metazoan living cells exposed to microgravity undergo dramatic changes in morphological and biological properties, which ultimately lead to apoptosis and phenotype reprogramming. However, apoptosis can occur at very different rates depending on the experimental model, and in some cases, cells seem to be paradoxically protected from programmed cell death during weightlessness.

The recently renewed focus on the human exploration of outer space has boosted the
interest toward a variety of questions regarding health of astronauts and cosmonauts.
Among the others, sleep has traditionally been considered a central issue. To extend
the research chances, human sleep alterations have been investigated in several
analog environments, called ICEs (Isolated, Confined, and Extreme). ICEs share different
features with the spaceflight itself and have been implemented in natural facilities and

Convective boiling in reduced diameter channels has been presented as an efficient way of cooling high heat fluxes generated by electronic components. In this context, a large number of authors have dedicated their efforts to study this heat transfer mechanism in normal gravity conditions. However, in space applications under microgravity conditions, and in aircrafts, which have variations in a range of acceleration in that fluid is undergoing, the number of studies is reduced.

Many pivotal biological cell processes are affected by gravity. The aim of our study was to evaluate biological and functional effects, differentiation potential and exo-metabolome profile of simulated microgravity (SMG) on human hepatic cell line (HepG2) and human biliary tree stem/progenitor cells (hBTSCs). Both hBTSCs and HepG2 were cultured in a weightless and protected environment SGM produced by the Rotary Cell Culture System (Synthecon) and control condition in normal gravity (NG).

Cells in simulated microgravity undergo a reversible morphology switch, causing the appearance of two distinct phenotypes. Despite the dramatic splitting into an adherent-fusiform and a floating-spherical population, when looking at the gene-expression phase space, cell transition ends up in a largely invariant gene transcription profile characterized by only mild modifications in the respective Pearson’s correlation coefficients.

Different cell lineages growing in microgravity undergo a spontaneous
transition leading to the emergence of two distinct phenotypes. By returning
these populations in a normal gravitational field, the two phenotypes
collapse, recovering their original configuration. In this review, we hypothesize
that, once the gravitational constraint is removed, the system freely
explores its phenotypic space, while, when in a gravitational field, cells are
“constrained” to adopt only one favored configuration. We suggest that the