Fig. 1.

Simulated microgravity (sMG) decreases cell proliferation without affecting cell viability. a MSCs were subjected to simulated microgravity (sMG) via rotation at a constant 15 RPM for 3 days inside 12.5 cm² sealed flasks. LIV was applied twice daily at 2 h intervals for 3 days outside the incubator at 0.7 g’s and 90 Hz for 20 min. During LIV, all samples were taken out but only sMG + LIV group was vibrated. Samples were collected for analysis 24 h after last LIV treatment. b Comparing the cell proliferation and dead cell to live cell ratio using microscopy indicated less cells in field of view (10 ×), flow cytometry showed that sMG decreases cell proliferation by 2.63-fold (p < 0.01, n = 6/group). Cell death was not different between difference Ctrl and sMG samples (n = 6/group). Group comparisons were made using unpaired T-test (b). *p < 0.05, **p < 0.01, ***p < 0.001, against control and each other