Morphological and Physiological Changes in Mature In Vitro Neuronal Networks towards Exposure to Short-, Middle- or Long-Term Simulated Microgravity
Figure 6
Altered viability induced during and after simulated microgravity exposure.
(A) Percentage of Ann V+-PI− and Ann V+-PI+ cells in neuronal network induced after 1 hour, 24 hours or 10 days of simulated microgravity. (B) RPM/GC ratios of total Ann V+ percentages of neuron cultures exposed and not exposed to simulated microgravity. (C) Percentages of Ann V+-PI− and Ann V+-PI+ cells in neuron cultures exposed to RPM and having recovered for 24 h in ground conditions. (D) Percentages of Ann V+-PI− and Ann V+-PI+ cells in neuron cultures exposed to RPM and having recovered for 72 h in ground conditions. (E) RPM/GC ratios of total Ann V+ percentages of neuron cultures recovered for 24 and 72 hours after simulated microgravity exposure. * = p<0.05 24 h compared to 72 h. (F) Neurons stained with Annexin V-FITC/PI/Hoechst (green/red/blue) and observed under fluorescence microscope. Ann V-FITC−/PI−/Hoechst+ are considered healthy cells, V-FITC+/PI−/Hoechst+ are considered early apoptotic cells and Ann V-FITC+/PI+/Hoechst+ are considered late apoptotic or necrotic cells. Paired two-tailed Student’s t-test and standard deviation bars are shown. 1, p<0.05 Ann V+-PI− RPM compared to GC; 2, p<0.05 Ann V+-PI+ RPM compared to GC; 3, p<0.05 total Ann V+ RPM compared to GC. GC = ground conditions; RPM = Random Positioning Machine.