Fig. 4

Modeled microgravity impaired renal progenitor cell differentiation into podocyte. a Building upon this knowledge and our findings regarding the effects of modeled μg conditions on RPC morphology and function, we sought to investigate the influence of mechanical forces on the differentiation of RPCs into podocytes in the context of reduced mechanical stress due to the unloading conditions modeled by RCCS. modeled μg conditions. BAR = 100 μm. b Growth curves of RPCs cultured in presence of retinoic acid for 72 h at 1 × g and in modeled μg conditions. Data are expressed as mean ± SEM of three independent experiments. c Quantification of the percentage of dead and alive cells determined from confocal images of Calcein-AM/PI staining. Data are expressed as mean ± SEM of three independent experiments. d Measurement of RPC cell area from images. At least 40 cells for each condition were analyzed from three independent experiments. e Confocal images of phalloidin (red fluorescence), and DAPI (light blue) staining in RPCs cultured for 72 h in presence of retinoic acid at 1 × g (right) and in modeled μg (left) conditions. BAR = 25 μm. f Higher magnification of phalloidin staining in RPCs cultured for 72 h in the different conditions. BAR = 25 μm. g Quantification of phalloidin staining. At least 40 cells for each condition were analyzed from three independent experiments. h Images of tubulin (white fluorescence) staining in RPCs cultured for 72 h in the different conditions. BAR = 10 μm. i Images of vimentin (white fluorescence) staining in RPCs cultured for 72 h in the different conditions. BAR = 100 μm. j Expression of nephrin mRNA in RPCs cultured for 72 h in presence of retinoic acid at 1 × g and in modeled μg conditions. Data are expressed as mean ± SEM of three independent experiments. k Confocal images of nephrin expression (green fluorescence) in RPCs cultured for 72 h in presence of retinoic acid at 1 × g and in modeled μg conditions. BAR = 25 μm. l Quantification of nephrin staining. Data are expressed as mean ± SEM of three independent experiments. Statistical analysis was performed using the Mann–Whitney test. m-μg: modeled microgravity