Fig. 6
TSP-1 is released from microglial cells exposed to hyperoxia in vitro, but suppressed by BH4 supplementation. a Representative confocal images showing immunoreactivity of TSP-1 (green) and Iba-1 (red) merged with DAPI (blue and yellow) in microglial cell (SIM-A9) cultures exposed to normoxia (21% O2) or hyperoxia (75% O2) and supplemented with vehicle (PBS 1×, sterile) or with BH4 (100 μM) during 24 h. Scale bar = 100 μm. Protein staining (a) and mRNA expression (b) evaluated by qPCR in TSP-1 and Iba-1 were significantly decreased in microglial cells exposed to hyperoxia and supplemented with BH4. Values in the graphs represent the mean ± SEM of n = 6–8 experiments per group. The fold changes were normalized to 18S as internal control. Significant differences (p value) in the mRNA levels between normoxia and hyperoxia are shown in the graphs; & p < 0.0001 compared to the control, **p < 0.001 and ****p < 0.0001 vs hyperoxia