FCCP inhibits HSC proliferation through HO-1. (A) Representative images of cells stained with DAPI (blue fluorescence, left column) and EdU, as a measurement of DNA synthesis (green fluorescence, right column) at day 5. Cells were treated for 5 days with uncouplers (5 μM of each) alone or in combination with the heme-oxygenase inhibitor SnPP as indicated. (B) Quantification of proliferation (EdU positive) as percentage of DAPI positive cells visualized in (A). (C) HO-1 gene expression determined by RT-qPCR during in vitro activation of primary mouse HSCs and comparing 7 day old control cells versus cells treated for 7 days with FCCP or Valinomycin (D). Data are expressed as means of 3 independent experiments ± SEM.