The effect of iron chelators [desferrioxamine (DFO) and pyridoxal isonicotinoyl hydrazone (PIH)], iron donors [ferric ammonium citrate (FAC) and heme], and the heme precursor, protoporphyrin IX (PIX), on the mRNA levels of frataxin (Frda),transferrin receptor (TfR), Nramp2,β-globin, and β-actin in Friend 707 cells.

Cells were incubated in the presence (+) or absence (−) of 1.5% DMSO for 96 hours at 37°C. After this, the incubation was continued for a further 20 hours at 37°C in the presence or absence of 1.5% DMSO alone (controls) or in these media containing either DFO (100 μM), FAC (100 μg/mL), PIH (50 μM), hemin (50 μM), or PIX (50 μM). Northern blot analysis was performed as described in Figure 2. (A) Ethidium bromide staining of the agarose gel, (B) Frda, (C) TfR, (D) Nramp2, (E) β-globin, and (F) β-actin. The result illustrated is a typical experiment from 4 experiments performed.