HIF-PHIs suppress hepcidin expression in a manner dependent on the induction levels of EPO and erythroferrone expression. Scatter plots of the relationships between EPO concentrations in plasma (Figure 1A), Fam132b (erythroferrone) mRNA levels in the bone marrow, Fam132b mRNA levels in the spleen, and Hamp (hepcidin) mRNA levels in the liver (Figure 2). The correlations between the parameters in each graph were analyzed with the Pearson correlation coefficient in the control (green) and mutant (ISAM, blue; AnRED, red) mouse lines, which were treated with vehicle (circles), GSK360A (triangles), or roxadustat (crosses).