LPS does not modify the BMP-SMAD pathway in ID and control mice. (A) Liver expression of hepcidin (Hamp) mRNA measured by TaqMan–qRT-PCR in 7-week-old mice (10 mice for each group). (B) Analysis of liver SMAD protein activation. Livers were dissociated as described in “Western blot analysis”; extracts were subjected to SDS-PAGE and Western blotted for phospho-SMAD1/5/8 and SMAD5 to normalize gel loading. A representative Western blot is shown. (C) Liver bone morphogenetic protein 6 (Bmp6) expression measured as in panel A. (D) Hamp fold-increase activation by LPS calculated as a ratio between the value of LPS-treated and untreated animals both in IR and ID mice. Liver inhibitor of DNA binding 1 (Id1; E) and Smad7 (F) mRNA expression measured by TaqMan qRT-PCR (10 mice for each group). Hypoxanthine phosphoribosyltransferase 1 (Hprt1) was used as the housekeeping gene to normalize gene expression. mRNA expression ratio was normalized to an IR mean value of 1. Error bars indicate SE; ns, not significant; *P < .05; **P < .005; and ***P < .0001.