FIG. 7.
Transport of iron to the brain. Iron is exported from endothelial cells of the BBB to brain interstitial fluid through Fpn, and is oxidized to Fe3+ by Cp. Within the brain, iron is bound to Tf or exists as NTBI. Tf bound iron is taken up by TfRs on the neuronal and oligodendroglial plasma membrane. NTBI enters the neuron and astroglia by the DMT1 pathway. Figure adapted from Ke and Qian (224). BBB, blood brain barrier; LDLR, low density lipoprotein receptor; LTF, lactotransferrin; NTBI, non-transferrin bound iron.