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Updated: Jun 5, 2026
High-resolution Confocal Imaging of the Blood-brain Barrier: Imaging, 3D Reconstruction, and Quantification of Transcytosis
Published on: November 16, 2017
How does iron cross the abluminal membrane of the blood-brain barrier
Qian Guo1,2, Tianying Wang3,4, Zhong-Ming Qian5,6
1Mental Health Center Affiliated to Shanghai University School of Medicine, Shanghai, China. qian_guo@shu.edu.cn.
Abstract:
The process of iron transport across the blood-brain barrier (BBB) includes two transmembrane steps: step 1, iron in circulating blood first passes through the luminal membrane (blood side) of BBB cells; step 2, it then passes through the abluminal membrane of the cell (cerebroside) and eventually enters the brain. Compared with step 1, we know relatively little about the mechanism of step 2. However, a large number of studies conducted in the past two decades since the discovery of ferroportin 1 (Fpn1) in 2000 has greatly enhanced our understanding of this issue. Accumulating evidence suggests that Fpn1 is a key player in step 2 and that Fpn1/hephaestin and/or Fpn1/ceruloplasmin iron export pathways found in the basement membrane of intestinal enterocytes have the same role in step 2. In this Review, we focus on the current understanding of the role of Fpn1 in iron transport across the abluminal membrane of the BBB.
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