Biochem Soc Trans. 2013 Dec;41(6):1588-92. doi: 10.1042/BST20130114.
Astrocytes are considered key regulators of the iron metabolism of the brain. These cells are able to rapidly accumulate iron ions and various iron-containing compounds, store iron efficiently in ferritin and also export iron. The present short review summarizes our current knowledge of the molecular mechanisms involved in the handling of iron by astrocytes. Cultured astrocytes efficiently take up iron as ferrous or ferric iron ions or as haem by specific iron transport proteins in their cell membrane. In addition, astrocytes accumulate large amounts of iron oxide nanoparticles by endocytotic mechanisms. Despite the rapid accumulation of high amounts of iron from various iron-containing sources, the viability of astrocytes is hardly affected. A rather slow liberation of iron from accumulated haem or iron oxide nanoparticles as well as the strong up-regulation of the synthesis of the iron storage protein ferritin are likely to contribute to the high resistance of astrocytes to iron toxicity. The efficient uptake of extracellular iron by cultured astrocytes as well as their strong up-regulation of ferritin after iron exposure also suggests that brain astrocytes deal well with an excess of iron and protect the brain against iron-mediated toxicity.
星形胶质细胞被认为是大脑铁代谢的关键调节者。这些细胞能够快速积累铁离子和各种含铁化合物，有效地将铁储存在铁蛋白中，并将铁输出。本综述总结了我们目前对星形胶质细胞处理铁的分子机制的认识。培养的星形胶质细胞通过细胞膜上的特定铁转运蛋白有效地摄取亚铁或三价铁离子或血红素。此外，星形胶质细胞通过内吞作用机制积累大量氧化铁纳米颗粒。尽管从各种含铁来源快速积累大量铁，但星形胶质细胞的活力几乎不受影响。从积累的血红素或氧化铁纳米颗粒中缓慢释放铁以及铁储存蛋白铁蛋白的强烈上调可能有助于星形胶质细胞对铁毒性的高抗性。培养的星形胶质细胞对细胞外铁的有效摄取以及铁暴露后铁蛋白的强烈上调表明，脑星形胶质细胞能够很好地处理过量的铁，并防止铁介导的毒性对大脑造成损害。
