Can Aluminum Pass the Blood Brain Barrier?

An additional area dealing with aluminum in the brain that is currently in question is the extent to which aluminum present in the bloodstream is able to cross into the brain tissue. Aluminum is thought to cross the blood-brain barrier (BBB) by using the iron transport and storage systems because the solution chemistries of aluminum and iron are very similar. The hypothesis is supported by the gradual buildup of aluminum in bone and brain tissue1.

A possible mechanism for crossing the BBB has been suggested as a "Trojan horse" method of transport for aluminum, where aluminum is mistaken for iron, once again because of their similar properties, and brought into the brain from the bloodstream by hematogenous macrophages and monocytes2. It has also been hypothesized that the increased absorption of aluminum in the brain is enhanced by the possible increase in permeability of the BBB as a result of the development of AD.

1 Clauberg M., and Joshi, J.G. "Regulationof serine protease activity by aluminum: Implications for Alzhemer disease." Proceedings of the National Academy of Sciences of the United States of America. 90 (1993) 1009-12.
2 Evans, Peter H. "Aluminum and Trace Element Oxidative Interactions in the Etiopathogenesis of Alzheimers Disease."

Jennifer McGilton
6 November 1997