1 April 2012
I read about the effects of aluminum on brain with features of aging and calcium signaling with interest . The effects of aluminum on the brain in the pathogenesis of Alzheimer’s disease (AD) may play out at the blood brain barrier. Aluminum enhances the permeability of the blood-brain barrier to lipophilic substances  and the central part of the amyloid-β peptide (Aβ), the alpha helical antigenic folding domain of the Aβ folding peptide loop is lipophilic . Studies have indicated that some of the Aβ present in AD patients was from peripheral blood, and endogenous bloodborne Aβ has been found to cross the blood-brain barrier by a non-saturable mechanism .
Aβ and hyperphosphorylated tau deposits have been found in the pancreas of patients with type 2 diabetes . Aβ may escape into the circulation from the pancreas, especially in patients with type 2 diabetes, and cross the blood-brain barrier, especially if it has been primed by aluminum exposure, which increases its permeability to lipophilic substances such as Aβ. The increased brain exposure to Aβ may in turn cause increased likelihood of developing AD in susceptible individuals.
Although the effect of aluminum on development of AD remains controversial, certainly increased amounts of Aβ are thought to increase the likelihood of developing AD. If the blood-brain barrier is exposed to aluminum, it may in turn cause increased amounts of Aβ to accumulate in the brain with subsequent neurotoxicity and development of AD. Aluminum is not necessarily toxic in its own right, but may cause increased exposure of the brain to the neurotoxin, Aβ, one of the main components of AD, by permitting it to pass through the blood-brain barrier at an increased rate.
Steven R. Brenner, MD
Affiliated with St. Louis University
Department of Neurology and Psychiatry
St. Louis, MO, USA
 Walton JR (2012) Aluminum disruption of calcium homeostasis and signal transduction resembles change that occurs in aging and Alzheimer’s disease. J Alzheimers Dis 29, 255-273.
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