The chemistry of aluminum and silicon in relation to Alzheimer's disease.
Aluminosilicates have been identified at the core of senile plaques in Alzheimer's disease, and aluminum has been found within neurons bearing neurofibrillary tangles. Here we show that aluminum species interact with silicic acid, Si(OH)4--a normal component of plasma--to form aluminosilicate species solubilized by citrate. A switch in the binding of aluminum from silicate to phosphate at pH less than 6.6 calls attention to the strong binding of cationic aluminum species to proximate phosphate groups, as in the inositol phosphates, and to the potential effect on the activity of the phosphoinositide-derived intracellular messenger system. The chemistry may throw light on the debated relationship between aluminum and Alzheimer's disease.
Birchall
J D
JD
Imperial Chemical Industries Plc, Cheshire, U.K.
Chappell
J S
JS
D000535:Aluminum; D000544:Alzheimer Disease / Q000378:metabolism*; D055598:Chemical Phenomena; D011232:Chemical Precipitation; D002621:Chemistry; D002951:Citrates / Q000494:pharmacology; D019343:Citric Acid; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010710:Phosphates; D012824:Silicic Acid; D012822:Silicon Dioxide; D012996:Solutions
D002951:Citrates; D010710:Phosphates; D012996:Solutions; D012824:Silicic Acid; D019343:Citric Acid; D012822:Silicon Dioxide; D000535:Aluminum