Solubilization of beta-amyloid-(1-42)-peptide: reversing the beta-sheet conformation induced by aluminum with silicates.

This is the authors' abstract. We don't add key points for this paper.

Plaques are one of the two lesions found in the brain of patients with Alzheimer disease. Using a synthetic peptide corresponding to rat beta-amyloid-(1-42) (beta A4), circular dichroism (CD) analyses were performed to examine the effect of Na4SiO4 on the conformational state produced by Al3+. A previous study on fragments of neuronal proteins involved in tangle formation had shown a conformational transition from a beta-pleated sheet to a soluble random coil upon addition of Na4SiO4. In the present study, CD measurements showed that the beta-pleated sheet conformation of beta A4 induced by Al3+ was reversed to the random coil soluble form by the addition of Na4SiO4. The tight binding of SiO4(4-) with Al3+ provides the mechanism for this transition. These results provide insight into the role of aluminum in the Alzheimer diseased brain and suggests that investigation of the use of silicates as a therapeutic agent.