31P nuclear magnetic resonance (NMR) spectroscopy of brain in aging and Alzheimer's disease.

Phosphorus-31 (31P) NMR is proving to be a powerful analytical method for investigating molecular/metabolic issues in neural tissues. Recent studies have demonstrated high levels of phosphomonoesters and phosphodiesters in mammalian brain, and revealed the influence of brain maturation, development, and aging on these levels. Preliminary studies in Alzheimer's disease have demonstrated elevated levels of phosphomonoesters and phosphodiesters in the areas of Alzheimer's brain which exhibit neuropathological changes. Moreover, phosphomonoester levels were also elevated in areas of Alzheimer's brain that were devoid of neuropathological changes. These findings suggest that the phosphomonoester elevations in Alzheimer's brain antedate changes in cellular morphology and structure. Abnormalities in protein kinase function could potentially explain these findings, as well as the reported hyperphosphorylation of tau protein in Alzheimer's brain. Recent studies from this laboratory suggest that aluminum could also be involved in the changes in phosphomonoesters and phosphodiesters.