Correlation of phosphorus-31 magnetic resonance spectroscopy and morphologic findings in Alzheimer's disease
J. W. Pettegrew, K. Panchalingam, J. Moossy, J. Martinez, G. Rao and F. Boller
Department of Psychiatry, University of Pittsburgh, PA.
Senile plaques (SPs), especially, and neurofibrillary tangles are important
pathologic markers for the diagnosis of Alzheimer's disease (AD), but
neither is pathognomonic for AD. We hypothesize that elevations in levels
of phosphomonoesters, precursors of membrane phospholipids, occur early in
the pathogenesis of AD and precede the appearance of SPs. In contrast,
elevations in levels of phosphodiesters, breakdown products of
phospholipids, reflect degeneration of neural membranes and will correlate
with the appearance of SPs. Correlative phosphorus-31 magnetic resonance
spectroscopy and morphologic studies conducted to test this hypothesis
disclosed that elevations in levels of phosphomonoesters had a negative
correlation with the numbers of SPs, and elevations in levels of
phosphodiesters had a positive correlation with the numbers of SPs. No
correlations were observed for either membrane parameter and
neurofibrillary tangles. These findings support our hypothesis and suggest
that aberrations in the synthesis of membrane phospholipids are early
metabolic events in the pathogenesis of AD.
