CEREBROSPINAL-FLUID TRANSTHYRETIN - AGING AND LATE-ONSET ALZHEIMERS-DISEASE

The deposition of insoluble beta-amyloid protein fibrils is probably t he central event in the pathogenesis of Alzheimer's disease. Cerebrosp inal fluid inhibits this fibril formation, likely by the intervention of one or several proteins binding to soluble beta-amyloid protein. In vitro, transthyretin (TTR), a CSF protein, impedes amyloid fibrilloge nesis. Lowered concentrations of CSFTTR could therefore be associated with Alzheimer's disease. Concentrations of TTR in CSF samples from 14 9 consecutive patients were assayed, using a kinetic nephelemetric met hod. These concentrations were correlated positively with age, but wer e significantly lower in patients with Alzheimer's disease. These data raise the possibility that amyloid fibril formation could be promoted in patients with late onset Alzheimer's disease by the lack of suffic ient concentrations of TTR.