Concentrations of alpha-tocopherol and its quinone derivative in cerebrospinal fluid from patients with vascular dementia of the Binswanger type and Alzheimer type dementia.

We determined the concentrations of alpha-tocopherol (alpha-TOH) and alpha-tocopherol quinone(alpha-TQ), an oxidized derivative of alpha-TOH, in cerebrospinal fluid from patients with Alzheimer type dementia (ATD) and those with vascular dementia of the Binswanger type (VDBT). Compared with results for the controls, the VDBT patients had unaltered concentrations of alpha-TOH, but a statistically significant, 3.6-fold increase of alpha-TQ (P < 0.01) which was significantly correlated with decreases in the Mini-Mental State Examination scores (P < 0.05). In contrast, ATD patients had significantly decreased concentrations of alpha-TOH (P < 0.01), but had unaltered concentrations of alpha-TQ. These results suggest that there is greater oxidation of alpha-TOH to alpha-TQ in VDBT brain, but are inconclusive about the occurrence of peroxidation in ATD brains.