Plasma homocysteine levels are not increased in murine models of Alzheimer's disease.

Alzheimer's disease (AD) patients tend to have increased plasma levels of homocysteine. However, it is unclear whether abnormality in homocysteine levels is a primary cause of Alzheimer's disease or a disease marker. In order to investigate the relative impact of Alzheimer's disease on plasma homocysteine levels, total plasma homocysteine levels were evaluated in transgenic mouse models that exhibit abnormalities in their brains that are similar to Alzheimer's patients. No significant difference was observed in blood of murine models compared to control mice, indicating that elevated plasma homocysteine level seems to be a risk marker at the most.