TNF and Alzheimer disease: Finally, we report that chronic HHcy caused by a 4-week AD significantly increases expression of TNFα in the endothelium (Hcy vs. AD, p < 0.001) (Figure 7B,F,H) and media (Hcy vs. AD, p < 0.0001) (Figure 7B,F,I) when compared to AA rings incubated with Hcy.