The presence of lipopolysaccharides from T. denticola, T. forsythia and P. gingivalis in the brain, which can be associated with increased expression of major proinflammatory cytokines (IL-1β, IL-6 and TNFα) and decreased expression of antiinflammatory cytokines (IL-10), suggest a role for the interaction of inflammatory markers in the development and progression of AD (63, 64). Here, TNF is linked to Alzheimer disease.