NEFL and Alzheimer disease: These results also support the hypothesis that GI-tract derived, microbial neurotoxins such as LPS affect the efficient readout of AD-relevant neuronal-specific genetic information, such as that from the NF-L gene, and progressively contribute to cytoarchitectural aberrations, neuronal atrophy, and synaptic disorganization all of which are characteristic features of the sporadic AD brain (Figure 6).