Effects of S100B on Serotonergic Plasticity and Neuroinflammation in the Hippocampus in Down Syndrome and Alzheimer's Disease: Studies in an S100B Overexpressing Mouse Model

Figure 8

Tau-2-IR in the hippocampus of a one-year-old S100B transgenic animal. The antibody used in these studies recognizes a hyperphosphorylated form of tau usually associated with neurofibrillary tangles. In the developing brain, S100B promotes neurite outgrowth. However, in a brain chronically exposed to elevated levels of S100B, the neurites become dystrophic. (a) Cell body staining in pyramidal neurons of CA3, presumably to intracellular neurofibrillary tangles, 400X. (b) Neuropil threads in the lower blade of the dentate gyrus showing axonal accumulation of tau-2-IR, 600X. (c) Neuritic plaque in CA1 of stratum radiatum. This is a dense accumulation of neuritic fibers, similar to that described for this antibody in human AD subjects, associated with high levels of S100B (Sheng et al. [82]), 600X.