Fig. 8

Neurons lacking tau expression are protected from αS PFF-induced loss of dendrites without impacting the development of pS129 αS+ aggregates. a, b Primary mouse hippocampal neurons from nTg (a) and mTau^−/− (b) were induced to develop αS pathology by αS PFF treatment. Same levels of pS129 αS+ aggregates, normalized to MAP2 area,  were seen in nTg (c; P = 0.0001, PBS vs PFF) and mTau^−/− (c; P = 0.0002, PBS vs PFF) neurons 14 days after PFF treatment. pS129 αS+ aggregates normalized to NeuN demonstrated a significant difference between nTg and mTau^−/− (d; P < 0.0001, PBS vs PFF for both nTg and mTau^−/−, and nTg PFF vs mTau^−/− PFF). Analysis of MAP2+ neurites/dendrites at 14 days post-PBS or αS PFF addition to nTg (e) and mTau^−/− (f) neurons. αS PFF treatment led to significant loss of MAP2 area in nTg neurons (e, g; P = 0.0010, PBS vs PFF; P = 0.0004, nTg PFF vs mTau^−/− PFF; P = 0.0230, nTg PFF vs mTau^−/− PBS) but not mTau^−/− primary hippocampal neurons (f, g; P = 0.8297, PBS vs PFF), compared to PBS controls. Abbreviations: phosphate buffered saline, PBS; preformed fibril, PFF; Two-way ANOVA with Sidak’s multiple comparisons test; *P < 0.05, **P < 0.01, and ***P < 0.001. Scale bars = 100 μm;  n = 6–16 randomly selected areas from 3 to 5 independent cultures; error bars represent mean ± SEM