Seizure evolution in a mouse model of West syndrome involves complex and time-dependent synapse remodeling, gliosis and alterations in lipid metabolism
Fig 3
Molecular and structural synaptic remodeling in Cyfip2+/R87C mice during seizure evolution.
(A) Heat maps show qRT-PCR results for DEGs encoding synaptic proteins in the cortex and hippocampus of Cyfip2+/R87C mice compared to WT mice at various ages (n = 6 mice per genotype, two-way ANOVA with Šídák’s multiple comparisons test). Statistical significance of expression differences for each gene between PWK 14 and 28 within Cyfip2+/R87C mice is shown in the ‘PWK 14 vs. 28’ column. (B) Representative western blot images and heat maps display the expression levels of representative synaptic marker proteins in the cortical and hippocampal synaptosomes of Cyfip2+/R87C mice compared to WT mice at different ages (n = 6 to 8 mice per genotype, two-way ANOVA with Šídák’s multiple comparisons test). (C) Representative fluorescence immunohistochemistry images and quantification show changes in excitatory presynaptic (vGluT1) and postsynaptic (Homer1) markers in the hippocampal CA1 region of Cyfip2+/R87C mice compared to WT mice at PWK 14 and 28 (n = 7 to 9 mice per genotype, two-way ANOVA with Šídák’s multiple comparisons test). Images obtained using Imaris software for automated foci counting are also included. Scale bar, 2 μm. A.U. = arbitrary units. (D) Representative transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images and quantification of excitatory (Ex.) and inhibitory (Inh.) synapse numbers in the hippocampal CA1 region of WT and Cyfip2+/R87C mice at PWK 28 (n = 59 to 73 images from 3 mice per genotype, unpaired two-tailed Student t test). Presynaptic boutons form synaptic contacts on dendritic spines in WT mice, whereas in Cyfip2+/R87C mice, they contact dendritic shafts and cluster nearby. PSD, postsynaptic density. Scale bar, 0.5 μm. (E) 3D reconstruction of dendritic segments from CA1 pyramidal neurons in WT and Cyfip2+/R87C mice (left, without axons; right, with axons). The cumulative graph displays the distributions of PSD surface area in WT and Cyfip2+/R87C neurons (n = 46 to 77 PSDs per genotype, Kolmogorov–Smirnov test). *P < 0.05; **P < 0.01; ***P < 0.001. Data are represented as mean ± standard error of the mean. The data underlying this Figure can be found in S1 Data.