Fig. 3: The hippocampal matrix is disrupted in tau-injected mice.
From: Alzheimer’s Tau seeds-induced pathology enhances hippocampal extracellular diffusion
A Aggrecan (yellow) and GFAP (red) signals overlap in specific regions, suggesting that GFAP-positive cells actively engage with and internalise the aggrecan matrix. Scale bar = 200 μm. B 3-D reconstruction from confocal micrographs showing an evident aggrecan internalisation by astrocytes near the AF bodies. C Manders’ coefficient analysis (% of aggrecan signal overlapping with GFAP) shows significantly increased colocalisation in the tau-injected model, suggesting that GFAP-expressing cells internalise the extracellular matrix (mean ± SEM PBS = 0.039 ± 0.002, Tau = 0.08 ± 0.01, Mann-Whitney test p-value = 0.019). D qPCR shows significant upregulation of N-acetylgalactosamine 6-sulfatase (Galns) expression, which plays a key role in the degradation of GAGs. Additionally, we observed a general increase in glycoprotein mRNA levels, with a significant rise in Versican expression (Galns p-value = 0.026, Vcan p-value = 0.039). n = 3 mice. Error bars represent mean ± SD. Created in BioRender. Bezard, E. (2025) https://BioRender.com/b68b484.
