Journal: bioRxiv
Article Title: Non-neuronal, TGF-β–driven extracellular matrix restructuring promotes neurodegeneration in a PSP-Richardson syndrome model
doi: 10.1101/2025.08.17.670724
Figure Lengend Snippet: a, Representative images of F-actin staining (phalloidin, red) in MOs primary cultures from healthy controls (HC) and PSP-RS patients. DNA is counterstained in blue (DAPI). Insets show higher magnification of boxed areas. Scale bar, 50 µm. b, Quantification of mean fluorescence intensity (MFI) for F-actin reveals significantly increased actin polymerization in PSP-RS (mean ± s.e.m.; n = 8 images; *** P = 0.0002, unpaired t -test with Welch’s correction). c, Western blot showing reduced expression of actin-capping protein CapZ in PSP-RS compared to HC. d, Western blot of acetylated α-tubulin (Lys40) shows decreased levels in PSP-RS MOs. Uncropped western blot gels are available in Source Data e, Representative images and quantification of RhoA-GTP levels (green) show increased active RhoA in PSP-RS cells (mean ± s.e.m.; n = 60 cells HC, 61 cells PSP; **** P < 0.0001, Mann–Whitney test). DNA, DAPI (blue). Scale bar, 25 µm. f, Treatment of PSP-RS MOs with ROCK inhibitor Y-27632 reduces F-actin intensity (mean ± s.e.m.; n = 8 images HC, 7 images PSP; P = 0.0490, unpaired t -test with Welch’s correction). Scale bar, 50 µm. g, Exogenous TGF-β treatment of HC MOs increases F-actin intensity (mean ± s.e.m.; n = 23 ROIs HC, 24 ROIs HC+TGFβ; ** P = 0.0052, unpaired t -test with Welch’s correction). Scale bar, 50 µm. h, TGF-β I receptor inhibitor SB431542 reduces F-actin intensity in PSP-RS cultures (mean ± s.e.m.; n = 23 ROIs PSP, 26 ROIs PSP+SB; **** P < 0.0001, unpaired t -test with Welch’s correction). Scale bar, 50 µm. Statistics are available in Additional File 2.
Article Snippet: In PSP-RS organoids, TGFβ pathway inhibition was achieved using the selective ALK5 inhibitor SB431542 (10 μM; Miltenyi Biotec).
Techniques: Staining, Fluorescence, Western Blot, Expressing, MANN-WHITNEY