Fig. 5.

Thbs1 deficiency in mice results in aortic dissection under pressure overload. (A) Immunostaining of Thbs1 (red) in sham or TAC-operated aortas in WT mice (Top). PLA showing the interaction between Thbs1 and integrin β1 (red dots in Bottom). Right shows highly magnified images of white dashed boxes in Bottom. Arrowheads (white) show PLA cluster. DAPI (blue) and autofluorescence of elastin (green) are also shown. n = 3. (Scale bars, 50 μm.) (B) Kaplan-Meier survival curve for WT (n = 13) and Thbs1KO (n = 22) mice after TAC. *P = 0.043, long-rank test. (C) HW/BW in sham or TAC-operated mice. Bars are mean ± SEM. *P < 0.05, ***P < 0.001, quantification by the Kruskal–Wallis test with Dunn multiple comparisons is shown. The number of animals is indicated in each bar. (D) Hematoxylin and eosin staining of the ascending aortas for histological comparison between sham and TAC-operated aortas. (Scale bars, 100 μm.) (E) Aortic dissection was observed in Thbs1KO ascending aorta proximal to the constriction. (Scale bars, 100 μm.) (F) Morphometric analysis showing the IEL perimeter, outer perimeter, total vessel area, and wall thickness. Bars are mean ± SEM. *P < 0.05, ***P < 0.001, one-way ANOVA. NS: not significant. The number of animals is indicated in each bar. (G) Immunostaining of TAC-operated aortas with YAP (red) in WT and Thbs1KO mice. On the Right, highly magnified images of the white dashed boxes in the adventitial (Adv.) and medial (Med.) layers in the Left are shown. DAPI (blue) and autofluorescence of elastin (green) are also shown. n = 3. (Scale bars, 50 μm.) (H) Representative images of immunohistochemistry for CTGF in TAC-operated aortas of WT and Thbs1KO mice (n = 3 per genotype). The outer elastic lamella as a border between the medial layer and adventitia is shown by the green dashed line. Arrowheads (red) indicate CTGF-positive cells in the medial layer. (Scale bars, 100 μm.)