FIGURE 6.

Blocking capillarization simultaneously reverses the mesenchymal phenotypes of LSECs during liver fibrosis and in vitro culturing. (A,B) Mice bearing CCl₄-fibrosis were treated with DMSO or YC-1. Liver sections were stained by Sirius red or observed under SEM. Sirius red⁺ areas and fenestrae per high power field were quantitatively compared between the two groups (A, n = 6). Serum ALT and AST were determined (B, n = 6). (C) LSECs were isolated from mice in (A) and the expression of α-SMA, SM22, and Col-1 was evaluated by qRT-PCR (n = 4). (D) Colocalization of Lyve1 and α-SMA/Col-1 in the sinusoidal areas is shown and quantitatively compared (n = 4). (E,F) LSECs were cultured in the presence of DMSO or YC-1, and were observed under SEM and light microscope on days 2 and 7 of the culture, respectively. Fenestrae were quantified on day 2 and compared (E, n = 4). Expression of VE-cadherin and mesenchymal markers α-SMA, SM22, and Col-1 on day 7 was determined by Western blotting (F). Bars = means ± SD; *P < 0.05, **P < 0.01, ***P < 0.001 vs. DMSO, using two-tailed t-test for (A–E). (G) Cartoon image shows that capillarized LSECs undergo partial endothelial-mesenchymal transition to actively deposit sinusoidal ECM in liver fibrosis.