Antifibrotic effects of ambrisentan, an endothelin-A receptor antagonist, in a non-alcoholic steatohepatitis mouse model

Figure 1 Histological analyses of liver tissues. Representative images of hematoxylin-eosin staining (magnification, × 100) in the (A) control and (B) ambrisentan groups; representative images of oil red O staining (magnification, × 100) in the (C) control and (D) ambrisentan groups; E: The proportion (%) of the hepatic steatosis area stained with oil red O was measured using image analysis. Hepatic fibrosis was determined by Sirius red staining. Representative images of Sirius red staining (magnification, × 400) of the (F) control and (G) ambrisentan groups; the proportion (%) of the hepatic fibrosis area stained with Sirius red was measured using image analysis (P < 0.01); H: The area of fibrosis was significantly decreased in the ambrisentan group compared with the control group; I: Comparison of hepatic hydroxyproline content between groups; representative images of α-SMA immunostaining (magnification, × 400) in the (J) control and (K) ambrisentan groups; L: Shows a higher magnification (× 1000) of an α-SMA-positive cell (arrow); M: Quantitation of an area of α-SMA immunostaining measured by image analysis (P < 0.05). The area of α-SMA immunostaining was significantly reduced in the ambrisentan group compared with the control. α-SMA: α-smooth muscle actin.

Figure 2 F4/80 immunostaining. Representative images of F4/80 immunostaining (magnification, × 400) of Kupffer cells in the (A) control and (B) ambrisentan groups; C: Numbers of immunopositive F4/80 cells (arrows) in both groups; representative immunostaining for 8-OHdG (magnification, × 400) in the (D) control and (E) ambrisentan groups; F: Comparison of 8-OHdG-immunopositive cells between the groups; immunostaining for 4-HNE (magnification, × 400) in the (G) control and (H) ambrisentan groups; I: Comparison of 4-HNE-immunopositive cells between the groups. 4-HNE: 4-hydroxynonenal.