Figure 1.
Mice lacking Smad7 develop more severe cardiac dysfunction.
(A) Effect of Smad7 deletion on the systolic blood pressure in response to Ang II infusion. (B) Representative echocardiography at day 28 after saline or Ang II infusion in Smad7 WT and KO mice. Results show that Smad7 KO mice significantly increase LV mass, reduce LVEF and FS when compared with Smad7 WT mice after Ang II infusion. Data represent the mean±SE for a group of 6 mice. **P<0.01, ***P<0.001 vs saline control; ##P<0.01, ###P<0.001 vs Ang II–infused Smad7 WT mice.
Figure 2.
Loss of Smad7 promotes collagen I expression during cardiac fibrosis in response to Ang II infusion.
(A and B) Immunohistochemical staining and quantitative analysis of cardiac collagen I accumulation. (C) Real-time PCR analysis of collagen I (Col-I) mRNA expression. (D and E ) Western blot analysis of collagen I expression. Data represent the mean±SE for a group of 6 mice. *P<0.05, **P<0.01, ***P<0.001 vs saline control; #P<0.05, ###P<0.001 vs Ang II–infused Smad7 WT mice. Scale bar = 100 µm.
Figure 3.
Loss of Smad7 promotes α-SMA expression during cardiac fibrosis in response to Ang II infusion.
(A and B) Immunohistochemical staining and quantitative analysis of cardiac α-SMA accumulation. (C) Real-time PCR analysis of α-SMA mRNA expression. (D and E ) Western blot analysis of α-SMA expression. Data represent the mean±SE for a group of 6 mice. *P<0.05, **P<0.01, ***P<0.001 vs saline control; #P<0.05, ##P<0.01, ###P<0.001 vs Ang II–infused Smad7 WT mice. Scale bar = 100 µm.
Figure 4.
Loss of Smad7 aggravates proinflammation expression during cardiac inflammation in response to Ang II infusion.
(A) IL-1β expression. (B) TNF-α expression. (i) Immunohistochemistry (IHC); (ii) quantitative analysis of immunohistochemical staining (IHC); (iii) real-time PCR analysis. Data represent the mean±SE for a group of 6 mice. *P<0.05, ***P<0.001 vs saline control; #P<0.05, ##P<0.01, ###P<0.001 vs Ang II–infused Smad7 WT mice. Scale bar = 100 µm.
Figure 5.
Loss of Smad7 exacerbates Ang II–induced CD3+ T cell and F4/80+ macrophage infiltration.
(A) Immunohistochemical staining of CD3+ T cells. (B) Immunohistochemical staining of F4/80+ macrophages. Data represent the mean±SE for a group of 6 mice. *P<0.05, **P<0.01,***P<0.001 vs saline control; #P<0.05, ##P<0.01 vs Ang II–infused Smad7 WT mice. Scale bar = 100 µm.
Figure 6.
Disruption of Smad7 enhances Ang II-induced activation of TGF-β/Smad signaling during cardiac fibrosis.
(A) Western blot analysis of Smad7. (B) Western blot analysis of phosphorylated Smad2/3. (C) Immunohistochemical and real-time PCR analysis of TGF-β1 expression. Results show that deletion of Smad7 enhances TGFβ1 expression and Smad2/3 signaling in response to Ang II. Data represent the mean±SE for a group of 6 mice. *P<0.05, ***P<0.001vs saline control; #P<0.05,##P<0.01, ###P<0.001 vs Smad7 WT mice. Scale bar = 100 µm.
Figure 7.
Smad7 deficiency enhances Ang II-induced NF-κB signaling activation, upregulation of Sp1, but loss of miR-29b.
(A) Western blot analysis of phosphorylated IκBα. (B) Western blot analysis of phosphorylated NF-κB/p65. (C) Western blot analysis of Sp1. (D) Real-time PCR analysis of miR-29b expression. Results show that deletion of Smad7 enhances activation of NF-κB signaling by promoting phosphorylation of IκBα and p65, promotes Sp1 expression, but induces loss of cardiac miR-29b. Data represent the mean±SE for a group of 6 mice. *P<0.05, **P<0.01, ***P<0.001vs saline control; #P<0.05,###P<0.001 vs Smad7 WT mice.