Figure 1.
Effect of Ac-SDKP on expression of TGF-β receptor type I and II, collagen type I and III in cultured rat fibroblasts.
TGF-β treatment of cultured rat fibroblasts enhanced protein and mRNA levels of TGF-β receptor and increased collagen synthesis, while pretreatment with Ac-SDKP and LY364947 markedly attenuated the effects of TGF-β1. A) Western blot analysis with antibodies against TGF-β receptor type I and II, collagen type I and III; C: control group; T: TGF-β group; T+ LY: TGF-β+ LY364947 group; T+ Ac: TGF-β+ Ac-SDKP group. B) The TGF-β receptor type I protein expression measured by Western blot; C) The TGF-β receptor type II protein expression measured by Western blot; (D) The collagen type I protein expression measured by Western blot; (E) The collagen type III protein expression measured by Western blot; F) The collagen type I mRNA expression measured by Real-time PCR; G) The collagen type III mRNA expression measured by Real-time PCR.
Figure 2.
Effect of Ac-SDKP on expression of α-SMA and SRF in cultured rat fibroblasts.
TGF-β up-regulated the expression of α-SMA in fibroblasts to promote the differentiation from fibroblast to myofibroblast. In contrast, Ac-SDKP and LY364947 pretreatment prevented the α-SMA and SRF expression. A) α-SMA protein expression and distribution as analyzed by immunohistochemistry; B) Western blot analysis with antibodies against α-SMA and SRF; C) α-SMA protein expression measured by Western blot; D) SRF protein expression measured by Western blot; E) α-SMA mRNA expression measured by Real-time PCR; F) SRF mRNA expression measured by Real-time PCR.
Figure 3.
Effect of Ac-SDKP on lung collagen expression in the rat silicotic model.
Compared with control group, the lung collagen content was significantly increased in the rat silicotic model, while Ac-SDKP treatment induced a significant decrease of collagen expression. A) Total collagen content measured by hydroxyproline assay; C4: control 4w group; S4: silicotic model 4w group; C8: control 8w group; S8: silicotic model 8w group; Ac-post: Ac-SDKP post-treatment group; Ac-pre: Ac-SDKP pre-treatment group; B) The tissue extracts were analyzed by Western blot analysis with antibodies against collagen type I and III; C) The collagen type I protein expression measured by Western blot; D) The collagen type III protein expression measured by Western blot.
Figure 4.
Effect of Ac-SDKP on expression of TGF-β1 and its receptor in plasma and lung of rat silicotic model.
Expression of TGF-β1 and its receptor were significantly increased in the silicotic model as compared to control. After the intervention of Ac-SDKP, the expression of these proteins decreased significantly. A) The plasma level of TGF-β1 measured by ELISA; C4: control 4w group; S4: silicotic model 4w group; C8: control 8w group; S8: silicotic model 8w group; Ac-post: Ac-SDKP post-treatment group; Ac-pre: Ac-SDKP pre-treatment group; B) The tissue extracts were analyzed by Western blot analysis with antibodies against TGF-β1 and its receptor; C) TGF-β1 expression protein expression measured by Western blot. D) TGF-β receptor type I protein expression measured by Western blot; C) TGF-β receptor type II protein expression measured by Western blot.
Figure 5.
Effect of Ac-SDKP on expression α-SMA as analyzed by immunohistochemistry in the rat silicotic model.
α-SMA-positive immunostaining was only observed in smooth muscle cells in vessels and trachea in control. Notably, there was more positive expression of α-SMA in silicotic nodules and the area of mesenchyma fibrosis in silicotic model (4w and 8w). Positive expression of α-SMA in Ac-SDKP post- and pre-treatment was less than that in the silicotic model.
Figure 6.
Effect of Ac-SDKP on expression of SRF as analyzed by immunohistochemistry in the rat silicotic model.
SRF-positive immunostaining was only observed in smooth muscle cells in vessels and trachea in control. Notably, there was more positive expression of SRF in silicotic nodules and the area of mesenchyma fibrosis in the silicotic model (4w and 8w). Positive expression of SRF in Ac-SDKP post- and pre-treatment was less than that in the silicotic model.
Figure 7.
Effect of Ac-SDKP on expression of α-SMA and SRF in rat silicotic model.
Expression of α-SMA and SRF was significantly increased in the silicotic model (4w and 8w) as compared to control (4w and 8w). After the intervention of Ac-SDKP, the expression of these proteins decreased significantly. A) The tissue extracts were analyzed by Western blot analysis with antibodies against α-SMA and SRF; B) The α-SMA expression protein expression measured by Western blot. C4: control 4w group; S4: silicotic model 4w group; C8: control 8w group; S8: silicotic model 8w group; Ac-post: Ac-SDKP post-treatment group; Ac-pre: Ac-SDKP pre-treatment group; C) The SRF protein expression measured by Western blot.
Figure 8.
The RAS signal and Ac-SDKP in plasma and lung of rat silicotic model.
Expression of ACE, Ang II and AT1 was significantly increased in the silicotic model (4w and 8w) as compared to control (4w and 8w). Ac-SDKP post- or pre-treatment showed a pattern to decrease the silicosis-induced expression of ACE, Ang II, and AT1, but only inhibition of AT1 expression was statistically significant. A) The plasma level of Ang II measured by ELISA; C4: control 4w group; S4: silicotic model 4w group; C8: control 8w group; S8: silicotic model 8w group; Ac-post: Ac-SDKP post-treatment group; Ac-pre: Ac-SDKP pre-treatment group; B) The level of Ac-SDKP in the lung was measured by ELISA; C) The tissue extracts were analyzed by Western blot analysis with antibodies against ACE, Ang II and AT1; D) The ACE protein expression measured by Western blot. E) The Ang II protein expression measured by Western blot. F) The AT1 protein expression measured by Western blot.