EW-7197 inhibits hepatic, renal, and pulmonary fibrosis by blocking TGF-β/Smad and ROS signaling

Abstract

Fibrosis is an inherent response to chronic damage upon immense apoptosis or necrosis. Transforming growth factor-beta1 (TGF-β1) signaling plays a key role in the fibrotic response to chronic liver injury. To develop anti-fibrotic therapeutics, we synthesized a novel small-molecule inhibitor of the TGF-β type I receptor kinase (ALK5), EW-7197, and evaluated its therapeutic potential in carbon tetrachloride (CCl4) mouse, bile duct ligation (BDL) rat, bleomycin (BLM) mouse, and unilateral ureteral obstruction (UUO) mouse models. Western blot, immunofluorescence, siRNA, and ChIP analysis were carried out to characterize EW-7197 as a TGF-β/Smad signaling inhibitor in LX-2, Hepa1c1c7, NRK52E, and MRC5 cells. In vivo anti-fibrotic activities of EW-7197 were examined by microarray, immunohistochemistry, western blotting, and a survival study in the animal models. EW-7197 decreased the expression of collagen, α-smooth muscle actin (α-SMA), fibronectin, 4-hydroxy-2, 3-nonenal, and integrins in the livers of CCl4 mice and BDL rats, in the lungs of BLM mice, and in the kidneys of UUO mice. Furthermore, EW-7197 extended the lifespan of CCl4 mice, BDL rats, and BLM mice. EW-7197 blocked the TGF-β1-stimulated production of reactive oxygen species (ROS), collagen, and α-SMA in LX-2 cells and hepatic stellate cells (HSCs) isolated from mice. Moreover, EW-7197 attenuated TGF-β- and ROS-induced HSCs activation to myofibroblasts as well as extracellular matrix accumulation. The mechanism of EW-7197 appeared to be blockade of both TGF-β1/Smad2/3 and ROS signaling to exert an anti-fibrotic activity. This study shows that EW-7197 has a strong potential as an anti-fibrosis therapeutic agent via inhibition of TGF-β-/Smad2/3 and ROS signaling.

TGF-β Type I Receptor Kinase Inhibitor EW-7197 Suppresses Cholestatic Liver Fibrosis by Inhibiting HIF1α-Induced Epithelial Mesenchymal Transition

“…Previously we reported that ALK5 inhibitor EW-7197 strongly reduced fibrosis in various animal models and organs, including the liver, lung, and kidney at a low dose (0.625 - 5.0 mg/kg) [29]. In this study, we assessed the anti-fibrotic effects of treatment with 20 and 40 mg/kg EW-7197 every other day in BDL rats, with the aim of examining the effects of higher doses of EW-7197 in vivo in order to ensure that such doses have efficacy similar to that of low doses of the drug.…”

“…Therefore, canonical TGF-β signal plays a central role in the molecular pathogenesis of liver fibrosis and might serve as a potential target for treatments for patients with hepatic fibrosis [27]. Recently, synthetic inhibitors of TGF-β have been reported to suppress hepatic fibrosis in experimental animal models [28,29]. …”

“…We previously reported that a novel small-molecule inhibitor of ALK5, EW-7197, inhibited fibrosis in the liver, kidneys, and lungs by inhibiting TGF-β/Smad and ROS signaling [29]. In this study, we investigated the anti-fibrotic effect of EW-7197 (20 and 40 mg/kg) in bile duct-ligated (BDL) rats and showed that the higher dose of EW-7197 inhibited fibrosis by inhibiting HIF1α-induced EMT.…”

Potential Ameliorative Effects of Qing Ye Dan Against Cadmium Induced Prostatic Deficits via Regulating Nrf-2/HO-1 and TGF-β1/Smad Pathways

“…EMT is the process of epithelial cells transform to mesenchymal cells and characterized by diminished production of E-cadherin and over-generation of fibronectin, α-SMA and vimentin [12, 27, 28]. EMT usually participates in wound healing and tissue regeneration.…”

Cytokine and anti-cytokine therapies in prevention or treatment of fibrosis in IBD

“…SD-208 reduced fibroblast activation, phosphorylation of Smad2 and Smad3 proteins, and intestinal wall collagen deposition in both models. 12 Similarly, more recent studies on blockade of TGFbR1 with oral inhibitors have demonstrated efficacy in animal models of renal fibrosis, carbon tetrachloride-or bile duct ligation-induced cirrhosis, 13,14 pressure-overload-induced cardiac fibrosis, 15 and bleomycin-induced pulmonary fibrosis. 16 These agents are currently being investigated in oncologic trials, with pre-clinical testing ongoing for fibrotic disorders.…”