SIS3, a specific inhibitor of smad3, attenuates bleomycin-induced pulmonary fibrosis in mice.

Pulmonary fibrosis (PF) is a fatal respiratory disease with no effective medical treatments available. TGF-β/Smads signaling has been implicated to play an essential in the pathogenesis of PF, in which Smad3 act as the integrator of pro-fibrosis signals. In this study, we determined the effect of SIS3, a specific inhibitor of Smad3, in an experimental mouse model of lung fibrosis.

Interleukin 37 promotes angiogenesis through TGF-β signaling.

IL-37 is a novel pro-angiogenic cytokine that potently promotes endothelial cell activation and pathological angiogenesis in our previous study, but the mechanisms behind the pro-angiogenic effect of IL-37 are less well understood. Extending our observations, we found that TGF-β interacts with IL-37, and potently enhances the binding affinity of IL-37 to the ALK1 receptor complex, thus allowing IL-37 to signal through ALK1 to activate pro-angiogenic responses. We further show that TGF-β and ALK1 are required in IL-37 induced pro-angiogenic response in ECs and in the mouse model of Matrigel plug and oxygen-induced retinopathy.

IL-37 impairs host resistance to Listeria infection by suppressing macrophage function.

Listeria monocytogenes is a Gram-positive intracellular bacterium that was transmitted through contaminated food and causes sepsis and even death. IL-37 has been described as an important anti-inflammatory factor, but little is known about the function of IL-37 in host defense against Liseria monocytogenes (Lm) infection. In mice model of systemic infection, we found that mice treated with IL-37 were more sensitive to Lm infection compared with PBS-treated mice.