AMPK regulates the anti-pulmonary fibrosis effects of tracheloside

In the context of idiopathic pulmonary fibrosis, where therapeutic options are scarce and often accompanied by severe side effects, innovative treatments have become crucial. Tracheloside (TCL) is well-known for its various medicinal properties, but its exact mechanism of action remains unclear. This study focuses on investigating the effects and potential mechanisms of TCL on bleomycin-induced pulmonary fibrosis in mice. In this study, a bleomycin-induced pulmonary fibrosis model was established in vivo to evaluate the anti-fibrotic and antioxidant effects of TCL. In vitro, Transforming growth factor-β (TGF-β) and matrix stiffness-induced myofibroblast differentiation models were constructed to explore the mechanism of TCL. TCL inhibited bleomycin-induced pulmonary fibrosis. In vitro, TCL activated Adenosine 5‘-monophosphate (AMP)-activated protein kinase (AMPK), blocked TGF-β or matrix stiffness-induced myofibroblast differentiation, reduced Nicotinamide adenine dinucleotide phosphate oxidase isoform 4(NOX4) expression, enhanced antioxidant enzyme expression, and alleviated oxidative stress. Furthermore, the activated AMPK not only inhibited NOX4 expression but also, for the first time, reduced NOX4 activation by competitively binding to p22 phox. In summary, TCL alleviated TGF-β or matrix stiffness-induced myofibroblast differentiation and oxidative stress through the AMPK/NOX4 signaling pathway, thereby exerting anti-fibrotic and antioxidant effects. This provides a novel perspective on the regulation of NOX4 by AMPK.