Vanadium Carbide Nanosheets with Broad-Spectrum Antioxidant Activity for Pulmonary Fibrosis Therapy

Idiopathic pulmonary fibrosis is a chronic and highly lethal lung disease that largely results from oxidative stress; however, effective antioxidant therapy by targeting oxidative stress pathogenesis is still lacking. The big challenge is to develop an ideal antioxidant material with superior antifibrotic effects. Herein, we report that VC nanosheets (NSs) can serve as a potential antioxidant for treatment of pulmonary fibrosis by scavenging reactive oxygen and nitrogen species. Interestingly, subtle autoxidation can adjust the valence composition of VC NSs and significantly improve their antioxidant behavior. Valence engineering triggers multiple antioxidant mechanisms including electron transfer, H atom transfer, and enzyme-like catalysis, thus endowing VC NSs with broad-spectrum, high-efficiency, and persistent antioxidant capacity. Benefiting from antioxidant properties and good biocompatibility, VC NSs can significantly prevent myofibroblast proliferation and extracellular matrix abnormality, thus alleviating the progression of bleomycin-induced pulmonary fibrosis by scavenging ROS, anti-inflammation, and rebuilding antioxidant defenses. This study not only provides an important strategy for designing excellent antioxidant nanomaterials, but also proposes a proof-of-concept demonstration for the treatment of pulmonary fibrosis and other oxidative stress-related diseases.