Supramolecular Nanofibers Ameliorate Bleomycin‐Induced Pulmonary Fibrosis by Restoring Autophagy

Abstract

Abstract Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal interstitial lung disease, with limited therapeutic options available. Impaired autophagy resulting from aberrant TRB3/p62 protein‐protein interactions (PPIs) contributes to the progression of IPF. Restoration of autophagy by modulating the TRB3/p62 PPIs has rarely been reported for the treatment of IPF. Herein, peptide nanofibers are developed that specifically bind to TRB3 protein and explored their potential as a therapeutic approach for IPF. By conjugating with the self‐assembling fragment (Ac‐GFFY), a TRB3‐binding peptide motif A2 allows for the formation of nanofibers with a stable α‐helix secondary structure. The resulting peptide (Ac‐GFFY‐A2) nanofibers exhibit specific high‐affinity binding to TRB3 protein in saline buffer and better capacity of cellular uptake to A2 peptide. Furthermore, the TRB3‐targeting peptide nanofibers efficiently interfere with the aberrant TRB3/p62 PPIs in activated fibroblasts and fibrotic lung tissue of mice, thereby restoring autophagy dysfunction. The TRB3‐targeting peptide nanofibers inhibit myofibroblast differentiation, collagen production, and fibroblast migration in vitro is demonstrated, as well as bleomycin‐induced pulmonary fibrosis in vivo. This study provides a supramolecular method to modulate PPIs and highlights a promising strategy for treating IPF diseases by restoring autophagy.

Keywords

• autophagy
• peptide nanofiber
• protein‐protein interactions
• pulmonary fibrosis
• self‐assembly