Treatment of Idiopathic Pulmonary Fibrosis by Inhaled Silybin Dry Powder Prepared via the Nanosuspension Spray Drying Technology

Idiopathic pulmonary fibrosis (IPF) is a kind of life-threatening interstitial lung disease characterized by progressive dyspnea with accurate pathogenesis unknown. At present, heat shock protein inhibitors are gradually used to treat IPF. Silybin, a heat shock protein C-terminal inhibitor, has high safety and good application prospects. In this work, we have developed a silybin powder able to be used for inhalation administration for the treatment of IPF. Silybin powder was prepared by the spray drying method and identified using cascade impactometry, particle size, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) spectroscopy. A rat model of bleomycin-induced IPF was used to assess the effect of inhaled silybin spray-dried powder. Lung hydroxyproline content, wet weight, histology, inflammatory factor expression, and gene expression were examined. The results showed that inhaled silybin spray-dried powder alleviated inflammation and fibrosis, limited hydroxyproline accumulation in the lungs, modulated gene expression in the development of IPF, and improved postoperative survival. The results of this study suggest that silybin spray-dried powder is an attractive candidate for the treatment of IPF.