ObjectiveTo study the effect of Buyang Huanwutang on Kelch-like Ech-related protein 1 （Keap1）/nuclear factor E₂-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） antioxidant signaling pathway in rats with idiopathic pulmonary fibrosis （IPF） and explore the mechanism of this prescription in the treatment of IPF. MethodForty SPF-grade male SD rats were assigned into a sham operation group， a model group， a Buyang Huanwutang group， and a nintedanib group according to random number table method， with 10 rats in each group. IPF rat model was established by intratracheal infusion of bleomycin （0.005 g·kg^-1） in other groups except the sham operation group. Buyang Huanwutang group was administrated with Buyang Huanwutang (14.84 g·kg^-1)，intragastric administration of nitedanib suspension (0.1 g·kg^-1)，sham operation group and model group were given equal volume of normal saline， for 28 days. After lung function test， serum and lung tissue samples were collected. Hematoxylin-eosin （HE） staining and Masson trichrome staining were employed to observe the pathological changes of the lung tissue. The content of hydroxyproline （HYP） in lung tissue was detected. The levels of malondialdehyde （MDA） in serum and lung tissue， and the activities of superoxide dismutase （SOD）， glutathione peroxidase （GSH-Px） and catalase （CAT） were determined. The mRNA and protein levels of Keap1， Nrf2， and HO-1 was determined by Real-time fluorescent quantitative polymerase chain reaction， immunohistochemical staining， and Western blot. ResultCompared with the sham operation group， the modeling increased the resistance and elasticity and decreased the compliance of respiratory system （P<0.01）， elevated the lung index， pathological score， and HYP content in lung tissue （P<0.01）， and enriched MDA in serum and lung tissue， while it decreased the activities of SOD， GSH-Px， and CAT （P<0.01）. Furthermore， the modeling down-regulated the mRNA and protein levels of Keap1 and up-regulated those of Nrf2 and HO-1 in lung tissue （P<0.01）. Compared with the model group， Buyang Huanwutang decreased the resistance and elasticity and increased the compliance of respiratory system （P<0.01）， lowered the lung index， pathological score， and HYP content in lung tissue （P<0.01）， and reduced MDA in serum and lung tissue， while it increased the activities of SOD， GSH-Px， and CAT （P<0.01）. Additionally， Buyang Huanwutang down-regulated the expression of Keap1 and up-regulated that of Nrf2 and HO-1 in lung tissue （P<0.05， P<0.01）. ConclusionBuyang Huanwutang can activate Keap1/Nrf2/HO-1 signaling pathway to enhance the antioxidant capacity and slow down the pathological process of IPF in rats.

Pulmonary blast injury has become the main type of trauma in modern warfare, characterized by externally mild injuries but internally severe injuries, rapid disease progression, and a high rate of early death. The injury is complicated in clinical practice, often with multiple and compound injuries. Currently, there is a lack of effective protective materials, accurate injury detection instrument and portable monitoring and transportation equipment, standardized clinical treatment guidelines in various medical centers, and evidence-based guidelines at home and abroad, resulting in a high mortality in clinlcal practice. Therefore, the Trauma Branch of Chinese Medical Association and the Editorial Committee of Chinese Journal of Trauma organized military and civilian experts in related fields such as thoracic surgery and traumatic surgery to jointly develop the Clinical treatment guideline for pulmonary blast injury ( version 2023) by combining evidence for effectiveness and clinical first-line treatment experience. This guideline provided 16 recommended opinions surrounding definition, characteristics, pre-hospital diagnosis and treatment, and in-hospital treatment of pulmonary blast injury, hoping to provide a basis for the clinical treatment in hospitals at different levels.