AUTHOR=Lee Ba-Wool , Ha Ji-Hye , Yi Da-Hye , Kim Ju-Hong , Jeong Seong-Hun , Lee Hyeon Jin , Kim Yun-Hye , Kwon Hyung-Jun , Park Ji-Young , Kim Woo Sik , Ryu Young-Bae , Lee In-Chul TITLE=Spiraea prunifolia var. simpliciflora leaves ameliorate inflammatory responses and oxidative stress in PPE/LPS-induced chronic obstructive pulmonary disease mouse model JOURNAL=Frontiers in Pharmacology VOLUME=Volume 16 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2025.1501731 DOI=10.3389/fphar.2025.1501731 ISSN=1663-9812 ABSTRACT=Spiraea prunifolia: var. simpliciflora (SP) is a known medical food that is used to treat emesis, malaria, and fever. This study investigated the therapeutic potential of SP leaf extract on oxidative stress and airway inflammation using a chronic obstructive pulmonary disease (COPD) mouse model induced by porcine pancreatic elastase (PPE) and lipopolysaccharide (LPS). Male C57BL/6N mice were treated intratracheal instillation of PPE (0.05 units/50 μL) and LPS (5 μg/50 μL), and administered positive control (dexamethasone; 3 mg/kg) and SP (50 and 100 mg/kg). SP treatment decreased T helper type 1 (Th-1) cytokines as well as counts of macrophage and neutrophil in bronchoalveolar lavage fluid of PPE/LPS-induced COPD. SP treatment reduced alveolar destruction, inflammatory cell infiltration, and collagen fiber with improvement of forced expiratory volume to forced vital capacity ratio and lung elastance in lung tissue. SP downregulated thioredoxin-interacting protein and NOD-like receptor pyrin domain-containing 3 inflammasome which inhibited caspase-1 and IL-1β expression. SP attenuated production of reactive oxygen and nitric oxide through enhancement of nuclear factor-erythroid 2-related factor translocation with elevation of heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1 expression. Furthermore, SP attenuated the levels of reactive oxygen species and nitric oxide in mice with PPE/LPS-induced COPD. Thus, SP has the therapeutic potential for COPD treatment.