Effects of Scutellaria baicalensis Extract on Cigarette Smoke-Induced Airway Inflammation in a Murine Model of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD), including pulmonary emphysema and chronic bronchitis as well as structural and inflammatory changes in small airways, is insensitive to corticosteroid therapies. This study aimed to evaluate the effects of Scutellaria baicalensis root extract (SB_E) in a mouse model of COPD. The COPD mouse model was produced by challenging C57BL/6 mice with a cigarette smoke extract and lipopolysaccharide (LPS). SB_E significantly decreased the neutrophil counts in blood and bronchoalveolar lavage fluid (BALF), and the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-17A, macrophage inflammatory protein 2 (MIP2), and chemokine (C-X-C motif) ligand 1 (CXCL-1) in BALF, and TNF-alpha mRNA expression in lung tissue. The histological lung injury was also alleviated by treatment with SB_E. Thus, SB_E effectively inhibited airway inflammation by regulating the expression of inflammatory cytokines by blocking MIP2 and CXCL-1 secretion. Therefore, S. baicalensis may be a potential therapeutic agent for COPD.