Lactobacillus-Fermented Centella asiatica Extract Inhibits Airway Inflammation in Cigarette Smoke Extract/LPS-Induced...

Centella asiatica, a widely used medicinal herb in Oriental and increasingly Western medicine, is applied for wound healing, dermatological disorders, and gastrointestinal illness. We investigated the effects of fermented C. asiatica extract (FCAE), prepared with Lactobacillus, on airway inflammation in a murine model of chronic obstructive pulmonary disease (COPD) induced by cigarette smoke extract (CSE) and lipopolysaccharide (LPS). CSE/LPS stimulation caused marked immune cell infiltration in airways. FCAE (100 and 200 mg/kg) reduced neutrophils in the bronchoalveolar lavage fluid (BALF) by 26.03% and 70.11%, respectively, and decreased activated T cells and B cells in the lung, mediastinal lymph nodes, and Peyer's patches, while inhibiting collagen fibrosis. FCAE significantly reduced IL-1α (32.51%), CXCL1 (47.63%), CXCL2 (45.37%), and TNF-α (39.51%) levels in the BALF compared with the control group. It also downregulated the expression of muc5ac (58.39%), CXCL1 (67.32%), CXCL2 (57.60%), and TNF-α (54.61%) and suppressed p-STAT3 activation by 50.22%. Furthermore, FCAE enhanced tracheal phenol red secretion by 229.62%, indicating expectorant activity. UPLC analysis identified nine components, which, together with FCAE, inhibited RANTES, TNF-α, and IL-6 in inflammation-induced BEAS-2B cells. Overall, FCAE attenuates immune activation and airway inflammation, supporting its potential as a candidate therapy or functional food for respiratory diseases.