Reliea® combination of Codonopsis lanceolata and Chaenomeles sinensis extract alleviates airway inflammation on particulate matter 10 plus diesel exhaust particles (PM10D) ‑induced respiratory disease mouse model

Particulate matter (PM, diameter < 10 μm) and Diesel exhaust particles (DEP) exposure can cause severe respiratory disorders. This investigation explored the protective effects of Reliea® (RelA), combination of Codonopsis lanceolata and Chaenomeles sinensis extract, against airway inflammation related to PM₁₀D exposure. RelA treatment suppressed reactive oxygen species, nitric oxide release, cytokine expression (IL-6, IL-1β, iNOS, CXCL-2, MCP-1, and TNF-α), and the related inflammatory mechanisms in PM₁₀-induced alveolar macrophage cells. BALB/c mice were injected with PM₁₀D via intranasal trachea three times over a period of 12 days and RelA were orally dispensed for 12 days. RelA inhibited infiltrating neutrophils, total number of immunocytes in lung and bronchoalveolar lavage fluid (BALF). RelA decreased the expression of interleukin (IL)-17, chemokine (C-X-C motif) ligand (CXCL)-1, thymus and activation-regulated chemokine, macrophage inflammatory protein-2, IL-1α, TNF-α, mucin 5AC, cyclooxygenase-2, and transient receptor potential cation channel subfamily A or V member 1 in BALF and lung, and inhibited IL-1α and macrophage marker F4/80 localization in lung of PM₁₀D-induced mice. RelA treatment decreased serum symmetric dimethyl arginine levels. RelA restored histopathological damage via inhibition of NF-κB and MAPK pathways in the trachea and lung. Lancemaside A and protocatechuic acid as major active compounds of RelA was identified. In addition, RelA showed better expectoration through increased phenol red secretion. These results indicate that Reliea® combination of C. lanceolata and C. sinensis extract might be effective in prevention and treatment of airway inflammation and respiratory diseases.