Extracts of Phlomoides umbrosa Turczaninow alleviate allergic airway inflammation in lipopolysaccharide-stimulated RAW 264.7 cells and ovalbumin-induced hyper-responsiveness mouse model

Phlomoides umbrosa Turczaninow (PU), a traditional Korean medicinal herb, exhibits osteogenic and anti-inflammatory effects. This research explored the effect of PU extracts on hyperimmune responses within the respiratory tract using lipopolysaccharide-stimulated RAW 264.7 cells and an ovalbumin-induced hyper-responsiveness model. The inflammatory cytokines, protein expression linked to airway inflammation, antioxidant enzyme activity, histopathological observation, and expectorant activity were measured. The results revealed that PU treatment led to a concentration-dependent reduction in Th2 cytokines and the expression of nuclear factor (NF)-κB, phosphatase-tensin homolog, mitogen-activated protein kinase (MAPK), and inducible nitric oxide synthase (iNOS). Simultaneously, antioxidant enzyme activity increased. Furthermore, PU exhibited substantial enhancements in lung tissue condition and expectorant activity relative to the allergic rhinitis-induced group. These findings indicate the potential of PU to mitigate airway inflammation and excessive mucus production by suppressing NF-κB, MAPK, and iNOS pathways. Consequently, PU emerges as a promising anti-inflammatory agent for respiratory tract applications.