Lithospermum erythrorhizon extract inhibits Der p2-induced inflammatory response through alleviation of thymic stromal lymphopoietin, nuclear factor Kappa B, and inflammasome expression in human bronchial epithelial cells

Ethnopharmacological relevance: Lithospermum erythrorhizon (LE) and Angelica sinensis (AS), widely used in several folk medicine for wound, pus discharge and dermatitis for the history of several hundred years in Asian countries. Aim of study: To investigate the therapeutic effect of LE and AS on Der p2-induced inflammatory response in human bronchial epithelial (SEAS-2B) cells. Methods: The effects of Der p2 stimulation on thymic stromal lymphopoietin (TSLP), the nuclear factor kappa B (NF-kappa B) pathway, the inflammasome (specifically, the apoptosis speck-like protein [ASC] and nod-like receptor 3 [NLRP3]), Caspase-1 and the signal transducer and activator of transcription (STAT) 3 pathway were evaluated in the human bronchial epithelial (SEAS-2B) cells. Results: The results indicated that LE, AS, and LE+AS reduced TSLP, I kappa B kinase-a, and NLRP3 levels; LE and AS reduced Caspase-1; LE and LE+AS also reduced NF-kappa B p50, NF-kappa B p65, ASC, and STAT3 levels. Conclusion: Both LE and AS aqueous extracts exert anti-inflammatory effects in Der p2-stimulated BEAS-2B cells. These effects may involve multiple mechanisms, including the inhibition of TSLP production as well as the suppression of IKKa, Caspase-1 and NLRP3; however, additional studies are warranted to elucidate the underlying mechanisms.