ETHNOPHARMACOLOGICAL RELEVANCEScutellaria baicalensis Georgi (SCB, Huangqin) is a traditional medicinal plant used to treat fever and respiratory diseases. SCB has a good therapeutic effect on asthma and anti-inflammation in traditional clinic use. However, the molecular mechanism and targets of SCB in treating asthma are still unclear.AIM OF THE STUDYCombining transcriptomic analysis and in vitro experimental validation, this study aimed to reveal the molecular mechanism and targets of SCB in treating asthma.MATERIALS AND METHODSThe anti-asthmatic effects of SCB and its active components, scutellarin and oroxylin A, were evaluated in ovalbumin (OVA)-induced rats by analysis of pulmonary function and pathology. The signaling pathways in rat pulmonary tissue were analyzed using transcriptomics and protein interaction network analysis. Calcium mobilization assay and molecular docking were utilized to discover the active compounds from SCB with agonism activity of type 2 taste receptors (TAS2Rs). The anti-asthmatic effect and transcriptional regulation of TAS2Rs regulated by SCB and its active components were analyzed in vitro.RESULTSExtracts of SCB (ESB), scutellarin, and oroxylin A ameliorated airway function and inflammation in OVA-induced rats. The anti-asthma mechanism of ESB, scutellarin and oroxylin A was highly related to immune and taste transduction pathways based on transcriptomic analysis, especially the TAS2Rs signaling pathway. ESB was the direct agonist of TAS2R4 and TAS2R14 with EC50 of 209.1 and 217.2 μg/mL based on calcium mobilization assay, respectively. Baicalein was the main active component for TAS2R4 agonism activity, and scutellarin and oroxylin A had weak agonism activity of TAS2R4 and TAS2R14 through calcium mobilization assay and molecular docking. However, scutellarin and oroxylin A significantly upregulated the gene expression of Tas2r108 (the mouse ortholog of the TAS2R4) in lung tissue. ESB, scutellarin, and oroxylin A inhibited LPS-induced lactate dehydrogenase release and gene expression of TNF through transcriptional regulation of TAS2R4 and TAS2R14 on bronchial epithelial cells. ESB and oroxylin A ameliorated IgE-induced β-hexosaminidase release and gene expression of Il4 and Tnf and upregulated gene expression of Tas2r108.CONCLUSIONThese results provided new insight into the anti-asthmatic mechanism of SCB and active components, scutellarin and oroxylin A, through agonism and transcriptional regulation of TAS2Rs to ameliorate allergic airway inflammation.