Discovery and analysis the anti-pseudo-allergic components from Perilla frutescens leaves by overexpressed MRGPRX2 cell membrane chromatography coupled with HPLC-ESI-IT-TOF system

Objectives Screen and identify the anti-pseudo-allergic activity components of Perilla frutescens leaves that interacted with MRGPRX2 (a new reported pseudo-allergic reaction-related receptor). Methods An overexpressed MRGPRX2 cell membrane chromatography (CMC) coupled with HPLC-ESI-IT-TOF system has been established to screen and identify the effective components from P. frutescens leaves. A frontal analysis method was performed to investigate the binding affinity between ligands and MRGPRX2. Their activity of relieving pseudo-allergic reaction was evaluated in vitro by histamine release assay, beta-hexosaminidase release assay and intracellular Ca2+ mobilization assay. Key findings Extract of P. frutescens leaves was proved to be effective in anti-pseudo-allergic reaction by inhibiting MRGPRX2. Apigenin (API) and rosmarinic acid (ROS) were confirmed to be the potential anti-allergy compounds that could bind with MRGPRX2. The binding affinity (K-D) of ROS and API with MRGPRX2 was (8.79 +/- 0.13) x 10(-8) m and (6.54 +/- 1.69) x 10(-8) m, respectively. The IC50 of API inhibiting laboratory of allergic disease 2 cells degranulation was also determined to be (51.96 +/- 0.18) mu m. Conclusions A MRGPRX2/CMC coupled with HPLC-ESI-IT-TOF system was successfully established and applied to discover the effective components from P. frutescens leaves.