Antiasthmatic Compounds Targeting ß2-Adrenergic Receptor from Perilla frutescens Improved Lung Inflammation by Inhibiting the NF-κB Signaling Pathway.

Asthma is a highly prevalent and heterogeneous chronic respiratory disease and is often treated with inhaled corticosteroids or in combination with a ß2-adrenergic receptor (ß2-AR) agonist. However, around 5% of asthma remains uncontrolled, and more effective antiasthmatic drugs with known mechanisms are in high demand. Herein, we immobilized ß2-AR on the polystyrene amino microsphere surface in a one-step fashion. The successful immobilization of ß2-AR was verified by scanning electron microscopy and chromatographic analysis. We screened rosmarinic acid (RA) as the bioactive compound targeting ß2-AR in Perilla frutescens (L.) Britton by mass spectroscopy. The binding constant between RA and ß2-AR was determined to be 2.95 × 104 M-1 by adsorption energy distribution and frontal analysis. The antiasthmatic effect and mechanism of RA were examined on a murine model of allergic asthma induced by ovalbumin (OVA) and aluminum hydroxide. The results showed that RA significantly reduced lung inflammatory cell numbers, the production of Th2 cytokines, and the secretion of total IgE, OVA-specific IgE, and eotaxin. The decreased inflammatory cell infiltration and mucus hypersecretion were associated with the inhibition of the NF-κB signaling pathway. Moreover, the mRNA expression levels of AMCase, CCL11, CCR3, Ym2, and E-selectin in the lung tissues were effectively reduced. It is the first time that RA was proven to target ß2-AR and be effective in counteracting allergic airway inflammation via the NF-κB signaling pathway. Therefore, the immobilized ß2-AR preserves the potential in screening antiasthmatic compounds from herbal medicine, and RA can be developed as an effective agent for the treatment of allergic asthma.

Covalent immobilization of beta2 adrenergic receptor through trans-methylation reaction by SNAP-tag and its application in anti-asthmatic compound screening from Raphani Semen.

Beta2-adrenergic receptor (ß2-AR) is believed as an attractive target for anti-asthmatic drugs. Its crystal structure and pharmacological activity have been clearly investigated. Yet the number of the approved anti-asthmatic drugs has declined in recent years. This work reports on the preparation of an immobilized ß2-AR column through the specific trans-methylation reaction between SNAP tag and the benzyl-guanine derivative and application in anti-asthmatic compound screening from Raphani Semen. The characterization of the immobilized ß2-AR was performed by scanning electron microscopy (SEM) and receptor-ligand interaction analysis by chromatographic methods. SEM analysis showed that the receptor has been successfully coated on the surface of PEGA amino microspheres. Binding constants of salbutamol and terbutaline calculated from frontal analysis within the temperature range of 10-30 â„ƒ confirmed the feasibility of the method in a thermodynamic viewpoint. Hydrogen bond was verified as the main driving force for drug-receptor interaction analysis. Sinapine was identified as the potential bioactive compound in Raphani Semen that specifically bind with ß2-AR with a specific binding site of Ser 207. Taking together, the immobilized ß2-AR column is promising in exploring drug-protein interaction analysis and anti-asthmatic drug screening.