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.

Curcumin suppresses colorectal tumorigenesis via the Wnt/ß-catenin signaling pathway by downregulating Axin2.

Colorectal cancer (CRC) is the third most common cancer worldwide, with high incidence and mortality rates. Conventional therapies, including surgery, chemotherapy and radiation, are extensively used for the treatment of CRC. However, patients present with adverse effects, such as toxicity, hepatic injury and drug resistance. Thus, there is an urgent requirement to identify effective and safe therapy for CRC. Curcumin (CUR), a polyphenol substrate extracted from the rhizome of Curcuma longa, has been extensively studied for the treatment of CRC due to its high efficacy and fewer side effects. Previous studies have reported that several signaling pathways, such as NF-κB, Wnt/ß-catenin, are involved in the antitumor effects of CUR in vitro. However, the effect and mechanisms in vivo are not yet fully understood. The present study aimed to determine the molecular mechanism of colorectal cancer in vivo. Reverse transcription-quantitative PCR, western blot and immunohistochemistry analyses were performed to determine the underlying molecular mechanism of curcumin's anti-cancer effect in azoxymethane-dextran sodium sulfate induced colorectal cancer. The results of the present study demonstrated that CUR suppressed tumorigenesis in AOM-DSS induced CRC in mice, and anticancer effects were exerted by suppressing the expression of pro-inflammatory cytokines, and downregulating Axin2 in the Wnt/ß-catenin signaling pathway. Taken together, these results exhibit the potential in vivo mechanisms of the anticancer effects of CUR, and highlight Axin2 as a potential therapeutic target for CRC.

Rapid screening of bioactive compound in Sanzi Yangqin Decoction and investigating of binding mechanism by immobilized ß2-adrenogic receptor chromatography coupled with molecular docking.

Screening bioactive compounds from traditional Chinese medicines plays pivotal role in preventing and curing diseases. Sanzi Yangqin Decoction (SYD) is a commonly used prescription for the treatment of cough, asthma and some other respiratory diseases for hundreds of years in practice. This reminds us that there may exist some bioactive compounds strongly binding with the recognized receptors mediating these diseases like ß2-adrenegic receptor (ß2-AR). Therefore, this work intends to screen bioactive compounds from SYD and revealed the binding mechanism by immobilized ß2-AR chromatography and molecular docking. Taking advantages of a 3-high based enzymatic trans-methylation reaction (high speed, high specificity and high activity), the immobilization of ß2-AR was successfully achieved. Representative chromatographic peaks of SYD on the immobilized ß2-AR column was collected and recognized as rosmarinic acid and sinapine thiocyanate. Tension changes of the trachea ring showed that the two compounds were in a concentration-dependent manner when exerting their effects and the concentration ranges were 10-9-10-4 mol/L and 10-12-10-7 mol/L, respectively. Molecular docking revealed Ser203, Ser204, Ser207, Tyr316 and Asn312 were the main residues for the two compounds to bind with ß2-AR. We concluded that the proposed method is becoming an alternative in rapid recognizing bioactive compounds from complex matrix.

Immobilized angiotensin II type I receptor: A powerful method of high throughput screening for antihypertensive compound identification through binding interaction analysis.

The enormous growth in drug discovery paradigm has necessitated continuous exploration of new methods for drug-protein interaction analysis. To enhance the role of these methodologies in designing rational drugs, this work extended an immobilized angiotensin II type I receptor (AT1R) based affinity chromatography in antihypertensive compound identification. We fused haloalkane dehalogenase at C-terminus of AT1R and expressed the fusion receptor in E. coli. The expressed receptor was covalently immobilized onto 8.0 µm microspheres by mixing the cell lysate with 6-chlorocaproic acid-modified amino polystyrene microspheres. The immobilized AT1R was utilized for thermodynamic and kinetic interaction analysis between the receptor and four specific ligands. Following confirmation of these interactions by molecular docking, we identified puerarin and rosmarinic acid by determining their binding to the receptor. Azilsartan, candesartan, valsartan and olmesartan displayed two kinds of binding sites to AT1R by injection amount-dependent method. By molecular docking, we recognize the driving forces of the interaction as electrostatic interaction, hydrogen bonds and van der Waals force. The dissociation rate constants (kd) of azilsartan, candesartan, valsartan and olmesartan to AT1R were 0.01138 ± 0.003, 0.05142 ± 0.003, 0.07547 ± 0.004 and 0.01310 ± 0.005 min-1 by peak profiling assay. Comparing with these parameters, puerarin and rosmarinic acid presented lower affinity (KA: 0.12 × 104 and 1.5 × 104/M) and slower kinetics (kd: 0.6864 ± 0.03 and 0.3005 ± 0.01 min-1) to the receptor. These results, taking together, indicated that the immobilized AT1R has the capacity to probe antihypertensive compounds.