cimifugin and Asthma

Cimifugin is one of the main bioactive components of Yu-Ping-Feng-San, a well-known traditional Chinese medicine, which can effectively relieve Allergic asthma (AA) and atopic dermatitis and reduce recurrence in clinic. However, the underlying mechanism of cimifugin on AA is still unknown.. In the present study, we aimed to investigate the effect and mechanism of cimifugin on AA.. In vivo and in vitro experimental studies were performed.. The effect of cimifugin on AA was demonstrated in vivo and in vitro. Sepiapterin reductase (SPR) was predicted as the most potent target of cimifugin in treating AA by reverse docking. Molecular docking and microscale thermophoresis (MST) were used to analyze the direct binding between cimifugin and SPR. Overexpression and interference of SPR were performed to verify whether targeting SPR is a key step of cimifugin in the treatment of AA. QM385, an inhibitor of SPR, was administrated in vivo and in vitro to evaluate the role of SPR in AA. Further, HPLC and cell-free direct hSPR enzyme activity assay were performed to research whether cimifugin regulated SPR by influencing the enzyme activity. Simultaneously, the inhibitors of protein degradation were used in vitro to explore the mechanism of cimifugin on SPR.. We found cimifugin effectively alleviated AA by reducing airway hyperresponsiveness, inhibiting type 2 cytokines-mediated airway inflammation, and restoring the expression of epithelial barrier proteins. Molecular docking predicted the direct binding ability of cimifugin to SPR, which was further verified by MST. Notably, the therapeutic effect of cimifugin on AA was dampened with SPR interfering, in contrast, the phenotypic features of AA were significantly alleviated with QM385 application both in vivo and in vitro. Interestingly, cimifugin showed no effect on the enzyme activity of SPR, as the level of its substrate sepiapterin was not affected with cimifugin treatment by cell-free enzyme activity assay. Furthermore, we found cimifugin could reduce SPR protein expression without affecting its mRNA expression probably through autophagosome pathway.. To our knowledge, we're reporting for the first time that cimifugin can suppresses type 2 airway inflammation to alleviate AA by directly binding to SPR and regulating its protein expression in a non-enzymatic manner.

Topics: Asthma; Cytokines; Humans; Inflammation; Molecular Docking Simulation; Surface Plasmon Resonance

Long-term exposure to aeroallergens such as house dust mite (HDM) could result in airway inflammation and airway remodeling, characteristic features of allergic asthma. Huangqi-Fangfeng (HF), an important "couplet medicines" of Yu-Ping-Feng-San (YPFS), mediates allergen-induced airway inflammation in mice, but its role in the airway remodeling is not known.. To evaluate the effects of HF on airway remodeling of allergic asthma in a murine model and to investigate the underlying mechanisms in vivo and in vitro.. The main components of HF were analyzed by HPLC. The HDM-induced asthma mice model was established to study the effects of HF on airway inflammation and airway remodeling in vivo. Enhanced pause (Penh) index value was used as an indicator of airway hyper-reactivity. Bronchoalveolar lavage fluid (BALF) was processed for differential cell counting and determination of cytokines production. The lungs were fixed in 4% paraformaldehyde for histological examination after staining with H&E, trichrome and IHC. Production of interleukin (IL)-4, IL-5, IL-13, and transforming growth factor beta-1 (TGF-β1) in BALF and lung tissues, IgE in serum were measured by ELISAs. Expression of epithelial markers and mesenchymal markers were detected by immunohistochemistry and western blots. The effects of HF and its components on epithelial-mesenchymal transition (EMT) were detected in human bronchial epithelial cells (16HBE) treated with TGF-β1 and HDM.. The main components of Huangqi-Fangfeng detected by HPLC were Calycosin, Formononetin and Cimifugin. In HDM-induced allergic asthma mice model, respiratory exposure to HDM lead to airway hyperresponsiveness and thickening of the smooth muscle layer in the airway. TGF-β1 levels increased in mice airways while epithelial cells lost expression of E-cadherin and gained expression of the mesenchymal proteins N-cadherin, α-SMA and collagen І. These changes were relieved by treatment with HF. Furthermore, restored epithelial markers expression treated with individual components were also detectable in 16HBE cells.. These results demonstrated that Huangqi-Fangfeng protected against allergic airway remodeling through inhibiting epithelial-mesenchymal transition process in mice via regulating epithelial derived TGF-β1.

Topics: Airway Remodeling; Animals; Anti-Asthmatic Agents; Apiaceae; Asthma; Astragalus propinquus; Bronchi; Bronchoalveolar Lavage Fluid; Chromones; Disease Models, Animal; Drugs, Chinese Herbal; Epithelial Cells; Epithelial-Mesenchymal Transition; Humans; Isoflavones; Lung; Male; Mice, Inbred BALB C; Transforming Growth Factor beta1