Daphnetin Mitigates Ovalbumin-Induced Allergic Rhinitis in Mice by Regulating Nrf2/HO-1 and TLR4/NF-kB Signaling

Network pharmacology combined with experimental validation reveals the mechanism of action of cangerzisan on allergic rhinitis

ETHNOPHARMACOLOGICAL RELEVANCE

Allergic rhinitis (AR) stands as a non-infectious inflammatory condition affecting the nasal mucosa, marked by bouts of sneezing, nasal itching, and congestion. This ailment afflicts individuals across all age groups and poses challenges for effective treatment due to its chronic nature. Cangerzisan (CEZS), documented in the Jishengfang compendium, represents a traditional Chinese medicinal formula long utilized for AR management.

AIM OF THE STUDY

Investigating mechanism beneath therapeutic effect of CEZS in alleviating AR.

MATERIALS AND METHODS

The main active components in CEZS were determined by High Performance Liquid Chromatography (HPLC).The active constituents of CEZS and their corresponding targets were identified through an exhaustive screening process employing TCMSP database. To identify targets relevant to AR, GeneCards, OMIM, and DisGeNET databases were thoroughly applied. Protein-protein interaction (PPI) network was assembled utilizing STRING platform. Potential signaling pathways influenced by CEZS were delineated through GO and KEGG enrichment analyses. Subsequently, an AR model was induced by administering aluminum hydroxide (Al(OH)3) and ovalbumin (OVA) for affecting basal and local sensitization, respectively, facilitating experimental validation of the principal signaling pathways.

RESULTS

There were 61 active constituents identified within CEZS, targeting a pool of 129 entities associated with AR treatment. Pathways analysis of KEGG revealed that CEZS potentially inhibits AR advancement via modulating TLR4 signaling pathway. Animal experiments demonstrated that CEZS effectively alleviated symptom scores in guinea pigs with AR. Moreover, it exhibited notable improvements in serum immune and inflammatory factors levels, as well as reduced inflammatory infiltration within nasal mucosa, including goblet and mast cells. CEZS was found to enhance GATA-3 expression while reducing T-bet expression, thereby modulating the TH1/TH2 immune balance. Additionally, CEZS downregulated HMGB1, TLR4, and p-NF-κB/NF-κB protein expressions within nasal mucosa of guinea pigs.

CONCLUSIONS

The therapeutic mechanism of CEZS against AR involves rectifying TH1/TH2 immune imbalance and upregulating inflammatory and immune factors through modulating key proteins expression within TLR4 pathway. This targeted regulation effectively impedes AR progression.

New Insights into Mechanisms Traditional Chinese Medicine for Allergic Rhinitis by Regulating Inflammatory and Oxidative Stress Pathways

Allergy rhinitis (AR) is becoming more common and has serious medical and societal consequences. Sneezing, paroxysmal nasal blockage, nasal itching, mucosal edema, coughing, and rhinorrhea are symptoms of this type I allergic immunological illness. Immunoglobulin E-mediated inflammation is the cause of it. Because AR is prone to recurrent attacks, extended medication therapy may impair its effectiveness. In addition to negatively affecting the patients' physical health, this can also negatively impact their mental health. During AR development, there are inflammatory and oxidative stress responses that are linked to problems in a number of signal transduction pathways. By using the terms "allergic rhinitis", "traditional Chinese medicine", "inflammation", and "oxidative stress", we screened for pertinent research published over the previous five years in databases like PubMed. We saw that NF-KB, TLR, IL-33/ST2, PI3K/AKT, MAPK, and Nrf2 are some of the most important inflammatory and oxidative stress pathways in AR. Studies have revealed that antioxidant and anti-inflammatory therapy reduced the risk of AR and was therapeutic; however, the impact of the therapy varies widely. The Chinese medical system places a high value on traditional Chinese medicine (TCM), which has been there for virtually all of China's 5000-year history. By influencing signaling pathways related to inflammation and oxidative stress, Chinese herbal medicine and its constituent compounds have been shown to prevent allergic rhinitis. This review will focus on this evidence and provide references for clinical treatment and scientific research applications.

Inhibitory effect of daphnetin on the C48/80-induced pseudo-allergic reaction

Pseudo-allergic reaction is an allergic reaction mediated by nonimmunoglobulin E (IgE), which does not require prior contact with antigen sensitization and directly leads to mast cell degranulation. Daphnetin (DAP) is known for its anti-inflammatory effects, but there are few studies on the effect of DAP on pseudo-allergy and its mechanism. To investigate the effect of DAP on pseudo-allergy and its mechanism, we inflicted pseudo-allergy on RBL-2H3 cells using C48/80 in vitro. Moreover, to assess the antipseudo-allergy effect of C48/80 in vivo, mouse models of local anaphylaxis, systemic anaphylaxis, and itch were used. The in vitro results show that DAP inhibits degranulation and chemokine release; furthermore, DAP reduced the activation of the PLC-IP3R and MAPK signaling pathways induced by C48/80. Additionally, our in vivo results showed that DAP inhibited C48/80-induced local anaphylaxis and inhibited eosinophil aggregation, vasodilation and mast cell degranulation. In systemic anaphylaxis, DAP inhibits the decrease in body temperature and reduces the release of His, TNF-a and IL-8. In C48/80-induced itch, the number of scratches in mice was reduced. Our results demonstrate that DAP can play a suppressive role in the pseudo-allergy induced by C48/80, providing information for the cure of disorders linked to pseudo-allergic reactions.

Natural Coumarin Derivatives Activating Nrf2 Signaling Pathway as Lead Compounds for the Design and Synthesis of Intestinal Anti-Inflammatory Drugs

Nrf2 (nuclear factor erythroid 2-related factor 2) is a transcription factor related to stress response and cellular homeostasis that plays a key role in maintaining the redox system. The imbalance of the redox system is a triggering factor for the initiation and progression of non-communicable diseases (NCDs), including Inflammatory Bowel Disease (IBD). Nrf2 and its inhibitor Kelch-like ECH-associated protein 1 (Keap1) are the main regulators of oxidative stress and their activation has been recognized as a promising strategy for the treatment or prevention of several acute and chronic diseases. Moreover, activation of Nrf2/keap signaling pathway promotes inhibition of NF-κB, a transcriptional factor related to pro-inflammatory cytokines expression, synchronically promoting an anti-inflammatory response. Several natural coumarins have been reported as potent antioxidant and intestinal anti-inflammatory compounds, acting by different mechanisms, mainly as a modulator of Nrf2/keap signaling pathway. Based on in vivo and in vitro studies, this review focuses on the natural coumarins obtained from both plant products and fermentative processes of food plants by gut microbiota, which activate Nrf2/keap signaling pathway and produce intestinal anti-inflammatory activity. Although gut metabolites urolithin A and urolithin B as well as other plant-derived coumarins display intestinal anti-inflammatory activity modulating Nrf2 signaling pathway, in vitro and in vivo studies are necessary for better pharmacological characterization and evaluation of their potential as lead compounds. Esculetin, 4-methylesculetin, daphnetin, osthole, and imperatorin are the most promising coumarin derivatives as lead compounds for the design and synthesis of Nrf2 activators with intestinal anti-inflammatory activity. However, further structure-activity relationships studies with coumarin derivatives in experimental models of intestinal inflammation and subsequent clinical trials in health and disease volunteers are essential to determine the efficacy and safety in IBD patients.

Antiallergic Effects of Callerya atropurpurea Extract In Vitro and in an In Vivo Atopic Dermatitis Model

(1) Background: Callerya atropurpurea is found in Laos, Thailand, and Vietnam. Although the anti-inflammatory action of C. atropurpurea has been investigated, the functions of this plant in allergic responses are not understood. Here, we explored the antiallergic mechanism of C. atropurpurea ethanol extract (Ca-EE) using in vitro assays and an in vivo atopic model. (2) Methods: The constituents of Ca-EE were analyzed using GC/MS. Inhibition of lipoxygenase and β-hexosaminidase activity was examined, and the expression of inflammatory genes was measured by quantitative real-time PCR. The regulatory roles of Ca-EE in IgE/FcεRI signaling were examined by Western blotting. The DNCB-induced atopic dermatitis mouse model was performed with histological analysis. (3) Results: Ca-EE comprised cis-raphasatin, lupeol, some sugars, and fatty acids. In RBL-2H3 cells, treatment with Ca-EE significantly reduced the activities of lipoxygenase and β-hexosaminidase, as well as cytokine gene expression. IgE-mediated signaling was downregulated by blocking Lyn kinases. Moreover, Ca-EE effectively inhibited allergic symptoms in the DNCB-induced atopic dermatitis model without toxicity. (4) Conclusions: Ca-EE displayed antiallergic activities through regulating IgE/Lyn signaling in RBL-2H3 cells and a contact dermatitis model. These results indicate that Ca-EE could be effective for allergic disease treatment.