Therapeutic potential of curcumin in experimentally induced allergic rhinitis in guinea pigs

Effectiveness of selective NaV1.7 blocker PF-05089771 in reducing cough associated with allergic rhinitis in guinea pigs

BACKGROUND

Allergic rhinitis (AR) is a common cause of chronic cough, linked to dysregulated airway C- and Aδ-fibres through inflammatory mediators. Despite the limited efficacy of current antitussive therapies, recent studies show that the NaV1.7 inhibitor can block cough in naïve guinea pigs. This study aimed to analyse the effect of the NaV1.7 blocker PF-05089771 on cough in guinea pigs with AR.

METHODS

Dunkin Hartley guinea pigs were sensitised and challenged with ovalbumin (OVA). Cough was induced using citric acid aerosol (0.4 M) before nasal challenge (NCH), and then one hour after the 1st, 3rd, and 6th NCH. The OVA-inhibitor group was pre-treated with inhaled NaV1.7 blocker (PF-05089771, 100 μM) before tussigen inhalation.

RESULTS

Chronic AR increased cough response to citric acid in both males and females. Pre-treatment with NaV1.7 blocker significantly inhibited cough reflex by ≈ 75 % in males and ≈ 80 % in females without affecting respiratory rate.

CONCLUSION

NaV1.7 blocker inhalation effectively inhibits cough in guinea pigs with AR.

Exploring Advances in Natural Plant Molecules for Allergic Rhinitis Immunomodulation in Vivo and in Vitro

Allergic rhinitis (AR) is a prevalent allergic disease that imposes significant economic burdens and life pressures on individuals, families, and society, particularly in the context of accelerating globalization and increasing pathogenic factors. Current clinical therapies for AR include antihistamines, glucocorticoids administered via various routes, leukotriene receptor antagonists, immunotherapy, and several decongestants. These treatments have demonstrated efficacy in alleviating clinical symptoms and pathological states. However, with the growing awareness of AR and rising expectations for improvements in quality of life, these treatments have become associated with a higher incidence of side effects and an elevated risk of drug resistance. Furthermore, the development of AR is intricately associated with dysregulation of the immune system, yet the underlying pathogenetic mechanisms remain incompletely understood. In contrast, widely available natural plant molecules offer multiple targeting pathways that uniquely modify the typical pathophysiology of AR through immunomodulatory processes. This review presents a comprehensive analysis of both in vivo and in vitro studies on natural plant molecules that modulate immunity for treating AR. Additionally, we examine their specific mechanisms of action in animal models to provide new insights for developing safe and effective targeted therapies while guiding experimental and clinical applications against AR.

Development of fast-dissolving sublingual nanofibers containing allergen and curcumin for immune response modulation in a mouse model of allergic rhinitis

Curcumin (CUR) has been considered a potential therapeutic agent for allergic reactions due to its antioxidant and anti-inflammatory activities. Nanofibers have attracted increasing attention in drug delivery. The aim of this study was to investigate the combined therapeutic effects of curcumin and allergen in nanofiber-based treatments in order to increase the effectiveness of sublingual immunotherapy (SLIT) efficacy in a mouse model of allergic rhinitis. Nanofibers containing CUR (1.25% and 2.5%) and ovalbumin 2% (OVA) as an allergen were prepared via electrospinning and characterized. BALB/c mice were sensitized with OVA to the induced allergic rhinitis model. SLIT with free and/or nanofibers was carried out. IL-4, INF-γ, and IgE serum levels were measured using ELISA. Splenocyte proliferation was evaluated by the MTT assay. Lung and nasal histological examinations and nasal lavage fluid (NALF) cell counting were carried out. Nanofibers containing 1.25% CUR and 2% OVA were chosen as the optimal formulations. SLIT treatment with the CUR and OVA nanofiber co-administration led to a significantly decreased serum IgE. Nanofiber containing 2.5 µg of CUR/mouse combined with OVA nanofiber showed a significant decrease in IL-4 and an increase in IFN-γ compared to other groups. NALF assessment showed a significant decrease in specific cell and eosinophil counts in the treated nanofiber groups. The histopathological results of NAL in the optimal formulations were near normal, with diminished cellular infiltration and inflammation. Our findings suggest that co-sublingual administration of allergen and CUR nanofibers can be considered as potential immunomodulatory agents.

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.

Curcumin does not significantly affect immediate skin tests

Background: Curcumin has been shown to decrease allergic symptoms and biomarkers in some animal and human studies. Objective: Our study aimed to determine if curcumin affects immediate skin-prick testing. Methods: We enrolled 34 participants sensitized to select antigens. The participants were randomized to treatment with curcumin or placebo in a double-blind fashion. The participants underwent titrated skin-prick testing before and after 1 week of treatment, and the pre- and posttreatment skin test wheals and flares were compared. Results: Curcumin did not have a statistically significant effect on immediate skin-prick test wheal or flare size. Conclusion: Although curcumin may attenuate allergic symptoms and biomarkers, it does not have a significant effect on immediate skin-prick test results and does not need to be discontinued before testing.

Curcuma longa and curcumin affect respiratory and allergic disorders, experimental and clinical evidence: A comprehensive and updated review

Curcuma longa and its constituents, mainly curcumin, showed various of pharmacological effects in previous studies. This review article provides updated and comprehensive experimental and clinical evidence regarding the effects of C. longa and curcumin on respiratory, allergic, and immunologic disorders. Using appropriate keywords, databases including PubMed, Science Direct, and Scopus were searched until the end of October 2021. C. longa extracts and its constituent, curcumin, showed the relaxant effect on tracheal smooth muscle, which indicates their bronchodilatory effect in obstructive pulmonary diseases. The preventive effects of extracts of C. longa and curcumin were shown in experimental animal models of different respiratory diseases through antioxidant, immunomodulatory, and anti-inflammatory mechanisms. C. longa and curcumin also showed preventive effects on some lung disorders in the clinical studies. It was shown that the effects of C. longa on pulmonary diseases were mainly due to its constituent, curcumin. Pharmacological effects of C. longa extracts and curcumin on respiratory, allergic, and immunologic disorders indicate the possible therapeutic effect of the plant and curcumin on these diseases.

The protective effect of Naringenin against ovalbumin-induced allergic rhinitis in rats

BACKGROUND

Allergic rhinitis (AR) is a ubiquitous chronic disease with a growing incidence. We aimed to investigate the protective effect of naringenin against AR induced in rats.

METHODS

Thirty-two Sprague Dawley rats were divided into four groups of eight animals each. Group 1 represented the control group. The other 24 rats were sensitized with intraperitoneal 0.3 mg ovalbumin (OVA) and 30 mg aluminum hydroxide every other day for 14 days to induce AR. Ten microliters OVA was administered to both nostrils by inhalation for the following seven days to provoke AR. Group 2 represented the AR group and received no treatment. Group 3 was treated as the reference group and received 5 mg/kg desloratadine every day between days 15 and 21. Group 4 received 100 mg/kg naringenin orally between days 15 and 21. All animal's sneezing and nasal itching scores were recorded on day 22. The rats were then sacrificed. Serum total IgE, IL4 and IL5 values were studied, and nasal structures were extracted 'en bloc' for histopathological examination.

RESULTS

Significant clinical recovery was achieved in the group treated with naringenin. Serum total IgE, IL4 and IL5 values in the naringenin group were significantly lower than in the AR group, and significant histopathological improvement was observed compared to the AR group.

CONCLUSIONS

Naringenin produced significant clinical, biochemical and histopathological benefits in rats with induced AR. These effects suggest that naringenin is a promising agent for the treatment of AR.

Immunomodulatory Effects of Curcumin in Rheumatoid Arthritis: Evidence from Molecular Mechanisms to Clinical Outcomes

Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disorder characterized by the destruction of the joint and bone resorption. The production of pro-inflammatory cytokines and chemokines, dysregulated functions of three important subtypes of T helper (TH) cells including TH1, TH17, and regulator T (Treg) cells are major causes of the initiation and development of RA. Moreover, B cells as a source of the production of several autoantibodies play key roles in the pathogenesis of RA. The last decades have seen increasingly rapid advances in the field of immunopharmacology using natural origin compounds for the management of various inflammatory diseases. Curcumin, a main active polyphenol compound isolated from turmeric, curcuma longa, possesses a wide range of pharmacologic properties for the treatment of several diseases. This review comprehensively will assess beneficial immunomodulatory effects of curcumin on the production of pro-inflammatory cytokines and also dysregulated functions of immune cells including TH1, TH17, Treg, and B cells in RA. We also seek the clinical efficacy of curcumin for the treatment of RA in several recent clinical trials. In conclusion, curcumin has been found to ameliorate RA complications through modulating inflammatory and autoreactive responses in immune cells and synovial fibroblast cells via inhibiting the expression or function of pro-inflammatory mediators, such as nuclear factor-κB (NF-κB), activated protein-1 (AP-1), and mitogen-activated protein kinases (MAPKs). Of note, curcumin treatment without any adverse effects can attenuate the clinical symptoms of RA patients and, therefore, has therapeutic potential for the treatment of the diseases.

Curcumin Ameliorates Ovalbumin-Induced Atopic Dermatitis and Blocks the Progression of Atopic March in Mice

Curcumin, extracted from the roots of Curcuma longa, has been used as an anti-inflammatory agent since the time of Ayurveda. The present work was designed to evaluate the potential of curcumin in amelioration of ovalbumin (OVA) induced AD in mice. Female BALB/c mice were subjected to skin OVA-patch application for a period of 1 week followed by resting period of 2 weeks, and the same protocol was repeated thrice. Curcumin was administered daily at dose of 20 mg/kg (i.p.) for 7 consecutive days during last sensitization phase. The phytochemical ameliorated the OVA-induced skin pathology as evident by normalization of epidermal thickness and suppressed infiltration of inflammatory cells in dermal region. The expression of Th2 promoting cytokines (TSLP/IL-33) and Th2 cytokines (IL-4/IL-5/IL-13/IL-31) was suppressed markedly along with reduced STAT-6 phosphorylation and GATA-3 expression. Curcumin administration also restored the redox balance and phosphorylation status of P65-NF-κB. Additionally, the epicutaneously sensitized mice challenged with aerosolized OVA developed asthmatic features which were effectively thwarted back upon curcumin treatment as reflected by data on total/differential cells in BALF and mRNA expression of Th2 cytokines in lungs. Overall, our findings demonstrate that curcumin treatment blunts the development of AD as well as associated atopic march in experimental mice.

Ethno-medicinal study of Artemisia ordosica Krasch. (traditional Chinese/Mongolian medicine) extracts for the treatment of allergic rhinitis and nasosinusitis

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia ordosica Krasch. (AOK) has been used for rheumatic arthritis, cold headache, sore throat, etc. in traditional Chinese/Mongolian medicine and is used for nasosinusitis by local Mongolian "barefoot" doctors. Up to now, their mechanisms are still unclear.

AIM

To evaluate the in vivo anti-inflammatory and allergic rhinitis (AR) alleviating effect as well as in vitro antimicrobial activities of AOK extracts to verify its ethno-medicinal claims.

MATERIALS AND METHODS

Crude extracts (methanol/95%-ethanol/ethyl acetate) of AOK root/stem/leaf and fractions (petroleum ether/ethyl acetate/n-butanol/aqueous) of AOK root extract were prepared. Xylene-induced ear swelling model in mouse and ovalbumin (OVA)-induced AR model in guinea pig were established. Ear swelling degrees of mice were measured. The numbers of rubbing movement and sneezes of guinea pigs were counted to evaluate the symptoms of AR. The serum levels of histamine, INF-γ, IL-2/4/10, and VCAM-1 were measured by ELISA assay. The histological changes of nasal mucosa were investigated by light microscope after H&E staining. Antimicrobial activities of AOK extracts were also tested. LC-MS/MS analysis was performed to characterize the constituents of active extract and molecular docking was conducted to predict the biological mechanism.

RESULTS

In ear-swelling model, extract (100.00 mg/kg) from the ethyl acetate layer of 95% ethanol (100.00 mg/kg) showed better swelling inhibition in mice than positive control (dexamethasone, 191.91 mg/kg). In AR model, extract from the ethyl acetate layer of 95% ethanol significantly alleviated the AR symptoms in guinea pigs, decreased the serum levels of histamine, INF-γ, IL-2/4/10, and VCAM-1, and reduced the infiltration of eosinophil in nasal mucosa. For Staphylococcus aureus, the ethyl acetate extract of AOK stem showed the highest inhibition (MIC=1.25 mg/mL), for Escherichia coli, n-butanol layer of 95% ethanol extract of AOK root showed the highest inhibition (MIC=15.00 mg/mL), for Candida glabrata, 95%-ethyl acetate extract of AOK leaf showed the best inhibition (MIC=0.064 mg/mL), while ethyl acetate and n-butanol layers showed similar inhibition on MRSA (MIC=7.50 mg/mL). LC-MS/MS characterization showed that dicaffeoylquinic acids account for more than 30% of ethyl acetate layer of AOK extract. Dicaffeoylquinic acids bind with histamine-1 receptor with high affinities and interesting modes.

CONCLUSIONS

Extracts from AOK had interesting anti-inflammatory activity in mice, alleviating effect against OVA-induced AR in guinea pigs, and antimicrobial activities in vitro, which support the ethno-medicinal use of it. The main constituents in ethyl acetate layer of AOK root extract are dicaffeoylquinic acids and could bind with histamine-1 receptor well. These findings highlighted the importance of natural product chemistry study of AOK.

Quantum chemical calculation and binding modes of H1R; a combined study of molecular docking and DFT for suggesting therapeutically potent H1R antagonist

Histamine-1 receptor (H1R) belongs to the family of rhodopsin-like G-protein-coupled receptors expressed in cells that mediates allergies and other pathophysiological diseases. For alleviation of allergic symptoms, H1R antagonists are therapeutic drugs; of which the most frequently prescribed are second generation drugs, such as; Cetirizine, Loratadine, Hydroxyzine, Desloratadine, Bepotastine, Acrivastine and Rupatadine. To understand their potency, binding affinity and interaction; we have employed molecular docking and quantum chemical study such as; Induced-fit docking and calculation of quantum chemical descriptors. This study also introduces the binding site characterization of H1R, with its known antagonists and Curcumin (our proposed alternative H1R antagonist); useful for future drug target site. The interactive binding site residues of H1R are found to be; Lys-191, Tyr-108, Asp-107, Tyr-100, Lys-179, Lys-191, Thr-194, Trp-428, Phe-432, Tyr-458, Hie-450, with most of these shown to be inhibited by naturally-occurring compound curcumin. Amongst the FDA approved drugs, Hydroxyzine showed best ligand binding affinity, calculated as - 141.491 kcal/mol and naturally occurring compound, Curcumin showed binding affinity of - 87.046 kcal/mol. The known antagonists of H1R has been used for hypothesizing curcumin as naturally occurring lead compound for the target using accurate molecular docking simulation study. Though the pharmacological action of known inhibitor is already established, they could differ from their reactivity, which we have also focused in our study for predicting drug reactivity.

Adipose Tissue-Derived Mesenchymal Stem Cell Modulates the Immune Response of Allergic Rhinitis in a Rat Model

This study was designed to investigate the potential effects and underlying mechanism of adipose tissue-derived mesenchymal stem cells (MSCs) on allergic inflammation compared to Montelukast as an antileukotriene drug in a rat model of allergic rhinitis (AR). The effect of MSCs was evaluated in albino rats that were randomly divided into four (control, AR, AR + Montelukast, and AR + MSCs) groups. Rats of AR group were sensitized by ovalbumin (OVA) and then challenged with daily nasal drops of OVA diluted in sterile physiological saline (50 μL/nostril, 100 mg/mL, 10% OVA) from day 15 to day 21 of treatment with/without Montelukast (1 h before each challenge) or MSCs I/P injection (1 × 10⁶ MCSs; weekly for three constitutive weeks). Both Montelukast and MSCs treatment started from day 15 of the experiment. At the end of the 5th week, blood samples were collected from all rats for immunological assays, histological, and molecular biology examinations. Both oral Montelukast and intraperitoneal injection of MSCs significantly reduced allergic symptoms and OVA-specific immunoglobulin E (IgE), IgG1, IgG2a and histamine as well as increasing prostaglandin E2 (PGE2). Further analysis revealed that induction of nasal innate cytokines, such as interleukin (IL)-4 and TNF-α; and chemokines, such as CCL11 and vascular cell adhesion molecule-1 (VCAM-1), were suppressed; and transforming growth factor-β (TGF-β) was up-regulated in Montelukast and MSCs-treated groups with superior effect to MSCs, which explained their underlying mechanism. In addition, the adipose tissue-derived MSCs-treated group had more restoring effects on nasal mucosa structure demonstrated by electron microscopical examination.

Inhibitory effects of bisdemethoxycurcumin on mast cell-mediated allergic diseases

Most allergic reactions are induced by mast cell activation. Mast cells play vital roles in the pathogenesis of allergic diseases. Bisdemethoxycurcumin (BDMC), a natural curcuminoid, has potential anti-allergic effects. Hence, we explored the effect of BDMC on mast cell-mediated allergic diseases. The study proved that BDMC suppresses β-hexosaminidase release, granule release, and membrane ruffling in monoclonal anti-2,4,6-dinitrophenyl-immunoglobulin (Ig) E/human serum albumin (DNP-IgE/HSA)-stimulated rat basophilic leukaemia cells (RBL-2H3 cells), and BDMC suppressed ovalbumin (OVA)-induced allergic rhinitis (AR) symptoms and OVA-specific IgE levels in AR mice. Furthermore, BDMC increased the survival of compound 48/80 anaphylaxis shock mice and elevated the decreased rectal temperature in OVA-induced active systemic anaphylaxis mice. These findings indicate that BDMC regulates the degranulation of mast cells, demonstrating its potential in the treatment of mast cell-induced allergic reactions.

Biyuanling suppresses the toluene-2, 4-diisocyanate induced allergic rhinitis in guinea pigs

Allergic rhinitis (AR), one of the common diseases of the upper respiratory system, is associated with high risk of nasopharyngeal carcinoma. Biyuanling Granules (BLG), a formulated preparation of traditional Chinese medicine, has been used in China for treatment of AR for more than a decade; however, its exact action against allergic rhinitis and the mechanism involved remain unclear. In this study, we studied the effects of BLG on allergic rhinitis induced by toluene-2, 4- diisocyanate (TDI) in guinea pigs. The anti-AR effects of BLG were evaluated by behavior observations, histological examinations of the nasal tissues stained with hematoxylin and eosin staining (H&E), immunohistochemical analyses of pulmonary surfactant associated protein (SP), Bcl-2 Associated X Protei (Bax), tumor necrosis factor (TNF-α) and vascular cell adhesion molecule-1 (VCAM-1) in the nasal mucosa, and serum tests of interleukin-4 (IL-4) and human SARS-specific immunoglobulin (SIgE) levels. We observed that in the AR-positive animals treated with BLG, the symptom scores were significantly higher (P < 0.01), the nasal mucosa edemas and inflammatory infiltrates were significantly alleviated (P < 0.01) and the serum IL-4 and SIgE levels were significantly decreased (P < 0.05) as compared with the control group. Immunohistochemical examinations of the nasal mucosa demonstrated that the expressions of TNF-α, SP and VCAM-1 were significantly decreased (P < 0.01), whereas Bax expression was increased in the BLG treatment groups (P < 0.05). These results indicate that BLG can effectively suppress the TDI-induced AR, and that the protective effects of BLG were associated with reductions of TNF-α, SP and VCAM-1, and an elevation of Bax, suggesting that BLG exerts its AR-suppressive effects through inhibition of inflammatory response.

Can curcumin modulate allergic rhinitis in rats?

OBJECTIVES

This study aimed to explore the effects of curcumin on experimental allergic rhinitis in rats.

METHODS

Twenty-eight male Wistar albino rats were randomly divided into four groups: a control group; a group in which allergic rhinitis was induced and no treatment given; a group in which allergic rhinitis was induced followed by treatment with azelastine hydrochloride on days 21-28; and a group in which allergic rhinitis was induced followed by treatment with curcumin on days 21-28. Allergy symptoms and histopathological features of the nasal mucosa were examined.

RESULTS

The sneezing and nasal congestion scores were higher in the azelastine and curcumin treatment groups than in the control group. Histopathological examination showed focal goblet cell metaplasia on the epithelial surface in the azelastine group. In the curcumin group, there was a decrease in goblet cell metaplasia in the epithelium, decreased inflammatory cell infiltration and vascular proliferation in the lamina propria.

CONCLUSION

Curcumin is an effective treatment for experimentally induced allergic rhinitis in rats.

Effect of curcumin on nasal symptoms and airflow in patients with perennial allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) is a common disorder that can significantly affect patient quality of life. Previous studies have found that curcumin had anti-inflammatory and antioxidant effects and clinical benefits in cancer and asthma.

OBJECTIVE

To determine the efficacy of curcumin in the treatment of AR and to explore the molecular mechanisms involved.

METHODS

In a randomized, double-blind study, 241 patients with AR received either placebo or oral curcumin for 2 months. The therapeutic effects of curcumin were evaluated by nasal symptoms and nasal airflow resistance. In addition, the production of interferon γ, interleukin (IL) 4, IL-10, and tumor necrosis factor α from mononuclear cells and IL-8, soluble intercellular adhesion molecule, polyethylene glycol 2, and leukotriene C4 from polymorphonuclear neutrophils were compared before and after curcumin treatment.

RESULTS

Curcumin alleviated nasal symptoms (sneezing and rhinorrhea) and nasal congestion through reduction of nasal airflow resistance. Curcumin was found to exert diverse immunomodulatory effects, including suppression of IL-4, IL-8, and tumor necrosis factor α and increased production of IL-10 and soluble intercellular adhesion molecule. However, curcumin did not affect the release of prostaglandin E2 and leukotriene C4 from polymorphonuclear neutrophils.

CONCLUSION

This pilot study provides the first evidence of the capability of curcumin of improving nasal airflow and modulating immune response in patients with AR.

Antioxidant activities of curcumin in allergic rhinitis

We investigated the antioxidant effects of curcumin in an experimental rat model of allergic rhinitis (AR). Female Wistar albino rats (n = 34) were divided randomly into four groups: healthy rats (control group, n = 8), AR with no treatment (AR + NoTr group, n = 10), AR with azelastine HCl treatment (AR + Aze group, n = 8), and AR with curcumin treatment (AR + Curc group, n = 8). On day 28, total blood IgE levels were measured. For measurement of antioxidant activity, the glutathione (GSH) level and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured in both inferior turbinate tissue and serum. Malondialdehyde (MDA) levels were measured only in inferior turbinate tissue, and paraoxonase (PON) and arylesterase (ARE) activities were measured only in serum. Statistically significant differences were found for all antioxidant measurements (GSH levels and CAT, SOD, GSH-Px activities in the serum and tissue, MDA levels in the tissue, and PON and ARE activities in the serum) between the four groups. In the curcumin group, serum SOD, ARE, and PON and tissue GSH values were higher than the control group. Moreover, tissue GSH levels and serum GSH-Px activities in the curcumin group were higher than in the AR + NoTr group. In the azelastine group, except MDA, antioxidant measurement values were lower than in the other groups. Curcumin may help to increase antioxidant enzymes and decrease oxidative stress in allergic rhinitis. We recommend curcumin to decrease oxidative stress in allergic rhinitis.

Cinnamaldehyde is an effective anti-inflammatory agent for treatment of allergic rhinitis in a rat model

OBJECTIVES

The effect of cinnamaldehyde on the treatment of allergic rhinitis (AR) was investigated in rat model.

METHODS

Twenty-eight female Wistar albino rats were randomly divided into four groups: Group 1 (control) (C), Group 2 (AR with no treatment) (AR+NoTr), Group 3 (AR+Azelastine HCl) (AR+Aze), and Group 4 (AR+cinnamaldehyde) (AR+Cin). At day 21, AR+Aze rats were given an Azelastine HCl drop, and AR+Cin rats were given cinnamaldehyde intranasally. In all groups, allergic symptoms histopathological results were evaluated.

RESULTS

The AR+NoTr group showed the worst allergic symptoms, cilia loss and greater inflammation. In the AR+Aze and AR+Cin groups, allergic symptom scores were higher than those in the control group. However, between AR+Aze and AR+Cin groups, there were no significant differences in the allergic symptom scores Histopathological analysis revealed vascular congestion and an increase in goblet cell numbers in the AR+Cin group. However, AR+Cin rat nasal mucosa had less plasma cell infiltration compared with the AR+NoTr group. In rats from the AR+Aze group, analysis of the nasal mucosa revealed less eosinophil infiltration than that seen in the AR+NoTr group. A lower score for mast cell (MC) infiltration was observed in the nasal mucosa of rats treated with Azelastine HCl compared with cinnamaldehyde.

CONCLUSIONS

In this study we observed that both Azelastine HCl and cinnamaldehyde reduced allergic symptoms in an AR rat model. Cinnamaldehyde decreased vascular congestion as well as plasma cell, eosinophil, and inflammatory cell infiltration into the lamina propria.

Anti-Interleukin-1 Beta/Tumor Necrosis Factor-Alpha IgY Antibodies Reduce Pathological Allergic Responses in Guinea Pigs with Allergic Rhinitis

This study aims to determine whether the combined blockade of IL-1β and TNF-α can alleviate the pathological allergic inflammatory reaction in the nasal mucosa and lung tissues in allergic rhinitis (AR) guinea pigs. Healthy guinea pigs treated with saline were used as the healthy controls. The AR guinea pigs were randomly divided into (1) the AR model group treated with intranasal saline; (2) the 0.1% nonspecific IgY treatment group; (3) the 0.1% anti-TNF-α IgY treatment group; (4) the 0.1% anti-IL-1β IgY treatment group; (5) the 0.1% combined anti-IL-1β and TNF-α IgY treatment group; and (6) the fluticasone propionate treatment group. The inflammatory cells were evaluated using Wright's staining. Histopathology was examined using hematoxylin-eosin staining. The results showed that the number of eosinophils was significantly decreased in the peripheral blood, nasal lavage fluid, and bronchoalveolar lavage fluid (P < 0.05), and eosinophil, neutrophil, and lymphocyte infiltration and edema were significantly reduced or absent in the nasal mucosa and lung tissues (P < 0.05) in the combined 0.1% anti-IL-1β- and TNF-α IgY-treated guinea pigs. The data suggest that topical blockade of IL-1β and TNF-α could reduce pathological allergic inflammation in the nasal mucosa and lung tissues in AR guinea pigs.

Turmeric (Curcuma longa) attenuates food allergy symptoms by regulating type 1/type 2 helper T cells (Th1/Th2) balance in a mouse model of food allergy

ETHNOPHARMACOLOGICAL RELEVANCE

Turmeric (Curcuma longa) has traditionally been used to treat pain, fever, allergic and inflammatory diseases such as bronchitis, arthritis, and dermatitis. In particular, turmeric and its active component, curcumin, were effective in ameliorating immune disorders including allergies. However, the effects of turmeric and curcumin have not yet been tested on food allergies.

MATERIALS AND METHODS

Mice were immunized with intraperitoneal ovalbumin (OVA) and alum. The mice were orally challenged with 50mg OVA, and treated with turmeric extract (100mg/kg), curcumin (3mg/kg or 30 mg/kg) for 16 days. Food allergy symptoms including decreased rectal temperature, diarrhea, and anaphylaxis were evaluated. In addition, cytokines, immunoglobulins, and mouse mast cell protease-1 (mMCP-1) were evaluated using ELISA.

RESULTS

Turmeric significantly attenuated food allergy symptoms (decreased rectal temperature and anaphylactic response) induced by OVA, but curcumin showed weak improvement. Turmeric also inhibited IgE, IgG1, and mMCP-1 levels increased by OVA. Turmeric reduced type 2 helper cell (Th2)-related cytokines and enhanced a Th1-related cytokine. Turmeric ameliorated OVA-induced food allergy by maintaining Th1/Th2 balance. Furthermore, turmeric was confirmed anti-allergic effect through promoting Th1 responses on Th2-dominant immune responses in immunized mice.

CONCLUSION

Turmeric significantly ameliorated food allergic symptoms in a mouse model of food allergy. The turmeric as an anti-allergic agent showed immune regulatory effects through maintaining Th1/Th2 immune balance, whereas curcumin appeared immune suppressive effects. Therefore, we suggest that administration of turmeric including various components may be useful to ameliorate Th2-mediated allergic disorders such as food allergy, atopic dermatitis, and asthma.

Anti-inflammatory effect of curcumin on mast cell-mediated allergic responses in ovalbumin-induced allergic rhinitis mouse

Curcumin has commonly been used for the treatment of various allergic diseases. However, its precise anti-allergic rhinitis effect and mechanism remain unknown. In the present study, the effect of curcumin on allergic responses in ovalbumin (OVA)-induced allergic rhinitis mouse was investigated. We explored the effect of curcumin on the release of allergic inflammatory mediators, such as histamine, OVA-specific IgE, and inflammatory cytokines. Also, we found that curcumin improved rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and decreased the serum levels of histamine, OVA-specific IgE and TNF-α in OVA-induced allergic rhinitis mice. In addition, curcumin suppressed the production of inflammatory cytokines, such as TNF-α, IL-1β, IL-6 and IL-8. Moreover, curcumin significantly inhibited PMA-induced p-ERK, p-p38, p-JNK, p-Iκ-Bα and NF-κB. These findings suggest that curcumin has an anti-allergic effect through modulating mast cell-mediated allergic responses in allergic rhinitis, at least partly by inhibiting MAPK/NF-κB pathway.

Ca2+ -activated K+ channel-3.1 blocker TRAM-34 alleviates murine allergic rhinitis

The precise pathogenesis of allergic rhinitis (AR) remains unclear and AR is less easily cured. Recent evidence has suggested that calcium-activated K+ channel-3.1(KCa3.1) is implicated in the immune response of allergic and inflammatory diseases and TRAM-34 is a selective KCa3.1 blocker. However, little is known about its role in AR. We aimed to investigate the effect of TRAM-34 in a mouse model of AR induced by ovalbumin (OVA). The BALB/c mice were divided into six groups: untreated AR group, 200 μg TRAM-34 treated AR group, 400 μg TRAM-34 treated AR group, 200 μg TRAM-34 treated normal group, 400 μg TRAM-34 treated normal group and untreated normal control group. Histopathological characteristics were assessed by HE staining. KCa3.1 protein expression was investigated by immunohistochemistry and western blotting method, and mRNA expression of KCa3.1, stromal interaction molecule1 (STIM1) and Orai1 in nasal tissues were assessed by real-time PCR. Furthermore, concentrations of OVA-specific IgE, ECP, IL-4, IL-5, IL-17 and IL-1β in nasal lavage fluid (NLF) were analyzed by enzyme-linked immunosorbent assay (ELISA). Results showed that TRAM-34 administration into the nostril attenuated sneezing, nasal rubbing, epithelial cell proliferation, eosinophil infiltration and inhibited nasal mucosa KCa3.1, STIM1 and Orai1 expression in TRAM-34 treated mice compared with untreated AR mice and suppressed inflammatory cytokines in the NLF of TRAM-34 treated groups compared with untreated AR mice. In conclusion, TRAM-34 could effectively alleviate murine allergic rhinitis by suppressing KCa3.1 and leads to reduction of K+ efflux and Ca2 + influx, leading to inflammation reduction and allergic responses attenuation.

Curcumin Ingestion Inhibits Mastocytosis and Suppresses Intestinal Anaphylaxis in a Murine Model of Food Allergy

IgE antibodies and mast cells play critical roles in the establishment of allergic responses to food antigens. Curcumin, the active ingredient of the curry spice turmeric, has anti-inflammatory properties, and thus may have the capacity to regulate Th2 cells and mucosal mast cell function during allergic responses. We assessed whether curcumin ingestion during oral allergen exposure can modulate the development of food allergy using a murine model of ovalbumin (OVA)-induced intestinal anaphylaxis. Herein, we demonstrate that frequent ingestion of curcumin during oral OVA exposure inhibits the development of mastocytosis and intestinal anaphylaxis in OVA-challenged allergic mice. Intragastric (i.g.) exposure to OVA in sensitized BALB/c mice induced a robust IgE-mediated response accompanied by enhanced OVA-IgE levels, intestinal mastocytosis, elevated serum mMCP-1, and acute diarrhea. In contrast, mice exposed to oral curcumin throughout the experimental regimen appeared to be normal and did not exhibit intense allergic diarrhea or a significant enhancement of OVA-IgE and intestinal mast cell expansion and activation. Furthermore, allergic diarrhea, mast cell activation and expansion, and Th2 responses were also suppressed in mice exposed to curcumin during the OVA-challenge phase alone, despite the presence of elevated levels of OVA-IgE, suggesting that curcumin may have a direct suppressive effect on intestinal mast cell activation and reverse food allergy symptoms in allergen-sensitized individuals. This was confirmed by observations that curcumin attenuated the expansion of both adoptively transferred bone marrow-derived mast cells (BMMCs), and inhibited their survival and activation during cell culture. Finally, the suppression of intestinal anaphylaxis by curcumin was directly linked with the inhibition of NF-κB activation in curcumin-treated allergic mice, and curcumin inhibited the phosphorylation of the p65 subunit of NF-κB in BMMCs. In summary, our data demonstrates a protective role for curcumin during allergic responses to food antigens, suggesting that frequent ingestion of this spice may modulate the outcome of disease in susceptible individuals.

Curcumin, inflammation, and chronic diseases: how are they linked?

It is extensively verified that continued oxidative stress and oxidative damage may lead to chronic inflammation, which in turn can mediate most chronic diseases including cancer, diabetes, cardiovascular, neurological, inflammatory bowel disease and pulmonary diseases. Curcumin, a yellow coloring agent extracted from turmeric, shows strong anti-oxidative and anti-inflammatory activities when used as a remedy for the prevention and treatment of chronic diseases. How oxidative stress activates inflammatory pathways leading to the progression of chronic diseases is the focus of this review. Thus, research to date suggests that chronic inflammation, oxidative stress, and most chronic diseases are closely linked, and the antioxidant properties of curcumin can play a key role in the prevention and treatment of chronic inflammation diseases.

Therapeutic potential of combined anti-IL-1β IgY and anti-TNF-α IgY in guinea pigs with allergic rhinitis induced by ovalbumin

We have previously demonstrated that anti-IL-1β immunoglobulin yolk(IgY) inhibits pathological responses in allergic asthma guinea pigs induced by ovalbumin(OVA). This study aims to determine whether the combined blockade of IL-1β and TNF-α can more effectively inhibit allergic inflammation in allergic rhinitis(AR) guinea pigs induced by OVA. Healthy guinea pigs treated with saline were used as the healthy control. The AR guinea pigs induced by OVA were randomly divided into (1) the AR model group containing negative control animals treated with intranasal saline; (2) the 0.1% non-specific IgY treatment group treated with non-specific IgY; (3) the 0.1% anti-TNF-α IgY treatment group treated with 0.1% anti-TNF-α IgY; (4) the 0.1% anti-IL-1β IgY treatment group treated with 0.1% anti-IL-1β IgY; (5) the 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY treatment group treated with 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY; and (6) the fluticasone propionate treatment group treated with fluticasone propionate. Cytokines were measured using an enzyme-linked immunosorbent assay. The results showed that IL-1β, IL-5, IL-9, IL-13, IL-18, IL-22, IL-33, TNF-α, TGF-β1 and OVA-specific IgE levels in the peripheral blood (PB) and nasal lavage fluid (NLF) significantly decreased at 2h, 4h or 8h in the 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY treatment group compared to the AR model group and the 0.1% non-specific IgY treatment group (P<0.05). The data suggest that blockade of IL-1β and TNF-α by intranasal instillation of combined anti-IL-1β IgY and anti-TNF-α IgY could be a potential alternative strategy for preventing and treating allergic rhinitis.

Synthesis and evaluation of a series of novel asymmetrical curcumin analogs for the treatment of inflammation

Curcumin has been reported to possess multiple bioactivities, such as antioxidant, anticancer, and anti-inflammatory properties, however the clinical application of curcumin has been significantly limited by its instability and poor metabolism. Modification of curcumin has led to discovery and development of lots of novel therapeutic candidates. In recent years acute and chronic inflammation has been the focus of numerous studies in various diseases. Here, we synthesized a series of asymmetrical curcumin analogs with high in vitro chemical stability, and their anti-inflammatory activity was evaluated in LPS-stimulated macrophages. According to the bio-screening results and QSAR analysis, these analogs exhibited potent activities against LPS-induced TNF-α and IL-6 release. Among the analogs of the potent anti-inflammatory activity, compounds 3b8 and 3b9 exhibited significant protection and possess enhanced anti-inflammatory activity thereby attenuated the LPS-induced septic death in mice.