Rosae multiflorae Fructus Extract Improves Trimellitic Anhydride-Induced Atopic Dermatitis-Like Symptoms.

Allergic disorders, including atopic dermatitis (AD), are closely linked to the activation of type 2 helper T (Th2) cells. The aim of this study was to investigate the possibility of using Rosae multiflorae fructus extract (RMFE) for AD treatment in the AD-like mouse model induced by treatment with trimellitic anhydride (TMA). Oral treatment of RMFE reduced the increase in ear thickness and suppressed inflammatory cytokine expression (interleukin [IL]-1ß and tumor necrosis factor [TNF]-α) and Th2-associated immune responses (immunoglobulin [Ig] E and IL-4) in mouse ears. Furthermore, messenger RNA (mRNA) expression levels such as IL-4, IL-5, and IL-13, in draining lymph nodes were decreased by RMFE. Furthermore, we found that RMFE increased the level of heme oxygenase-1 (HO-1) through ERK and p38 pathways, reducing IL-2 production and CD4+ T cell proliferation, and inhibited STAT6 phosphorylation. Therefore, this study suggested that RMFE could be an effective treatment of AD induced by Th2-mediated immune responses by suppressing proliferation of CD4+ T cells via increased HO-1.

Piperine Ameliorates Trimellitic Anhydride-Induced Atopic Dermatitis-Like Symptoms by Suppressing Th2-Mediated Immune Responses via Inhibition of STAT6 Phosphorylation.

Atopic dermatitis (AD) is a common inflammatory skin disease predominately related to Type 2 helper T (Th2) immune responses. In this study, we investigated whether piperine is able to improve AD symptoms using a trimellitic anhydride (TMA)-induced AD-like mouse model. Topical treatment with piperine reduced ear swelling (ear thickness and epidermal thickness) induced by TMA exposure. Furthermore, piperine inhibited pro-inflammatory cytokines such as TNF-α and IL-1ß in mouse ears, compared with the TMA-induced AD group. In measuring allergic immune responses in draining lymph nodes (dLNs), we found that IL-4 secretion, GATA3 mRNA level, and STAT6 phosphorylation were suppressed by piperine treatment. In an ex vivo study, piperine also inhibited the phosphorylation of STAT6 on the CD4+ T cells isolated from splenocytes of BALB/c mice, and piperine suppressed IL-4-induced CCL26 mRNA expression and STAT6 phosphorylation in human keratinocytes resulting in the inhibition of infiltration of CCR3+ cells into inflammatory lesions. These results demonstrate that piperine could ameliorate AD symptoms through suppression of Th2-mediated immune responses, including the STAT6/GATA3/IL-4 signaling pathway. Therefore, we suggest that piperine is an excellent candidate as an inhibitor of STAT6 and may help to improve AD symptoms.

Silkworm dropping extract regulates food allergy symptoms via inhibition of Th2-related responses in an ovalbumin-induced food allergy model.

BACKGROUND: Silkworm droppings have long been used in traditional medicine to remedy allergic itching, palsy, blood circulation problems, and arthritis in Asian countries. To investigate the anti-allergic effect of silkworm dropping extract (SDE) and its mechanism, we used a mouse model of food allergy induced by ovalbumin (OVA). RESULTS: SDE ameliorated the symptoms of OVA-induced food allergies, and the levels of T helper 2 (Th2)-related cytokines [such as interleukin (IL)-4, IL-5, IL-10, and IL-13] were found to be significantly decreased in both the spleen and mesenteric lymph nodes by SDE. Furthermore, SDE treatment directly inhibited OVA permeation, IL-4 production, and degranulation of mast cells; in contrast, immunoglobulin E (IgE) production from B cells was not affected. CONCLUSION: These results suggest that SDE has potential anti-allergic activities, and SDE may be useful in the treatment/prevention of allergic disorders such as food allergies, serving as therapeutic agents. © 2019 Society of Chemical Industry.

Rosae multiflorae fructus extract and its four active components alleviate ovalbumin-induced allergic inflammatory responses via regulation of Th1/Th2 imbalance in BALB/c rhinitis mice.

BACKGROUND: Rosae Multiflorae fructus has potent antioxidative, analgesic, and anti-inflammatory properties. PURPOSE: We investigated the immunomodulatory effect of Rosae Multiflorae fructus extract (RMFE) on allergic inflammation in an allergic rhinitis (AR) mouse model. METHODS: Mice were sensitized and intranasally challenged with ovalbumin (OVA), the Th1/Th2-related cytokines and histopathology were examinated after RMFE treatments. Primary cell culture from spleen and NALT was performed to evaluate RMFE effect on Th1/Th2 responses. Four active components of RMFE were determined using HPLC and then tested the inhibition on Th2 response. RESULTS: Oral administration of RMFE inhibited the accumulation of eosinophils in nasal lavage fluid (NALF) and the nasal mucosa, goblet cells in the nasal epithelium, and mast cells in the respiratory region of the nasal cavity. Thus, the swelling of the nasal epithelium, nasal-associated lymphoid tissue (NALT), and lung tissue were ameliorated. Furthermore, the RMFE suppressed Th2-related cytokines, such as IL-4, IL-5, and IL-13 in NALF, NALT, and splenocytes, whereas the Th1-associated cytokine IL-12 was up-regulated by RMFE. We also revealed the active components of RMFE, such as ellagic acid, hyperoside, isoquercitrin, and miquelianin. They may inhibit IL-4 secretion in allergic responses. CONCLUSION: RMFE may have therapeutic potential for treating AR by modulating the relationships between Th1/Th2 responses.

Silkworm dropping extract ameliorate trimellitic anhydride-induced allergic contact dermatitis by regulating Th1/Th2 immune response.

Allergic contact dermatitis (ACD) is an inflammatory skin disease caused by hapten-specific immune response. Silkworm droppings are known to exert beneficial effects during the treatment of inflammatory diseases. Here, we studied whether topical treatment and oral administration of silkworm dropping extract (SDE) ameliorate trimellitic anhydride (TMA)-induced ACD. In ACD mice model, SDE treatment significantly suppressed the increase in both ear thickness and serum IgE levels. Furthermore, IL-1ß and TNF-α levels were reduced by SDE. In allergic responses, SDE treatment significantly attenuated the production of the Th2-associated cytokine IL-4 in both ear tissue and draining lymph nodes. However, it increased the production of the Th1-mediated cytokine IL-12. Thus, these results showed that SDE attenuated TMA-induced ACD symptoms through regulation of Th1/Th2 immune response. Taken together, we suggest that SDE treatment might be a potential agent in the prevention or therapy of Th2-mediated inflammatory skin diseases such as ACD and atopic dermatitis. ABBREVIATIONS: ACD: allergic contact dermatitis; AD: atopic dermatitis; APC: antigen presenting cells; CCL: chemokine (C-C motif) ligand; CCR: C-C chemokine receptor; Dex: dexamethasone; ELISA: enzyme-linked immunosorbent assay; IFN: interferon; Ig: immunoglobulin; IL: interleukin; OVA: ovalbumin; PS: prednisolone; SDE: silkworm dropping extract; Th: T helper; TMA: trimellitic anhydride; TNF: tumor necrosis factor.

Skullcap (Scutellaria Baicalensis) Hexane Fraction Inhibits the Permeation of Ovalbumin and Regulates Th1/2 Immune Responses.

Skullcap (Scutellaria baicalensis) is well known for its anti-inflammatory and anti-allergic effects. In our previous study, we found that skullcap could inhibit allergen permeation and regulate Th1/2 immune balance. To reveal the key fractions and components of skullcap, we fractionated skullcap extract into five fractions: hexane, chloroform, ethyl acetate, butanol, and water fraction. Among these fractions, the hexane fraction significantly suppressed the production of Th2-mediated cytokines (Interleukin (IL)-4, 5, 10 and 13) and increased Th1-mediated cytokines (Interferon (IFN)-γ and IL-12). Furthermore, the hexane fraction inhibited the permeation of ovalbumin (OVA), used as an allergen, across the intestinal epithelial cell monolayer. To confirm the active compounds in the hexane fraction, fatty acids were analyzed. Linoleic acid (LA, C18:2 (>59.7%)) was identified as the most important fatty acid in the skullcap hexane fraction. LA significantly suppressed IL-4 production and increased IFN-γ secretion, as well as inhibiting OVA permeation. Thus, LA significantly diminished the permeation of allergen by enhancing intestinal barrier function and regulated allergic responses to maintain Th1/Th2 immune balance.

Piper nigrum extract ameliorated allergic inflammation through inhibiting Th2/Th17 responses and mast cells activation.

Piper nigrum (Piperaceae) is commonly used as a spice and traditional medicine in many countries. P. nigrum has been reported to have anti-oxidant, anti-bacterial, anti-tumor, anti-mutagenic, anti-diabetic, and anti-inflammatory properties. However, the effect of P. nigrum on allergic asthma has not been known. This study investigated the effect of P. nigrum ethanol extracts (PNE) on airway inflammation in asthmatic mice model. In the ovalbumin (OVA)-induced allergic asthma model, we analysed the number of inflammatory cells and cytokines production in bronchoalveolar lavage fluid (BALF) and lung tissue; histological structure; as well as the total immunoglobulin (Ig)E, anti-OVA IgE, anti-OVA IgG1 and histamine levels in serum. The oral administration (200 mg/kg) of PNE reduced the accumulation of inflammatory cells (eosinophils, neutrophils in BALF and mast cells in lung tissue); regulated the balance of the cytokines production of Th1, Th2, Th17 and Treg cells, specifically, inhibited the expressions of GATA3, IL-4, IL-6, IL-1ß, RORγt, IL-17A, TNF-α and increased the secretions of IL-10, INF-γ in BALF and lung homogenate. Moreover, PNE suppressed the levels of total IgE, anti-OVA IgE, anti-OVA IgG1 and histamine release in serum. The histological analysis showed that the fibrosis and infiltration of inflammatory cells were also ameliorated in PNE treated mice. On the other hand, PNE inhibited the allergic responses via inactivation of rat peritoneal mast cells degranulation. These results suggest that PNE has therapeutic potential for treating allergic asthma through inhibiting Th2/Th17 responses and mast cells activation.

Trigonella foenum-graecum alleviates airway inflammation of allergic asthma in ovalbumin-induced mouse model.

Trigonella foenum-graecum, a member oldest medicinal plant in the fabaceae (legumes) family, is used as a herb, spice, and vegetable, and known for its olfactory, laxative, and galactogogue effects. However, the inhibitory effect of Trigonella foenum-graecum on allergic inflammatory response remains unclear, therefore, we investigated the precise role of Trigonella foenum-graecum in the allergic asthma and revealed the effects of Trigonella foenum-graecum in regulating airway inflammation and its possible mechanism. Allergic asthma was initiated in BALB/c mice by sensitized with OVA emulsified in aluminum on days 1 and 14, then aerosol challenged with OVA on days 27, 28 and 29. Some mice were administered Trigonella foenum-graecum by oral gavage before challenge. Then mice were evaluated for the presence of airway inflammation, production of allergen-specific cytokine response and lung pathology. Trigonella foenum-graecum significantly ameliorated the number of inflammatory cells in BALF and alleviated lung inflammation. It also reduced the collagen deposition and goblet cells. Meanwhile, Trigonella foenum-graecum treatment evidently decreased the high expression of Th2 cytokines and increased the Th1 cytokines in BALF and lung homogenates. Trigonella foenum-graecum showed a significant inhibition of serum IgE and anti-OVA IgG1. In this study, our data suggest that Trigonella foenum-graecum has a significant anti-inflammatory effect and it may prove to be an efficacious therapeutic regent on allergic asthma.

Effect of acid treatment on allergenicity of peanut and egg.

BACKGROUND: Many food experts have studied various treatments or processing techniques in order to develop hypoallergenic foods. In a previous study, acid treatment dramatically mitigated the allergenicity of peanut, especially Ara h 2. RESULTS: Gel electrophoresis showed that most protein bands of acid-treated peanut were not detected, but protein bands of egg white became weaker and broader by acid treatment. In immunoblotting using a rabbit antibody, the antigenicity against ovalbumin or ovomucoid in acid-treated egg white was decreased but the antigenicity against Ara h 1 or Ara h 2 in peanut treated with pH 2 acetic acid was completely undetected. The allergenicity of ovalbumin and peanut fell significantly to 1/1022 and 1/5380, respectively, when measured as IC50 in the sample treated with pH 2.0 acetic acid. CONCLUSION: This study showed that acid treatment was more effective in peanut and barely effective in ovomucoid. This may contribute to the development of hypoallergenic food and clinical management of food allergy. © 2016 Society of Chemical Industry.

Lycopersicon esculentum Extract Enhances Cognitive Function and Hippocampal Neurogenesis in Aged Mice.

A decrease in adult neurogenesis is associated with the aging process, and this decrease is closely related to memory impairment. Tomato (Lycopersicon esculentum) is a fruit with diverse bioactive nutrients that is consumed worldwide. In this study, we investigated the cognition-enhancing effect of tomato ethanolic extracts (TEE) in aged mice. Six weeks of oral TEE administration in 12-month-old aged mice significantly increased their exploration time of novel objects when compared to vehicle-treated mice. The TEE supplement increased doublecortin (DCX)-positive cells and postsynaptic density-95 (PSD95) expression in mice hippocampus. Moreover, we found an increased expression of brain-derived neurotrophic factor (BDNF) and subsequently-activated extracellular-signal-regulated kinase (ERK)/cAMP response element binding (CREB) signaling pathway in the TEE-supplemented mice hippocampus. In conclusion, the oral administration of TEE exhibits a cognition-enhancing effect, and the putative underlying mechanism is the induction of BDNF signaling-mediated proliferation and synapse formation in the hippocampus. These findings indicate that TEE could be a candidate for treatment of age-related memory impairment and neurodegenerative disorders.

Baicalein induces CD4(+)Foxp3(+) T cells and enhances intestinal barrier function in a mouse model of food allergy.

The incidence of food allergy, which is triggered by allergen permeation of the gastrointestinal tract followed by a T-helper (Th) 2-mediated immune response, has been increasing annually worldwide. We examined the effects of baicalein (5,6,7-trihydroxyflavone), a flavonoid from Scutellaria baicalensis used in oriental herbal medicine, on regulatory T (Treg) cell induction and intestinal barrier function through the regulation of tight junctions in a mouse model of food allergy. An allergic response was induced by oral challenge with ovalbumin, and the incidence of allergic symptoms and T cell-related activity in the mesenteric lymph nodes were analyzed with and without the presence of baicalein. Our results demonstrated that the administration of baicalein ameliorated the symptoms of food allergy and attenuated serum IgE and effector T cells. However, Treg-related factors were up-regulated by baicalein. Furthermore, baicalein was shown to enhance intestinal barrier function through the regulation of tight junctions. We also found that baicalein treatment induced the differentiation of Treg cells via aryl hydrocarbon receptors (AhRs). Thus, the action of baicalein as an agonist of AhR can induce Treg differentiation and enhance barrier function, suggesting that baicalein might serve as an effective immune regulator derived from foods for the treatment of food allergy.

Rosae Multiflorae Fructus Hot Water Extract Inhibits a Murine Allergic Asthma Via the Suppression of Th2 Cytokine Production and Histamine Release from Mast Cells.

Mast cell-mediated anaphylactic reactions are involved in many allergic diseases, including asthma and allergic rhinitis. In Korea, where it has been used as a traditional medicine, Rosae Multiflorae fructus (RMF) is known to have potent antioxidative, analgesic, and anti-inflammatory activities and to have no obvious acute toxicity. However, its specific effect on asthma is still unknown. In this study, we evaluated whether or not RMF hot water extracts (RMFW) could inhibit ovalbumin (OVA)-induced allergic asthma and evaluated compound 48/80-induced mast cell activation to elucidate the mechanisms of asthma inhibition by RMFW. Oral administration of RMFW decreased the number of eosinophils and lymphocytes in the lungs of mice challenged by OVA and downregulated histological changes such as eosinophil infiltration, mucus accumulation, goblet cell hyperplasia, and collagen fiber deposits. In addition, RMFW significantly reduced T helper 2 cytokines, TNF-α, IL-4, and IL-6 levels in the BAL fluid of mice challenged by OVA. Moreover, RMFW suppressed compound 48/80-induced rat peritoneal mast cell degranulation and inhibited histamine release from mast cells induced by compound 48/80 in a dose-dependent manner. These results suggest that RMFW may act as an antiallergic agent by inhibitingTh2 cytokine production from Th2 cells and histamine release from mast cells, and could be used as a therapy for patients with Th2-mediated or mast cell-mediated allergic diseases.

Regulatory T Cell Induced by Poria cocos Bark Exert Therapeutic Effects in Murine Models of Atopic Dermatitis and Food Allergy.

The prevalence of allergic disorders including atopic dermatitis (AD) and food allergy (FA) has increased dramatically in pediatric populations, but there is no effective drug available for their management. Therefore, trials are required for the development of safe therapeutic agents such as herbal medicines. We determined whether orally administered Poria cocos bark (PCB) extract could exert immunosuppressive effects on allergic and inflammatory symptoms of AD and FA. For both AD, which was induced using house dust mite extract, and FA, which was induced by exposure to ovalbumin, model mice were orally treated with PCB extract for 62 days and 18 days, respectively. We also investigated the inductive effect of PCB extract on the generation and maintenance of Foxp3(+)CD4(+) regulatory T cells (Tregs). The symptoms of AD and FA were ameliorated by the administration of PCB extract. Furthermore, PCB extract inhibited the Th2-related cytokines and increased the population of Foxp3(+)CD4(+) Tregs in both AD and FA models. In ex vivo experiments, PCB extract promoted the functional differentiation of Foxp3(+)CD4(+) Tregs, which is dependent on aryl hydrocarbon receptor activation. Thus, PCB extract has potential as an oral immune suppressor for the treatment of AD and FA through the generation of Tregs.

Sarcodon aspratus Extract Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mouse Colon and Mesenteric Lymph Nodes.

Mushrooms have been previously investigated for their immune-modulating and anti-inflammatory properties. We examined whether the anti-inflammatory properties of Sarcodon aspratus ethanol extract (SAE) could elicit protective effects against dextran sulfate sodium (DSS)-induced colitis in vivo. Male C57/BL6 mice were randomly assigned to 1 of 4 treatment groups: control (CON; n = 8), DSS-treated (DSS; n = 9), DSS+SAE at 50 mg/kg BW (SAE50; n = 8), and DSS+SAE at 200 mg/kg BW groups (SAE200; n = 9). DSS treatment induced significant weight loss, which was significantly recovered by SAE200. Although SAE did not affect DSS-mediated reductions in colon length, it improved diarrhea and rectal bleeding induced by DSS. SAE at 200 mg/kg BW significantly attenuated IL-6 and enhanced IL-10 expression in mesenteric lymph nodes (MLN), and significantly reduced IL-6 levels in splenocytes. SAE200 also significantly attenuated DSS-induced increase in IL-6 and IL-1ß, and reductions in IL-10 in colon tissue. High levels of SAE were also observed to significantly decrease inflammatory COX-2 expression that was upregulated by DSS in mice colon. These findings may have relevance for novel therapeutic strategies to mitigate inflammatory bowel disease-relevant inflammatory responses, via the direct and indirect anti-inflammatory activity of SAE. We also found that SAE harbors significant quantities of total fiber and ß-glucan, suggesting a possible role for these components in protection against DSS-mediated colitis.

Citrus Tachibana Leaf Extract Mitigates Symptoms of Food Allergy by Inhibiting Th2-Associated Responses.

Although the incidence of food allergy continues to rise, there have been no effective therapeutic strategies. Citrus fruits contain a number of bioactive flavonoids with immune-regulatory functions. The objective of this study was to determine whether Citrus tachibana (fruit body with peel, leaves, and branch) can protect against the development of food allergy and the mechanism behind it, and to identify the active compound(s) responsible. We found that C. tachibana leaf extract (CLE) mitigated ovalbumin (OVA)-induced food allergy symptoms including increased rectal temperature, diarrhea, and anaphylaxis. This mitigation was likely due to CLE-mediated decreases in cytokine release from T-helper 2 cells (Th2 cells) in mesenteric lymph nodes. Moreover, higher levels of CLE attenuated systemic Th2 cell-mediated responses in mouse splenocytes sensitized with OVA+Alum. This was evidenced by CLE-mediated reductions in Th2 cytokine release, including interleukin (IL)-4, IL-5, and IL-13, but not the Th1 cytokines IL-12 and interferon (IFN)-γ, which was attributable to decreased gene expression levels. We also identified kaempferol as the most potent compound for reducing Th2-associated responses in splenocytes. The findings of this study suggest that CLE suppresses Th2-cell-mediated immune responses, contributing to alleviation of food allergy symptoms, and that kaempferol is a flavonoid with potential antiallergenic activity that targets Th2 cell-induced responses.

Oral Administration of Achyranthis radix Extract Prevents TMA-induced Allergic Contact Dermatitis by Regulating Th2 Cytokine and Chemokine Production in Vivo.

Allergic contact dermatitis (ACD) remains a major skin disease in many countries, necessitating the discovery of novel and effective anti-ACD agents. In this study, we investigated the preventive effects of Achyranthis radix extract (AcRE) on trimellitic anhydride (TMA)-induced dermatitis and the potential mechanism of action involved. Oral administration of AcRE and prednisolone (PS) significantly suppressed TMA-induced increases in ear and epidermal thickness, and IgE expression. In addition, abnormal expression of IL-1ß and TNF-α protein and mRNA was also significantly attenuated by oral administration of AcRE. Treatment with AcRE also significantly suppressed TMA-induced IL-4 and IL-13 cytokines and mRNA expression in vivo. Moreover, AcRE strongly suppressed TMA-induced IL-4 and IL-5 production in draining lymph nodes, as well as OVA-induced IL-4 and IL-5 expression in primary cultured splenocytes. Interestingly, AcRE suppressed IL-4-induced STAT6 phosphorylation in both primary cultured splenocytes and HaCaT cells, and TMA-induced GATA3 mRNA expression ex vivo. AcRE also suppressed TMA-mediated CCL11 and IL-4-induced CCL26 mRNA expression and infiltration of CCR3 positive cells. The major compounds from AcRE were identified as gentisic acid (0.64 ± 0.2 µg/g dry weight of AcRE), protocatechuic acid (2.69 ± 0.1 µg/g dry weight of AcRE), 4-hydroxybenzoic acid (5.59 ± 0.3 µg/g dry weight of AcRE), caffeic acid (4.21 ± 0.1 µg/g dry weight of AcRE), and ferulic acid (14.78 ± 0.4 ± 0.3 µg/g dry weight of AcRE). Taken together, these results suggest that AcRE has potential for development as an agent to prevent and treat allergic contact dermatitis.

Food and Natural Materials Target Mechanisms to Effectively Regulate Allergic Responses.

An immune hypersensitivity disorder called allergy is caused by diverse allergens entering the body via skin contact, injection, ingestion, and/or inhalation. These allergic responses may develop into allergic disorders, including inflammations such as atopic dermatitis, asthma, anaphylaxis, food allergies, and allergic rhinitis. Several drugs have been developed to treat these allergic disorders; however, long-term intake of these drugs could have adverse effects. As an alternative to these medicines, food and natural materials that ameliorate allergic disorder symptoms without producing any side effects can be consumed. Food and natural materials can effectively regulate successive allergic responses in an allergic chain-reaction mechanism in the following ways: [1] Inhibition of allergen permeation via paracellular diffusion into epithelial cells, [2] suppression of type 2 T-helper (Th) cell-related cytokine production by regulating Th1/Th2 balance, [3] inhibition of pathogenic effector CD4(+) T cell differentiation by inducing regulatory T cells (Treg), and [4] inhibition of degranulation in mast cells. The immunomodulatory effects of food and natural materials on each target mechanism were scientifically verified and shown to alleviate allergic disorder symptoms. Furthermore, consumption of certain food and natural materials such as fenugreek, skullcap, chitin/chitosan, and cheonggukjang as anti-allergics have merits such as safety (no adverse side effects), multiple suppressive effects (as a mixture would contain various components that are active against allergic responses), and ease of consumption when required. These merits and anti-allergic properties of food and natural materials help control various allergic disorders.

Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers.

Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function.

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.

Enhancing Effect of Trachelogenin from Trachelospermi caulis Extract on Intestinal Barrier Function.

Trachelospermi caulis is used widely as an herbal medicine in oriental countries to attenuate fever and pain. We wished to reveal the novel function of this herb and its active component on barrier function in intestinal epithelial cells. Monolayers of intestinal epithelial cells (Caco-2) were used to evaluate the transepithelial electrical resistance (TEER) and quantity of permeated ovalbumin (OVA) as indices of barrier function. T. caulis increased TEER values on cell monolayers and decreased OVA permeation across cell monolayers. To ascertain the active component of T. caulis, the extract was isolated to five fractions, and the effect of each of these fractions on intestinal barrier function examined. Chloroform and ethyl acetate fractions showed increased TEER values and decreased OVA flux. Chloroform and ethyl acetate fractions contained mainly trachelogenin and its glycoside, tracheloside. Trachelogenin increased TEER values and decreased OVA flux by enhancing the tight-junction protein occludin (but not tracheloside) in Caco-2 monolayers. These findings demonstrated that trachelogenin, an active component of T. caulis, might help to attenuate food allergy or inflammatory bowel disease through inhibition of allergen permeation or enhancement of the intestinal barrier.