Epilobiumpyrricholophum Extract Suppresses Porcine Pancreatic Elastase and Cigarette Smoke Extract-Induced Inflammatory response in a Chronic Obstructive Pulmonary Disease Model.

Chronic airway exposure to harmful substances, such as deleterious gases, cigarette smoke (CS), and particulate matter, triggers chronic obstructive pulmonary disease (COPD), characterized by impaired lung function and unbridled immune responses. Emerging epigenomic and genomic evidence suggests that excessive recruitment of alveolar macrophages and neutrophils contributes to COPD pathogenesis by producing various inflammatory mediators, such as reactive oxygen species (ROS), neutrophil elastase, interleukin (IL) 6, and IL8. Recent studies showed that Epilobium species attenuated ROS, myeloperoxidase, and inflammatory cytokine production in murine and human innate immune cells. Although the Epilobium genus exerts anti-inflammatory, antioxidant, and antimicrobial effects, the question of whether the Epilobium species regulate lung inflammation and innate immune response in COPD has not been investigated. In this study, Epilobium pyrricholophum extract (EPE) suppressed inflammatory cell recruitment and clinical symptoms in porcine pancreatic elastase and CS extract-induced COPD mice. In addition, EPE attenuated inflammatory gene expression by suppressing MAPKs and NFκB activity. Furthermore, UPLC-Q-TOF MS analyses revealed the anti-inflammatory effects of the identified phytochemical constituents of EPE. Collectively, our studies revealed that EPE represses the innate immune response and inflammatory gene expression in COPD pathogenesis in mice. These findings provide insights into new therapeutic approaches for treating COPD.

Miquelianin Inhibits Allergic Responses in Mice by Suppressing CD4+ T Cell Proliferation.

Allergic diseases, including atopic dermatitis (AD), induce type 2 helper T (Th2) cell-dominant immune responses. Miquelianin (quercetin 3-O-glucuronide, MQL) is an active compound in Rosae multiflorae fructus extract with anti-allergic properties. Here, we investigate the anti-allergic effects of MQL in an ovalbumin (OVA)-induced Th2-dominant mouse model and the associated mechanisms. Oral MQL suppressed cytokine and IL-2 production and proliferation of Th2 cells and upregulated heme oxygenase-1 (HO-1) in splenocytes. Ex vivo MQL suppressed Th1- and Th2-related immune responses by inhibiting CD4+ T cell proliferation, and upregulated HO-1 in CD4+ T cells by activating C-Raf-ERK1/2-Nrf2 pathway via induction of reactive oxygen species generation. In a trimellitic anhydride-induced AD-like mouse model, both topical and oral MQL ameliorated AD symptoms by suppressing Th2 immune responses. Our results suggest that MQL is a potential therapeutic agent for CD4+ T cell-mediated diseases, including allergic diseases.

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.

Preventive Effect of Bupleurum chinense on Nasal Inflammation via Suppressing T Helper Type 2, Eosinophil and Mast Cell Activation.

Bupleurum chinense is distributed in East Asia and has been used as a traditional herbal medicine for more than a thousand years. Though B. chinense has been reported to have immunomodulatory, anti-inflammatory, anti-oxidant, hepato-protective, antipyretic, analgesic and antifibrotic effects, its specific effect on allergic rhinitis disease has not been clarified. In this study, we investigated the anti-allergic and anti-inflammation effects of B. chinense extract (BCE) in an ovalbumin (OVA)-induced allergic rhinitis (AR) mouse model. Oral administration of BCE in a dose-independent manner regulated the balance of Th1/Th2/Treg cell differentiation in AR mice. Accordingly, BCE attenuated the expression of Th2-related cytokines such as IL-4, IL-5 and IL-13 in nasal lavage fluid (NALF) and nasal tissue and up-regulated the secretion of Th1/Treg cells including IL-10, IL-12 and IFN- γ . Also, BCE inhibited the formation and migration of eosinophils to the nasal mucosa and NALF, as well as suppressed CCL24, an eosinophil-specific chemoattractant in NALF. The levels of anti-OVA specific IgE and anti-OVA specific IgG1 were decreased, and as a result, the allergic response was attenuated by BCE via inhibiting mast cells accumulation in nasal mucosa and serum histamine release. The nasal allergy symptoms, nasal mucosal swelling, epithelial barrier disruption and mucus hyperplasia were obviously ameliorated. These results suggest that BCE may have therapeutic potential for treating allergic rhinitis through modulating the accumulation and activation of important leukocytes in the immune system such as Th1, Th2, Treg, eosinophils and mast cells.

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.

The protective role of Piper nigrum fruit extract in an ovalbumin-induced allergic rhinitis by targeting of NFκBp65 and STAT3 signalings.

Piper nigrum L. is commonly used as a traditional medicine and food in many countries. It 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 rhinitis (AR) has been unclear. In the present study, an OVA-induced AR mice model were established to investigate the anti-allergic, anti-inflammation properties of P. nigrum fruit extract (PNE). Oral administrations of PNE inhibited the allergic nasal symptoms including rubbing and sneezing in the early-phage of AR. In both NALF and nasal tissue, PNE suppressed the inflammatory cells accumulation, specifically with eosinophils in NALF. Additionally, PNE prevented the activation of STAT3 and NFκBp65 signaling in the cytoplasm which led to increasing the synthesis of the anti-inflammatory Th1 cytokines and suppressing the inflammatory Th2, Th17 cytokines. These obtained results suggest that PNE has the promising strategy for immunotherapy in allergic rhinitis disease.

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.

Immune-Enhancing Effect of Nanometric Lactobacillus plantarum nF1 (nLp-nF1) in a Mouse Model of Cyclophosphamide-Induced Immunosuppression.

Nanometric Lactobacillus plantarum nF1 (nLp-nF1) is a biogenics consisting of dead L. plantarum cells pretreated with heat and a nanodispersion process. In this study, we investigated the immune-enhancing effects of nLp-nF1 in vivo and in vitro. To evaluate the immunostimulatory effects of nLp-nF1, mice immunosuppressed by cyclophosphamide (CPP) treatment were administered with nLp-nF1. As expected, CPP restricted the immune response of mice, whereas oral administration of nLp-nF1 significantly increased the total IgG in the serum, and cytokine production (interleukin-12 (IL-12) and tumor necrosis factor alpha (TNF-α)) in bone marrow cells. Furthermore, nLp-nF1 enhanced the production of splenic cytokines such as IL-12, TNF-α, and interferon gamma (IFN-γ). In vitro, nLp-nF1 stimulated the immune response by enhancing the production of cytokines such as IL-12, TNF-α, and IFN-γ. Moreover, nLp-nF1 given a food additive enhanced the immune responses when combined with various food materials in vitro. These results suggest that nLp-nF1 could be used to strengthen the immune system and recover normal immunity in people with a weak immune system, such as children, the elderly, and patients.

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.

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.

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.

Skullcap (Scutellaria baicalensis) extract and its active compound, wogonin, inhibit ovalbumin-induced Th2-mediated response.

Skullcap (Scutellaria baicalensis) has been widely used as a dietary ingredient and traditional herbal medicine owing to its anti-inflammatory and anticancer properties. In this study, we investigated the anti-allergic effects of skullcap and its active compounds, focusing on T cell-mediated responses ex vivo and in vivo. Splenocytes from mice sensitized with ovalbumin (OVA) were isolated for analyses of cytokine production and cell viability. Mice sensitized with OVA were orally administered skullcap or wogonin for 16 days, and then immunoglobulin (Ig) and cytokine levels were measured by enzyme-linked immunosorbent assays. Treatment with skullcap significantly inhibited interleukin (IL)-4 production without reduction of cell viability. Moreover, wogonin, but not baicalin and baicalein, suppressed IL-4 and interferon-gamma production. In vivo, skullcap and wogonin downregulated OVA-induced Th2 immune responses, especially IgE and IL-5 prediction. Wogonin as an active component of skullcap may be applied as a therapeutic agent for IgE- and IL-5-mediated allergic disorders.

Antiallergic effect of Trigonella foenum-graecum L. extracts on allergic skin inflammation induced by trimellitic anhydride in BALB/c mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Fenugreek (Trigonella foenum-graecum L.) has a wide variety of therapeutic properties for allergic and inflammatory diseases and is used as a traditional functional food, but its antiallergenic mechanism in these diseases is yet to be clearly elucidated. AIM: In the present study, we investigated the antiallergic activity of fenugreek extract using trimellitic anhydride (TMA)-induced contact hypersensitivity (CHS) mice in vivo and ovalbumin (OVA)-immunized BALB/c mice ex vivo as represented model of T-helper (Th) 2-induced allergy. MATERIALS AND METHODS: BALB/c mice were administered 250 mg/kg body weight (BW) of fenugreek extract for 7 days after sensitization and challenge treatment with 2-5% TMA. Ear thickness were noted, and the infiltration of eosinophils and mast cells was investigated by hematoxylin and eosin (H&E) and toluidine blue (TB) staining. The supernatants from homogenized ear and splenocytes were used for cytokine determination using ELISA. In addition, splenocytes from OVA-immunized BALB/c mice were treated with fenugreek extract ex vivo. The levels of cytokines present in the supernatants were determined by ELISA. The mRNA expression of T-box transcription factor 21 gene (T-bet), GATA-binding protein 3 (GATA-3), interferon (IFN)-γ, and interleukin (IL)-4 were evaluated by real-time RT-PCR. RESULTS: Fenugreek extract was found to reduce ear thickness as well as the infiltration of eosinophils and mast cells. In homogenized ear, the production of IL-4, IL-5, IL-13, and IL-1ß was suppressed. To determine the mechanism by which fenugreek extract inhibits allergic skin inflammation, detailed studies were conducted revealing that fenugreek extract prevented differentiation into Th2 cells in the splenocytes of OVA-induced allergic mice, resulting from suppressing the secretion of IL-4 and mRNA expression of GATA-3, an IL-4 transcription factor. In earlier phase, these extracts enhanced the secretion of IFN-γ, the mRNA expression of T-bet, an IFN-γ transcription factor, and the number of IFN-γ-producing CD4(+) T cells. CONCLUSIONS: These results indicate that fenugreek extract cures Th2-induced allergic skin inflammation by enhancing Th1 differentiation. These data suggest that fenugreek extracts may prove to be an useful therapeutic agent on allergic inflammatory diseases as traditional use as well as Th2-mediated allergic response.