Inhibition Of Histamine Release Research Articles

Vaccinium angustifolium Root Extract Suppresses FcɛRI Expression in Human Basophilic KU812F Cells.

Vaccinium angustifolium, commonly known as the lowbush blueberry, is a rich source of flavonoids, with which various human physiological activities have been associated. The present study focuses on the investigation of the effect of the methanolic extract of V. angustifolium root extract (VAE) on high affinity immunoglobulin E receptor (FcɛRI) α chain antibody (CRA-1)-induced allergic reaction in human basophilic KU812F cells. The total phenolic content of VAE was found to be 170±1.9 mg gallic acid equivalents/g. Flow cytometry analysis revealed that the cell surface expression of FcɛRI was suppressed in a concentration-dependent manner upon culture with VAE. Reverse-transcriptase polymerase chain reaction analysis showed that the mRNA level of the FcɛRI α chain was reduced in a concentration-dependent manner as a result of VAE treatment. Western blot analysis revealed that the protein expression of FcɛRI and the phosphorylation of extracellular signal-regulated kinases (ERK) 1/2 were concentration-dependently inhibited by VAE. We determined that VAE inhibited anti-CRA-1-induced histamine release, in addition to the elevation of intracellular calcium concentration ([Ca2+]i), in a concentration-dependent manner. These results indicate that VAE may exert an anti-allergic effect via the inhibition of calcium influx and histamine release, which occurs as a result of the down-regulation of FcɛRI expression through inhibition of ERK 1/2 activation.

Mast Cells Promote Seasonal White Adipose Beiging in Humans.

Human subcutaneous (SC) white adipose tissue (WAT) increases the expression of beige adipocyte genes in the winter. Studies in rodents suggest that a number of immune mediators are important in the beiging response. We studied the seasonal beiging response in SC WAT from lean humans. We measured the gene expression of various immune cell markers and performed multivariate analysis of the gene expression data to identify genes that predict UCP1. Interleukin (IL)-4 and, unexpectedly, the mast cell marker CPA3 predicted UCP1 gene expression. Therefore, we investigated the effects of mast cells on UCP1 induction by adipocytes. TIB64 mast cells responded to cold by releasing histamine and IL-4, and this medium stimulated UCP1 expression and lipolysis by 3T3-L1 adipocytes. Pharmacological block of mast cell degranulation potently inhibited histamine release by mast cells and inhibited adipocyte UCP1 mRNA induction by conditioned medium (CM). Consistently, the histamine receptor antagonist chlorpheniramine potently inhibited adipocyte UCP1 mRNA induction by mast cell CM. Together, these data show that mast cells sense colder temperatures, release factors that promote UCP1 expression, and are an important immune cell type in the beiging response of WAT.

N-glycan in cockroach allergen regulates human basophil function.

IntroductionCockroach allergen exposure elicits cockroach sensitization and poses an increased risk for asthma. However, the major components in cockroach allergen and the mechanisms underlying the induction of cockroach allergen‐induced allergy and asthma remain largely elusive. We sought to examine the role of cockroach‐associated glycan in regulating human basophil function.MethodsN‐linked glycans from naturally purified cockroach allergen Bla g 2 were characterized by MALDI‐TOF mass spectrometry. Binding of cockroach allergen to serum IgE from cockroach allergic subjects was determined by solid‐phase binding immunoassays. Role of cockroach associated glycan in histamine release and IL‐4 production from human basophils was examined. Expression of C‐type lectin receptors (CLRs) and their role in mediating glycan‐uptake in the basophils was also investigated.ResultsMALDI‐TOF mass spectrometric analysis of N‐glycan from Bla g 2 showed complex hybrid‐types of glycans that terminated with mannose, galactose, and/or N‐acetyl glucosamine (GlcNAc). Deglycosylated Bla g 2 showed reduced binding to IgE and was less capable of inducing histamine release from human basophils. In contrast, N‐glycan derived from Bla g 2 significantly inhibited histamine release and IL‐4 production from basophils passively sensitized with serum from cockroach allergic subjects. An analysis of CLRs revealed the expression of DC‐SIGN and DCIR, but not MRC1 and dectin‐1, in human basophils. Neutralizing antibody to DCIR, but not DC‐SIGN, significantly inhibited Bla g 2 uptake by human basophils. A dose‐dependent bindings of cockroach allergen to DCIR was also observed.ConclusionsThese observations indicate a previously unrecognized role for cockroach allergen‐associated glycans in allergen‐induced immune reactions, and DCIR may play a role in mediating the regulation of glycan on basophil function.

Effects of fostriecin on β2-adrenoceptor-driven responses in human mast cells

As part of the intracellular processes leading to mast cell and basophil activation, phosphorylation of key substrates is likely to be important. These processes, mediated by phosphatases, are responsible for regulating phosphorylation. The aim of the present study was to determine effects fostriecin – a selective inhibitor of PP2A (protein phosphatase-2) – on β2-adrenoceptor-driven responses in human mast cells. Here, the effects of fostriecin (PP inhibitors) on the inhibition of histamine release from HLMC, on β-adrenoceptor-driven responses in mast cells and on desensitization were investigated. Long-term incubation (24 h) of mast cells with fostriecin (10−6 M) resulted in a significant (p < 0.001) reduction in the maximal response (from 41.2 [± 3.0] to 29.9 [± 4.2] %) to salbutamol following fostriecin treatment. The results showed that fostriecin pretreatment significantly attenuated the inhibitory effects of salbutamol. Overall, the present study suggested that PP2A has an important role in regulating mast cell β2-adrenoceptors.

Achyranthes japonica Nakai Water Extract Suppresses Binding of IgE Antibody to Cell Surface FcɛRI.

Achyranthes japonica Nakai (AJN) water extract has a variety of physiological properties, including anti-diabetic, anti-cancer, anti-inflammatory, anti-microbial, and anti-oxidative activities. In the present study, the inhibitory effects of AJN extract were investigated in high affinity immunoglobulin E receptor (FcɛRI)-mediated KU812F cells activation. AJN extract showed suppressive effects on histamine release and intracellular calcium [Ca2+]i elevation from anti-FcɛRI antibody (CRA-1)-stimulated cells in a dose-dependent manner. Flow cytometric analysis showed that AJN extract treatment caused a dose-dependent decrease in the cell surface FcɛRI expression and the binding between the cell surface FcɛRI and the IgE antibody. Moreover, reverse transcription-polymerase chain reaction analysis showed that levels of the mRNA for the FcɛRI α chain was decreased by treatment with AJN extract. These results indicate that AJN extract may exert anti-allergic effects via the inhibition of calcium influx and histamine release, which occurs as a result from the down-regulation of the binding of IgE antibody to cell surface FcɛRI. This mechanism may occur through FcɛRI expression inhibition.

MONOMERIC ALLERGOID FROM HOUSE DUST MITE DERMATOPHAGOIDES PTERONYSSINUS: IMMUNOLOGICAL PROPERTIES

Background. The purpose of this study was to characterize the immunologic properties of the monomeric allergoid obtained from house dust mite Dermatophagoides pteronyssinus (D. pteronyssinus) extract. Methods. To obtain monomeric allergoid the extract from D. pteronyssinus (D1) was chemically modified by succinilation and then the degree of modification and total protein content were determined. Analysis of proteins in native D1 or modified sD1 was performed by SDS-PAGE. Determination of the major allergen Der p 1 in the native extract D1 was done by mass-spectrometry method. For measurement of tertiary structure alterations of protein molecules in D1 or recombinant Der p 1 (rDer p 1) after their modification by succinilation the circular dichroism (CD) method was applied. Allergenicity of sD1 was estimated by inhibition of specific IgE binding in ELISA and chemiluminescent analysis using Phadia ImmunoCAP as well as by detection of histamine released from leukocytes of whole blood of Der p sensitized patients after its incubation with D1 or sD1. To evaluate immunogenicity of D1 and sD1 BALB/c mice were i.p. immunized 4 times in 3 week interval with D1 or sD1 with or without adjuvant Al(OH),. The levels of anti-Der p IgE, IgG1 and IgG2a in pulled mice sera were determined by ELISA. Results. Succinilation of D1 extract led to «unfolding» of allergen molecules in modified sD1. The degree ofmodification was 98,9%. Results of SDS-PAGE demonstrated that native D1 and succinilated sD1 extract showed bands at the same molecular mass confirming that succinilation does not influence the size of modified molecule which thus maintains the monomeric nature of the sD1. Mass-spectrometry analysis revealed the presence of major allergen Der p 1 in the native D1 extract. CD method demonstrated the alteration of tertiary structure of succinilated recombinant rDer p 1 that may be extrapolated on the other allergenic proteins in the sD1 extract. Allergenicity of sD1 was significantly reduced in compare to D1 that was confirmed by inhibition of IgE-binding and histamine release from leukocytes of whole blood, Immunization of BALB/c mice with sD1 (with or without Al(OH)3) induced anti-Der p IgE-response which was substantially lower than that of D1 induced. At the same time anti-Der p IgG1 and IgG2a responses after immunization with sD1 (with or without Al(OH)3) were significantly higher than that ofD1 induced. Conclusion. Modification of the extract from house dust mite D. pteronyssinus by succinilation leads to formation of monomeric allergoid possesses low allergenicity and preserved (or even increased) immunogenicity that may a new approach for creation of allergy vaccines for safe and effective allergen-specific immunotherapy.

Agarwood Inhibits Histamine Release from Rat Mast Cells and Reduces Scratching Behavior in Mice: Effect of Agarwood on Histamine Release and Scratching Behavior.

Objectives:This study was conducted to clarify the effects of agarwood on histamine release from mast cells in rats and on the scratching behaviors in mice.Methods:Histamine release from rat mast cells induced by compound 48/80 or concanavalin A (Con A) and compound 48/80-induced scratching behavior in mice were examined to investigate the effects of agarwood. The hyaluronidase activity and the 3’,5’-cyclic adenosine monophosphate (cAMP) levels in mast cells were examined to investigate the mechanisms for the inhibition of histamine release. The correlation between the inhibitory effects of agarwood on histamine release and the content of its typical ingredients, a 2-(2-phenylethyl)chromone derivatives, was analyzed using thin-layer chromatography.Results:Agarwood showed an inhibitory effect on mast-cell histamine release induced by compound 48/80 or Con A without any effect on hyaluronidase activity; this effect involves an increase in the cAMP levels in mast cells. Oral administration of agarwood showed an inhibitory effect on compound 48/80-induced scratching behavior in mice. The inhibitory effects of agarwood on histamine release were quite different, depending on the area where the agarwood was produced, its quality, and its market price. No correlation was found between the inhibitory effects of agarwood on histamine release and the typical ingredients of agarwood, which are 2-(2-phenylethyl)chromone derivatives.Conclusion:These results show that agarwood inhibits histamine release from mast cells partially through an increase in the cAMP levels in cells. We suggest that some active ingredients of agarwood must be effective on oral intake and that agarwood can be used to treat patients with a number of conditions, including urticaria, atopic dermatitis, and bronchial asthma, in which an increase in histamine release occurs. Differences in the pharmacological effects of this crude drug among markets may provide important information for the quality control of this herbal medicine.

Effects of chelidonic acid, a secondary plant metabolite, on mast cell degranulation and adaptive immunity in rats

The present study evaluated the immunomodulatory effects of chelidonic acid, a secondary plant metabolite, with therapeutic potential in allergic disorders, in experimental animals. In mast cell degranulation studies, ovalbumin immunized and challenged rats, chelidonic acid (1, 3 and 10mg/kg, i.p.) dose relatedly prevented ovalbumin challenge induced mast cell degranulation by differing degrees when compared with vehicle treated group, and these effects were comparable with prednisolone (10mg/kg). A reduction in post-challenge mortality was also observed in all treated groups. Further, there were reductions in the blood eosinophil counts and serum IgE levels after chelidonic acid treatment. Chelidonic acid also inhibited histamine release from rat peritoneal mast cells (RPMC) in vitro, in a dose related manner. In tests for adaptive immunity, in rats immunized with sheep RBC, chelidonic acid differentially suppressed the (a) plaque forming cell (PFC) count in rat splenic cells, (b) anti-SRBC antibody titre and serum IgG levels and (c) increases in foot pad thickness in the DTH assay — all of which were comparable with prednisolone. These experimental results are discussed in light of the possible therapeutic potential of chelidonic acid in allergic disorders.

Screening anti-allergic components of Astragali Radix using LAD2 cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method.

Huangqi (Astragali Radix), a traditional Chinese herb, is widely used in clinical therapy in China. In addition, an anti-allergic effect of constituents in Huangqi has been reported in the scientific literature. In the present study, cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method was developed to screen, analyze and identify the anti-allergic components of Huangqi. The Laboratory of Allergic Disease 2 (LAD2) cell was used to establish cell membrane chromatography, which was combined with UHPLC-ESI-MS/MS. The coupled system was then used to screen anti-allergic components from Huangqi. Effects of active components were verified by histamine release assay. A component retained on the LAD2 cell membrane chromatography was identified as formononetin. Bioactivity of formononetin was investigated by histamine release assay in LAD2 cells, and it was found that formononetin could inhibit histamine release in a dose-dependent manner from 1 to 100 μm. The LAD2 cell membrane chromatography online with UHPLC-ESI-MS/MS method is an effective technique for screening the anti-allergic components of Huangqi.

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.

Quercetin ameliorates paclitaxel-induced neuropathic pain by stabilizing mast cells, and subsequently blocking PKCε-dependent activation of TRPV1

Severe painful sensory neuropathy often occurs during paclitaxel chemotherapy. Since paclitaxel can activate mast cell and basophils, whereas quercetin, a polyphenolic flavonoid contained in various plants, which can specifically inhibit histamine release as a mast cell stabilizer. In this study we explore whether quercetin could ameliorate paclitaxel-induced neuropathic pain and elucidated the underlying mechanisms. Quercetin inhibition on histamine release was validated in vitro by detecting histamine release from rat basophilic leukemia (RBL-2H3) cells stimulated with paclitaxel (10 μmol/L). In the in vivo experiments, rats and mice received quercetin (20, 40 mg·kg(-1)·d(-1)) for 40 and 12 d, respectively. Meanwhile, the animals were injected with paclitaxel (2 mg/kg, ip) four times on d 1, 3, 5 and 7. Heat hyperalgesia and mechanical allodynia were evaluated at the different time points. The animals were euthanized and spinal cords and dorsal root ganglions were harvested for analyzing PKCε and TRPV1 expression levels. The plasma histamine levels were assessed in rats on d 31. Pretreatment with quercetin (3, 10, 30 μmol/L) dose-dependently inhibited excessive histamine release from paclitaxel-stimulated RBL-2H3 cells in vitro, and quercetin administration significantly suppressed the high plasma histamine levels in paclitaxel-treated rats. Quercetin administration dose-dependently raised the thresholds for heat hyperalgesia and mechanical allodynia in paclitaxel-treated rats and mice. Furthermore, quercetin administration dose-dependently suppressed the increased expression levels of PKCε and TRPV1 in the spinal cords and DRGs of paclitaxel-treated rats and mice. Moreover, quercetin administration may inhibited the translocation of PKCε from the cytoplasm to the membrane in the spinal cord and DRG of paclitaxel-treated rats. Our results reveal the underlying mechanisms of paclitaxel-induced peripheral neuropathy and demonstrate the therapeutic potential of quercetin for treating this side effect.

Efficacy of a Nasal Spray fromCitrus limonandCydonia oblongafor the Treatment of Hay Fever Symptoms-A Randomized, Placebo Controlled Cross-Over Study

Nasal spray from lemon and quince (LQNS) is used to treat hay fever symptoms and has been shown to inhibit histamine release from mast cells in vitro. Forty-three patients with grass pollen allergy (GPA) were randomized to be treated either with placebo or LQNS for one week, respectively, in a cross-over study. At baseline and after the respective treatments patients were provoked with grass pollen allergen. Outcome parameters were nasal flow measured with rhinomanometry (primary), a nasal symptom score, histamine in the nasal mucus and tolerability. In the per protocol population absolute inspiratory nasal flow 10 and 20 min after provocation was higher with LQNS compared to placebo (-37 ± 87 mL/s; p = 0.027 and -44 ± 85 mL/s; p = 0.022). The nasal symptom score showed a trend (3.3 ± 1.8 in the placebo and 2.8 ± 1.5 in the LQNS group; p = 0.070) in favor of LQNS; the histamine concentration was not significantly different between the groups. Tolerability of both, LQNS and placebo, was rated as very good. LQNS seems to have an anti-allergic effect in patients with GPA. Copyright © 2016 John Wiley & Sons, Ltd.

Mosla punctulata Inhibits Mast Cell-mediated Allergic Reactions Through the Inhibition of Histamine Release and Inflammatory Cytokine Production.

Allergic inflammatory diseases such as food allergy, asthma, sinusitis and atopic dermatitis are increasing worldwide. This study examined the effects of aqueous extract of Mosla punctulata on mast cell-mediated allergic inflammation and studied the possible mechanism of action. Aqueous extract of Mosla punctulata inhibited compound 48/80-induced systemic and immunoglobulin E-mediated local anaphylaxis and it also reduced intracellular calcium level and down-streamed histamine release from mast cells. In addition, aqueous extract of Mosla punctulata decreased gene expression and secretion of tumour necrosis factor alpha, an important proinflammatory cytokine, in mast cells. The inhibitory effect on tumour necrosis factor alpha expression was nuclear factor kappa B dependent. The results indicate that aqueous extract of Mosla punctulata inhibited mast cell-mediated allergic inflammatory reaction by suppressing histamine release and expression of tumour necrosis factor alpha, and involvement of calcium and nuclear factor kappa B in these effects. Hence it can be concluded that, the aqueous extract of Mosla punctulata might be a possible therapeutic candidate for allergic inflammatory disorders.

Quercetin and Its Anti-Allergic Immune Response.

Quercetin is the great representative of polyphenols, flavonoids subgroup, flavonols. Its main natural sources in foods are vegetables such as onions, the most studied quercetin containing foods, and broccoli; fruits (apples, berry crops, and grapes); some herbs; tea; and wine. Quercetin is known for its antioxidant activity in radical scavenging and anti-allergic properties characterized by stimulation of immune system, antiviral activity, inhibition of histamine release, decrease in pro-inflammatory cytokines, leukotrienes creation, and suppresses interleukin IL-4 production. It can improve the Th1/Th2 balance, and restrain antigen-specific IgE antibody formation. It is also effective in the inhibition of enzymes such as lipoxygenase, eosinophil and peroxidase and the suppression of inflammatory mediators. All mentioned mechanisms of action contribute to the anti-inflammatory and immunomodulating properties of quercetin that can be effectively utilized in treatment of late-phase, and late-late-phase bronchial asthma responses, allergic rhinitis and restricted peanut-induced anaphylactic reactions. Plant extract of quercetin is the main ingredient of many potential anti-allergic drugs, supplements and enriched products, which is more competent in inhibiting of IL-8 than cromolyn (anti-allergic drug disodium cromoglycate) and suppresses IL-6 and cytosolic calcium level increase.

Effects of Dendritic Cell Subset Manipulation on Airway Allergy in a Mouse Model

Background: Two major distinct subsets of dendritic cells (DCs) are arranged to regulate immune responses: DEC-205+ DCs drive Th1 polarization and 33D1+ DCs establish Th2 dominancy. Th1 polarization can be achieved either by depletion of 33D1+ DCs with a 33D1-specific monoclonal antibody (mAb) or by activation of DEC-205+ DCs via intraperitoneal injection of α-galactosylceramide (α-GalCer). We studied the effect of 33D1+ DC depletion or DEC-205+ DC activation in vivo using an established mouse model of allergic rhinitis (AR). Methods: Mice were injected intraperitoneally with OVA plus alum and challenged 4 times with daily intranasal administration of OVA. Immediately after the last challenge, allergic symptoms such as sneezing and nasal rubbing as well as the number of cells in the bronchoalveolar lavage fluid (BALF) and nasal lavage fluid (NALF) were counted. The levels of serum OVA-specific IgG1, IgG2a, and IgE were also determined by ELISA. Results: The allergic symptom scores were significantly decreased in 33D1+ DC-depleted or DEC-205+ DC-activated AR mice. The levels of OVA-specific IgG1, IgG2a, and IgE, and the number of NALF cells, but not BALF cells, were reduced in 33D1+ DC-depleted but not in DEC-205+ DC-activated AR mice. Moreover, the activated DEC-205+ DCs suppressed histamine release from IgE-sensitized mast cells, probably through IL-12 secretion. Conclusions: The manipulation of innate DC subsets may provide a new therapeutic strategy for controlling various allergic diseases by reducing histamine release from IgE-sensitized mast cells by driving the immune response towards Th1 dominancy via activation of DEC-205+ DCs in vivo.

Effect of Chicoric Acid on Mast Cell-Mediated Allergic Inflammation in Vitro and in Vivo.

Chicoric acid (dicaffeoyl-tartaric acid), is a natural phenolic compound found in a number of plants, such as chicory (Cichorium intybus) and Echinacea (Echinacea purpurea), which possesses antioxidant, anti-inflammatory, antiviral, and analgesic activities. Although these biological effects of chicoric acid have been investigated, there are no reports of its antiallergic-related anti-inflammatory effects in human mast cells (HMC)-1 or anaphylactic activity in a mouse model. Therefore, we investigated the antiallergic-related anti-inflammatory effect of chicoric acid and its underlying mechanisms of action using phorbol-12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated HMC-1 cells. Chicoric acid decreased the mRNA expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. We studied the inhibitory effects of chicoric acid on the nuclear translocation of nuclear factor kappa B (NF-κB) and activation of caspase-1. However, mitogen-activated protein kinase (MAPK) activation was not sufficient to abrogate the stimulus. In addition, we investigated the ability of chicoric acid to inhibit compound 48/80-induced systemic anaphylaxis in vivo. Oral administration of chicoric acid at 20 mg/kg inhibited histamine release and protected mice against compound 48/80-induced anaphylactic mortality. These results suggest that chicoric acid has an antiallergic-related anti-inflammatory effect that involves modulating mast cell-mediated allergic responses. Therefore, chicoric acid could be an efficacious agent for allergy-related inflammatory disorders.

The natural compound nujiangexanthone A suppresses mast cell activation and allergic asthma

Mast cells play an important role in allergic diseases such as asthma, allergic rhinitis and atopic dermatitis. The genus Garcinia of the family Guttiferae is well known as a prolific source of polycyclic polyprenylated acylphloroglucinols and bioactive prenylated xanthones, which exhibit various biological activities including antibacterial, antifungal, anti-inflammatory, antioxidant, and cytotoxic effects. Nujiangexanthone A (N7) is a novel compound isolated from the leaves of Garcinia nujiangensis. In this paper, we sought to determine the anti-allergic and anti-inflammation activity of N7 in vivo and its mechanism in vitro. We found N7 suppressed IgE/Ag induced mast cell activiation, including degranulation and production of cytokines and eicosanoids, through inhibiting Src kinase activity and Syk dependent pathways. N7 inhibited histamine release, prostaglandin D2 and leukotriene C4 generation in mast cell dependent passive cutaneous anaphylaxis animal model. We also found N7 inhibited the IL-4, IL-5, IL-13 and IgE levels in ovalbumin-induced asthma model. Histological studies demonstrated that N7 substantially inhibited OVA-induced cellular infiltration and increased mucus production in the lung tissue. Our study reveals the anti-allergic function of N7, thereby suggesting the utility of this compound as a possible novel agent for preventing mast cell-related immediate and delayed allergic diseases.

Phenolic constituents of the Bangladeshi medicinal plant Pothos scandens and their anti-estrogenic, hyaluronidase inhibition, and histamine release inhibitory activities

Extracts from the stem and roots of the Bangladeshi medicinal plant Pothos scandens L. (Araceae) were isolated, and three hemiterpene glucoside aromatic esters, pothobanosides A (1), B (2), and C (3), and a phenylisobutanoid, pothobanol (4), along with 14 known compounds, were characterized. The isolates were tested for their estrogenic/anti-estrogenic activity using the estrogen-responsive human breast cancer cell lines MCF-7 and T47D, and syringoyl derivatives (2, 3, and canthoside B) showed strong inhibitory activity against both cell lines. Their less oxygenated analogs (1, and markhamioside F) were almost inactive. The isolates were also evaluated for hyaluronidase and histamine release inhibitory activities, and pothobanoside A (1) showed significant hyaluronidase inhibitory activity among the isolated compounds, which was similar to that of the positive control rosmarinic acid. Because hyaluronidase produces an angiogenic response that has been implicated in tumor invasiveness and metastasis, 1 could be valuable as an anti-tumor compound with a different mechanism of action from related compounds (2, 3). Pothobanoside C (3) and pothobanol (4) were also found to inhibit histamine release to a similar degree to the positive control epigallocatechin 3-O-(3″-O-methyl)-gallate. The histamine release inhibitory potency of these isolates may support the traditional uses of this plant in folk medicine.

Combination of new multifunctional molecules for erythematotelangiectatic rosacea disorder.

BackgroundRosacea, a common chronic skin disorder, is currently managed by patient education, pharmacological drugs, medical devices (laser and light therapies), and use of proper skin cares. Unfortunately, none of these actual treatments used alone or in combination is curative, and so we proposed a dermocosmetic active ingredient to mitigate some aspects of the rosacea and particularly for erythematotelangiectatic rosacea.MethodsDermocosmetic active ingredient is composed of three glucosylated derivatives of natural plants hydroxybenzoic acid and hydroxycinnamic acids (rosmarinic acid, gallic acid, and caffeic acid). Anti-inflammatory, anti-angiogenesis, and anti-degranulation studies were done on cellular models (keratinocytes, mast cells, and endothelial cells). Efficiency of the active ingredient in comparison to placebo was assessed clinically on human volunteers having erythematotelangiectatic rosacea. The active and placebo were applied topically twice a day for 28 days. Biometrical analyses were done using a siascope tool.ResultsWe found that the active ingredient decreases inflammation (inhibition of interleukin-8 and tumor necrosis factor release), decreases degranulation of mast cells (inhibition of histamine release), and controls angiogenesis mechanism (inhibition of the production of vascular endothelial growth factor and neovessel formation) on cellular models. Study on human volunteers confirmed macroscopically the efficiency of this active ingredient, as we observed no neovessel formation and less visible vessels.ConclusionAlthough rosacea is a skin condition disorder that is difficult to heal, the studies have shown that this active ingredient could be a dermocosmetic support, especially for erythematotelangiectatic rosacea armamentarium. The active ingredient was topically applied on the face for 28 days and improved erythematotelangiectatic rosacea symptoms either by decreasing them (vessels are less visible) or by limiting their development (any neovessels). The active ingredient decreases inflammation (inhibition of interleukin-8 and tumor necrosis factor release), decreases degranulation of mast cells (inhibition of histamine release), and limits the angiogenesis process (inhibition of vascular endothelial growth factor production and neovessel formation).

Effect of α-asarone on angiogenesis and matrix metalloproteinase

α-Asarone is a main component of Acorus gramineus widely known as an oriental traditional medicinal stuff. A. gramineus has been known to have a variety of medicinal efficacies such as anti-gastric ulcer and anti-allergic activities, inhibition of histamine release and antioxidant effect. However, its effect on angiogenesis remains unclear. The aim of this study was to investigate the effect of α-asarone on induction of angiogenesis through modulation of matrix metalloproteinase (MMP). First of all, MTT assay was performed to evaluate the effect of α-asarone on cell viability using MTT assay, and then tube formation assay with human umbilical vein endothelial cells (HUVEC) in vitro and rat aorta ring assay ex vivo were carried out to elucidate its effect on angiogenesis. Treatment with α-asarone below 6μM showed no cytotoxicity in human fibrosarcoma cells (HT1080) and HUVEC. It was observed that α-asarone not only promotes tube formation of HUVEC but also induces angiogenesis of rat aorta. In addition, the effects of α-asarone on the expressions of protein and gene were evaluated using western blot analysis and RT-PCR assay. α-Asarone increased the expression levels of MMP-2 and MMP-9 stimulated by phenazine methosulfate (PMS) and phorbol 12-myristate 13-acetate (PMA) in HT1080. Especially, the expression level of antioxidant enzyme such as glutathione reductase was increased in the presence of α-asarone. Therefore, above findings suggest that α-asarone may play an important role in pathological diseases related to MMP and angiogenesis.