Anti-allergic actions of rottlerin from Mallotus philippinensis in experimental mast cell-mediated anaphylactic models

Allergy is an acquired hypersensitivity reaction of the immune system mediated by cross-linking of the allergen-specific IgE-bound high-affinity IgE receptors, leading to immediate mast cell degranulation. Rottlerin is an active molecule isolated from Mallotus philippinensis, a medicinal plant used in Ayurvedic Medicine System for anti-allergic and anti-helminthic treatments. The present study investigated potential anti-allergic effects of rottlerin in animal models of IgE-dependent anaphylaxis and the anti-allergic mechanisms of action of rottlerin in mast cells. Anti-allergic actions of rottlerin were evaluated in passive cutaneous anaphylaxis and passive systemic anaphylaxis mouse models, and in anaphylactic contraction of bronchial rings isolated from sensitized guinea pigs. Direct mast cell-stabilizing effect of rottlerin was examined in RBL-2H3 mast cell line. Anti-allergic signaling mechanisms of action of rottlerin in mast cells were also examined. Rottlerin prevented IgE-mediated cutaneous vascular extravasation, hypothermia, elevation in plasma histamine level and tracheal tissue mast cell degranulation in mice in a dose-dependent manner. In addition, rottlerin suppressed ovalbumin-induced guinea pig bronchial smooth muscle contraction. Furthermore, rottlerin concentration-dependently blocked IgE-mediated immediate release of β-hexosaminidase from RBL-2H3 mast cells. Rottlerin was found to inhibit IgE-induced PLCγ1 and Akt phosphorylation, production of IP3 and rise in cytosolic Ca²⁺ level in mast cells. We report here for the first time that rottlerin possesses anti-allergic activity by blocking IgE-induced mast cell degranulation, providing a foundation for developing rottlerin for the treatment of allergic asthma and other mast cell-mediated allergic disorders.

Morus bombycis extract suppresses mast cell activation and IgE-mediated allergic reaction in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Morus bombycis Koidzumi (MB) is widely distributed throughout Korea, where it is used as a traditional folk remedy for the treatment of allergic diseases including asthma. However, the pharmacological effect and the mechanistic study of MB have not been investigated. We aimed to investigate the anti-allergic activity of MB in vitro and in vivo and the mechanism of its action on mast cells.

MATERIALS AND METHODS

The anti-allergic activity of MB extract (MBE) was assessed using passive cutaneous anaphylaxis (PCA) in mice and mouse bone marrow-derived mast cells (BMMCs) in vitro. The effects of MBE on mast cell activation were evaluated by using the β-hexosaminidase release assay, reverse transcriptase-polymerase chain reaction, enzyme-linked immunosorbent assay, and western blotting analysis.

RESULTS

MBE reversibly inhibited degranulation and generation of cytokines (TNF-α and IL-4) in antigen-stimulated mast cells. With regard to its mechanism of action, MBE inhibited the activation of Lyn and Syk, which have essential roles in degranulation and the production of various inflammatory cytokines. MBE also inhibited the activating phosphorylation of mitogen-activated protein (MAP) kinases, Erk1/2, p38, JNK, and Akt. In agreement with its in vitro effect, MBE significantly inhibited mast cell-mediated PCA reactions in IgE-sensitized mice.

CONCLUSIONS

The present results strongly suggest that MBE exerts an anti-allergic effect, both in vitro and in vivo by inhibiting the Lyn and Syk pathways in mast cells. Therefore, MBE may be useful for the treatment of allergic diseases, including atopic dermatitis and allergic asthma.

The inhibitory activity of atractylenolide Ш, a sesquiterpenoid, on IgE-mediated mast cell activation and passive cutaneous anaphylaxis (PCA)

ETHNOPHARMACOLOGICAL RELEVANCE

AT Ш, a sesquiterpenoid, is the major component of Atractylodes japonica Koidz that has been used as a traditional oriental medicine.

AIM OF THE STUDY

We investigated the anti-allergic activity of AT Ш and its mechanism of action.

MATERIALS AND METHODS

The released amount of β-hexosaminidase in mast cells, a key parameter of degranulation, was measured. Anti-allergic potential of AT Ш was evaluated using passive cutaneous anaphylaxis in vivo. The anti-allergic mechanism of AT Ш was investigated by immunoblotting analysis, RT-PCR and measurement of [Ca(2+)]i in mast cells.

RESULTS

AT Ш significantly inhibited IgE/Ag-mediated degranulation with an IC(50) value (36 ± 4 μM) in RBL-2H3 cells without affecting cell viability. It also suppressed IgE/Ag-mediated passive cutaneous anaphylaxis (PCA) response with an ED(50) value (65 ± 41 mg/kg) in vivo. AT Ш suppressed the production of interleukin (IL-4) and tumor necrosis factor (TNF)-alpha mRNAs more potent than the Src-family kinase inhibitor PP2 in RBL-2H3 cells at all concentrations. In order to elucidate the anti-allergic mechanisms of AT Ш in mast cells, we examined the activated levels of signaling molecules. AT Ш inhibited the phosphorylation of Lyn, Fyn, Syk, LAT, PLCγ, Gab2, Akt, p38, and JNK kinases expression. IgE/Ag-mediated [Ca(2+)]i elevation was significantly inhibited by AT Ш.

CONCLUSIONS

Our study suggests that AT Ш might be used as a therapeutic agent for allergic diseases.

Inula japonica extract inhibits mast cell-mediated allergic reaction and mast cell activation

ETHNOPHARMACOLOGICAL RELEVANCE

The flowers of Inula japonica (Inulae Flos) have long been used in traditional medicine for the treatment of bronchitis, digestive disorders, and inflammation. However, the mechanisms underlying its anti-inflammatory effects remain yet to be elucidated. The objectives of this study were 1) to assess the anti-allergic activity of the ethanol extract of flowers of Inula japonica extract (IFE) in vivo, 2) to investigate the mechanism of its action on mast cells in vitro, and 3) to identify its major phytochemical compositions.

MATERIALS AND METHODS

The anti-allergic activity of IFE was evaluated using mouse bone marrow-derived mast cells (BMMCs) in vitro and a passive cutaneous anaphylaxis (PCA) animal model in vivo. The effects of IFE on mast cell activation were evaluated in terms of degranulation, eicosanoid generation, Ca(2+) influx, and immunoblotting of various signaling molecules.

RESULTS

IFE inhibited degranulation and the generation of eicosanoids (PGD(2) and LTC(4)) in stem cell factor (SCF)-stimulated BMMCs. Biochemical analysis of the SCF-mediated signaling pathways demonstrated that IFE inhibited the activation of multiple downstream signaling processes including mobilization of intracellular Ca(2+) and phosphorylation of the mitogen-activated protein kinases (MAPKs), PLCγ1, and cPLA(2) pathways. When administered orally, IFE attenuated the mast cell-mediated PCA reaction in IgE-sensitized mice. Its major phytochemical composition included three sesquiterpenes, 1-O-acetylbritannilactone, britanin and tomentosin.

CONCLUSIONS

This study suggests that IFE modulates eicosanoids generation and degranulation through the suppression of SCF-mediated signaling pathways that would be beneficial for the prevention of allergic inflammatory diseases. Anti-allergic activity of IFE may be in part attributed particularly to the presence of britanin and tomentosin as major components evidenced by a HPLC analysis.

Polydatin (PD) inhibits IgE-mediated passive cutaneous anaphylaxis in mice by stabilizing mast cells through modulating Ca²⁺ mobilization

Mast cells play a key role in the pathogenesis of asthma and are a promising target for therapeutic intervention in asthma. This study investigated the effects of polydatin (PD), a resveratrol glucoside, on mast cell degranulation upon cross-linking of the high-affinity IgE receptors (FcεRI), as well as the anti-allergic activity of PD in vivo. Herein, we demonstrated that PD treatment for 30 min suppressed FcεRI-mediated mast cell degranulation in a dose-dependent manner. Concomitantly, PD significantly decreased FcεRI-mediated Ca²⁺ increase in mast cells. The suppressive effects of PD on FcεRI-mediated Ca²⁺ increase were largely inhibited by using LaCl₃ to block the Ca²⁺ release-activated Ca²⁺ channels (CRACs). Furthermore, PD significantly inhibited Ca²⁺ entry through CRACs evoked by thapsigargin (TG). Knocking down protein expression of Orai1, the pore-forming subunit of CRACs, significantly decreased PD suppression of FcεRI-induced intracellular Ca²⁺ influx and mast cell degranulation. In a mouse model of mast cell-dependent passive cutaneous anaphylaxis (PCA), in vivo PD administration suppressed mast cell degranulation and inhibited anaphylaxis. Taken together, our data indicate that PD stabilizes mast cells by suppressing FcεRI-induced Ca²⁺ mobilization mainly through inhibiting Ca²⁺ entry via CRACs, thus exerting a protective effect against PCA.

Enhancing effects of trichloroethylene and tetrachloroethylene on type I allergic responses in mice

Trichloroethylene (TCE) and tetrachloroethylene (perchloroethylene; PCE) are commonly identified as environmental contaminants of groundwater. Previously, we investigated the enhancing effects of TCE and PCE on antigen-induced histamine release and inflammatory mediator production in rat mast cells. In this study, to examine the potential effect of TCE and PCE on antigen-induced histamine release from mouse mast cells, mouse bone marrow-derived mast cells (BMMC) were sensitized with anti-dinitrophenol (DNP) monoclonal IgE antibody and then stimulated with DNP-BSA containing with TCE or PCE. Both TCE and PCE significantly enhanced antigen-induced histamine release from BMMC. Next we investigated the effects of TCE and PCE on the passive cutaneous anaphylaxis (PCA) reaction in vivo using ICR mice. TCE and PCE significantly enhanced the PCA reaction in a dose-dependent manner. In addition, we examined the enhancing effects of ingesting small amount of TCE and PCE in drinking water on antigen-stimulated allergic responses. After the ICR mice had ingested TCE or PCE in their drinking water for 2 or 4 weeks, we performed the PCA reaction. Both TCE and PCE ingestion enhanced the PCA reaction in a dose-dependent manner for 4 weeks. These results suggest that exposure to TCE and PCE leads to the augmentation of type I allergic responses in many species.

Evaluation of antiallergic and anti-anaphylactic activity of ethanolic extract of Sanseveiria trifasciata leaves (EEST) in rodents

AIM OF THE STUDY

The leaves and rhizomes of Sansevieria trifasciata are used in folk medicine for treating bronchitis, asthma, cough, snake bite and insect bite etc. The ethanolic extract elicited analgesic, anti-inflammatory and antipyretic activity. Hence, it was decided to study the antiallergic activity of ethanolic extract of S. trifasciata (EEST) on various animal models as well as in vitro conditions, and also to understand possible mechanism of action.

MATERIALS AND METHODS

Ethanolic extract of S. trifasciata leaves (EEST) were prepared by cold maceration followed by concentration and evaporation under reduced pressure on a rotary evaporator to obtain semisolid mass. The various phytoconstituents were analyzed. The acute toxicity study of EEST was carried out in mice. The antiallergic and anaphylactic activities were evaluated using animal models viz. milk induced eosinophilia and leukocytosis, compound 48/80 induced mast cell degranulation, active and passive cutaneous anaphylaxis and histamine induced pedal edema. In addition, EEST effect on Shultz-Dale reaction in sensitized guinea pig ileum in ex vivo and antioxidant activity by free radical scavenging by DPPH method (in vitro) were also studied.

RESULTS

EEST treatment at 100mg/kg and 200mg/kg p.o inhibited (a) milk-induced increased eosinophilia, leukocytosis, monocytes and neutrophils. (b) Prevented passive cutaneous and active anaphylactoid reactions. (c) Prevented compound 48/80 induced degranulation of sensitized mesenteric mast cells. (d) Inhibited histamine induced pedal edema formation significantly. EEST pretreatment inhibited Shultz-Dale reaction in guinea pig ileum and also elicited potent antioxidant activity.

CONCLUSION

Experimental findings demonstrate promising antiallergic and anti-anaphylactic activity of EEST and also elicited potent antioxidant activity. The antiallergic and anti-anphylactic activity might be due to inhibition of release of chemical mediators from mast cells largely by phytoconstituents like steroidal saponins, triterpenoids and flavonoids present in EEST.

Inhibitory effects of Acorus calamus extracts on mast cell-dependent anaphylactic reactions using mast cell and mouse model

ETHNOPHARMACOLOGICAL RELEVANCE

Acorus calamus Linn. (Araceae) is a traditional herbal plant used for centuries to treat various allergic symptoms including asthma and bronchitis.

AIM OF THE STUDY

The present study was focused to provide a pharmacological basis for the traditional use of Acorus calamus in allergic symptoms using the mast cell-dependent anaphylactic reactions in in vitro and in vivo models.

MATERIALS AND METHODS

Cell viabilities were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Dinitrophenyl-human serum albumin (DNP-HSA) induced β-hexosaminidase and interleukin (IL)-4 productions in IgE-sensitized rat basophilic leukaemia (RBL-2H3) cells were measured by enzymatic assay and enzyme-linked immunosorbent assay (ELISA). Passive cutaneous anaphylaxis (PCA) reaction mouse model was implemented for in vivo studies.

RESULTS

Hot water (HW), butylene glycol (BG), hexane (HE) and steam distilled (SD) extracts of Acorus calamus showed different cytoxicity levels evaluated in RBL-2H3 cells. Sub-toxic doses of HW extract suppressed the β-hexosaminidase secretion and IL-4 production significantly and dose dependently in DNP-HSA induced IgE-sensitized RBL-2H3 cells compared to other extracts of Acorus calamus. Further, in vivo studies also revealed that the HW extract significantly inhibited the PCA reaction in mouse compared to the normal control group.

CONCLUSION

HW extract of Acorus calamus most effectively inhibited degranulation and IL-4 secretion in DNP-HSA-stimulated RBL-2H3 cells and also reduced the mast cell-mediated PCA reaction in mouse, providing a therapeutic evidence for its traditional use in ameliorating allergic reactions.

[Anthocyanidin inhibits immunoglobulin E-mediated allergic response in mast cells]

This study is to investigate the anti-allergic effect of anthocyanidin and to explore its possible mechanism. The experiments of passive cutaneous anaphylaxis reaction (PCA) and colorimetry were used to determine the effect of anthocyanidin on degranulation of mast cells in vivo. For in vitro study, various concentrations of anthocyanidin (100, 50 and 25 micromol x L(-1)) were added to the culture medium of mast cells cultured with 100 microg x L(-1) of dinitrophenyl (DNP) specific IgE overnight. The azelastine (100 micromol x L(-1)) was selected as the positive control. The antigen (DNP-human serum albumin, DNP-HAS)-induced release of degranulation was measured by enzymatic assay, histamine was determined by EIA, and interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were measured by Western blotting, separately. In addition, the effects of anthocyanidin on phosphorylation of NF-kappaB, p38MAPK and Akt were observed by Western blotting. The results showed that treatments with anthocyanidin (100 and 50 mg x kg(-1)) were followed by a decrease in PCA of rats. Anthocyanidin (100 and 50 micromol x L(-1)) obviously suppressed the degranulation from mast cells, whereas results from anthocyanidin (100 and 50 micromol x L(-1)) group indicated significant inhibitory effect on histamine, the calcium uptake, TNF-alpha, IL-6, phosphorylation of NF-kappaB, p38MAPK and Akt of mast cells induced by antigen. Anthocyanidin may suppress the anaphylactic reaction by inhibiting the action of mast cells. NF-kappaB, p38MAPK and Akt at least in part contribute to this event.

[Study on anaphylaxis and hemocytolysis of 6 kinds of tween-80 injection from different souce]

OBJECTIVE

To observe the anaphylaxis and hemocytolysis of 6 kinds of tween-80 injection from different source.

METHOD

The Hartley albinism guinea pig was used to carry on the active systematic anaphylaxis (ASA) and the passive cutaneous anaphylaxis (PCA). The in vitro hemolytic experiment and the hemocytolysis was observed by means of spectrophotometry on the domestic rabbit.

RESULT

The result of ASA and PLA of 6 kinds of tween-80 injection from different source assumed the negative. In observation time, the temolysis rate of 3 kinds of tween-80 injection are more than 5%, while the others are also more than 5% only in the highly concentrated test tube.

CONCLUSION

Six kinds of tween-80 injection from different source have not caused the immune-mediated anaphylaxis, but it may have hematolysis tendency on intravenous injection. The hemocytolysis of tween-80 may not be entirely caused by the impurities. It is worthy of further study that the physical and chemical properties of the product itself and the undeserved concentration is doubtful whether there is also some internal relations with the generation of hemolytic.

The ethyl acetate extract of Cordyceps militaris inhibits IgE-mediated allergic responses in mast cells and passive cutaneous anaphylaxis reaction in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cordyceps militaris has been used as a traditional herbal medicine for treating allergy in East Asia.

AIM OF THE STUDY

We investigated the anti-allergic efficacy of Cordyceps militaris and its mechanism of action.

MATERIALS AND METHODS

β-Hexosaminidase release of mast cells, a key parameter of degranulation, was evaluated. Anti-allergic potential of Cordyceps militaris was studied using passive cutaneous anaphylaxis (PCA) in vivo. The anti-allergic mechanism of Cordyceps militaris was investigated by immunoblotting analysis, RT-PCR and other biological approaches in mast cells.

RESULTS

GSCM EtOAc extract (GSCME) inhibited antigen-induced degranulation with a IC50 value (28.5 μg/ml) in RBL-2H3 cells and antigen-induced passive cutaneous anaphylaxis (PCA) response with a ED50 value (665 mg/kg) in vivo. The release of interleukin (IL-4) and tumor necrosis factor (TNF-α were decreased by GSCME in RBL-2H3 cells. In order to elucidate the anti-allergic mechanisms of GSCME in mast cells, we examined the activated levels of signaling molecules. GSCME inhibited the phosphorylation Syk, ERK, p38 and JNK expression. Identified genistein, daidzein, genistein 7-O-β-d-glucoside 4″-O-methylate, genistein 4'-O-β-d-glucoside 4″-O-methylate, glycitein 7-O-β-d-glucoside 4″-O-methylate, daidzein 7-O-β-d-glucoside 4″-O-methylate and adenosine in GSCME, inhibited antigen-induced degranulation in RBL-2H3 cells.

CONCLUSIONS

Our study suggests that GSCME might be used as a therapeutic agent for allergic diseases.

[Effect of traditional Chinese medicine injections on type I allergy]

OBJECTIVE

To investigate allergic reactions of traditional Chinese medicine (TCM) injections, and to determine the contents of serum IgE and histamine in sensitized animal. The correlation between the preceding contents in serum and allergic reactions may be found, thus offering experimental evidences for advancing the accuracy of anticipation by type I allergy.

METHOD

We carried out passive cutaneous anaphylaxis (PCA) tests,active systemic anaphylaxis (ASA) tests and anaphylactoid reactions using three TCM injections, and determined the contents of serum OVA-sIgE, total serum IgE and histamine in sensitized animals by ELISA method.

RESULT

The results of PCA test were negative, and there was no significant difference for total serum IgE level between experimental group and normal saline group. In the study of adjuvant effect in TCM injections + OVA (at the dose level that doesn't cause allergic reactions), the PCA results of SHL and YXC were positive and there was a increase in content of serum OVA-sIgE, while the PCA result of QKL was negative with a unobvious increase in the content of serum OVA-sIgE. The content of total serum IgE wasn't remarkably increased in each group and the results of ASA test were all positive. Three injections all caused anaphylactoid symptoms in guinea pigs in different doses or injection speed and the response intensity was found to be dosage and injection speed dependant. Furthermore, there was no significant difference for the content of total serum IgE in each group, whereas serum histamine concentration in every experimental group was markedly higher than normal saline group.

CONCLUSION

SHL and YXC increase the sensitivity of guinea pigs on OVA, and three TCM injections can cause allergic reactions in guinea pig. Allergic reactions of three TCM injections are correlated with specific IgE antibodies and histamine contents.

Tanshinones isolated from the rhizome of Salvia miltiorrhiza inhibit passive cutaneous anaphylaxis reaction in mice

ETHNOPHARMACOLOGICAL RELEVANCE

The rhizome of Salvia miltiorrhiza Bunge (SM, family Labiatae), which contains tanshinones as main constituents, has been used as a cardiovascular and anti-inflammatory agent in Chinese medicine.

AIM OF THE STUDY

This study aimed to elucidate anti-allergic effects of the root of Salvia miltiorrhiza Bunge (SM, family Labiatae) and its main constituents, tanshinones, against passive cutaneous anaphylaxis (PCA) reaction.

MATERIALS AND METHODS

PCA reaction was induced by IgE-antigen complex (IAC) in ICR mice. Protein expression of IL-4 and TNF-α in rat basophilic leukemia (RBL)-2H3 cells was performed by enzyme-linked immunosorbent assay and NF-κB and c-jun (AP-1) activation assayed by immunoblot.

RESULTS

Tanshinones inhibited the PCA reaction and reduced IL-4 and TNF-α production in mice as well as in IAC-stimulated RBL-2H3 cells. Tanshinones also inhibited NF-κB and AP-1 activation in RBL-2H3 cells stimulated with IAC. Among tested tanshinones, tanshinone I exhibited the most potent inhibition, followed by 15,16-dihydrotanshinone I, tanshinone IIA and cryptotanshinone.

CONCLUSIONS

SM and tanshinones may ameliorate the PCA reaction by inhibiting the allergic cytokines IL-4 and TNF-α via NF-κB and AP-1 pathways.

Anti-allergic inflammatory activity of the fruit of Prunus persica: role of calcium and NF-kappaB

Mast cell-mediated allergic symptoms are involved in many diseases, such as asthma and sinusitis. In this study, we investigated the effect of ethanol extract of fruits of Prunus persica (L) Batsch (FPP) on the mast cell-mediated allergic inflammation and studied the possible mechanism of action. FPP dose-dependently inhibited compound 48/80-induced systemic anaphylaxis and immunoglobulin E-mediated local allergic reactions. Histamine releasing from mast cells was reduced by FPP, which was mediated by modulation of intracellular calcium. In addition, FPP attenuated the phorbol 12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-stimulated expression and secretion of pro-inflammatory cytokines in human mast cells. The inhibitory effect of FPP on pro-inflammatory cytokines was nuclear factor (NF)-kappaB dependent. Our findings provide evidence that FPP inhibits mast cell-derived allergic inflammation and involvement of calcium and NF-kappaB in these effects.

Inhibitory effects of whisky congeners on IgE-mediated degranulation in rat basophilic leukemia RBL-2H3 cells and passive cutaneous anaphylaxis reaction in mice

Whisky is matured in oak casks. Many nonvolatile substances (whisky congeners, WC) seep from the oak cask during the maturing process. In this study, three antiallergic agents (syringaldehyde, SA; lyoniresinol, Lyo; and ellagic acid, EA) were isolated from WC. Treatment with SA, Lyo, and EA reduced the elevation of intracellular free Ca(2+) concentration ([Ca(2+)]i) and intracellular ROS production caused by FcepsilonRI activation. The inhibitions of the elevation of [Ca(2+)]i and intracellular ROS production by SA and Lyo were mainly due to the suppression of the NADPH oxidase activity and scavenging of the produced radical, respectively. On the other hand, EA inactivated spleen tyrosine kinase and led to the inhibition of the elevation of [Ca(2+)]i and intracellular ROS production. Furthermore, it was found that WC strongly inhibited IgE binding to the FcepsilonRIalpha chain, whereas SA, Lyo, and EA did not indicate this inhibitory effect. These results suggest that WC inhibits allergic reactions through multiple mechanisms. To disclose the in vivo effects of WC, SA, Lyo, and EA, these compounds were administered to type I allergic model mice, and the passive cutaneous anaphylaxis (PCA) reaction was measured. These compounds remarkably suppressed the PCA reaction. Taken together, these findings suggest that WC seemed to be beneficial to ameliorate allergic reactions.

Cycloartenyl ferulate, a component of rice bran oil-derived gamma-oryzanol, attenuates mast cell degranulation

IgE-targeting therapy could provide significant progress in the treatment of allergic inflammation. In this study, we examined the effect of cycloartenyl ferulate (cycloartenol ferulic acid ester; CAF), a natural product from rice bran oil-derived gamma-oryzanol, on allergic reaction. When CAF and gamma-oryzanol were injected intradermally with anti-DNP IgE into the dorsal skin of rats, the passive cutaneous anaphylaxis reaction induced by DNP-HSA was attenuated. CAF and gamma-oryzanol also inhibited the degranulation of DNP-IgE sensitized RBL-2H3 mast cells stimulated with anti-DNP-HSA. IgE conjugated with CAF could not be detected by anti-IgE antibody in the ELISA analysis. Although incubation of IgE with CAF did not decrease the amount of IgE, it was possible to precipitate IgE by centrifugation. These results demonstrate that CAF captures IgE, prevents it from binding to FcepsilonRI, and attenuates mast cell degranulation.

Anti-allergic effects of scoparone on mast cell-mediated allergy model

Scoparone is known to have a wide range of pharmacological properties in vitro. However, the roles of scoparone in immediate-type allergic reactions have not yet been investigated. In this study, we demonstrated that scoparone attenuated IgE-mediated allergic response in mast cells. Oral administration of scoparone inhibited passive cutaneous anaphylaxis in rats. Presence of scoparone dose-dependently decreased histamine release from rat peritoneal mast cells (RPMC) stimulated by anti-dinitrophenyl IgE. Moreover, scoparone reduced the expression and secretion of pro-inflammatory cytokines, such as tumor necrosis factor-alpha and interleukin-6 in RPMC. Pretreatment with scoparone inhibited the calcium uptake and p38 mitogen-activated protein kinase (MAPK) activity. Furthermore, scoparone blocked translocation of nuclear factor-kappa B (NF-kappaB) p65 subunit by suppressing IkappaBalpha phosphorylation in RPMC. Reduced calcium uptake as well as the suppressed activity of p38 MAPK and NF-kappaB might be involved in the inhibitory effect of scoparone on the secretory response. Our findings suggest that scoparone may serve as an effective therapeutic agent for allergic diseases.

Mangiferin inhibits passive cutaneous anaphylaxis reaction and pruritus in mice

The antiallergic effect of mangiferin isolated from the rhizome of Anemarrhena asphodeloides Bunge (family Liliaceae) was measured in vitro and in vivo. Orally and intraperitoneally administered mangiferin potently inhibited passive cutaneous anaphylaxis (PCA) reaction induced by IgE-antigen complex as well as pruritus induced by compound 48/80 in mice. Mangiferin also inhibited the expression of the proinflammatory cytokine TNF-alpha and the IgE-switching cytokine IL-4 as well as transcription factor NF-kappaB activation in RBL-2H3 cells stimulated by IgE-antigen complex. These findings suggest that mangiferin may improve PCA reaction and pruritus.

[Determination of the allergic impurities in the parenteral injection of Chinese traditional medicines containing Salvia miltiorrhiza]

The residual protein mixture (the content is 4%, approximately), called Salvia miltiorrhiza antigen, was extracted from the Salvia miltiorrhiza cruel materials by mimicking the alcohol-deposit extracts process. Both rabbits and guinea pigs sensitized by Salvia miltiorrhiza could produce specified antibodies. Large molecular antigenic impurities were extracted from the Danshen injection and Xiangdan injection using the centrifugal filtering method. The test results of active systemic anaphylaxis (ASA) and passive cutaneous anaphylaxis (PCA) in guinea pigs confirmed that the extracted antigenic impurities could induce the anaphylaxis reaction in the animals which were sensitized by the Salvia miltiorrhiza antigen. Using the specified antibody produced from rabbits which were sensitiyed by Salvia miltiorrhiza, ELISA test method was developed to test the residual Salvia miltiorrhiza antigenic materials contained in the parenteral Chinese traditional medicines. Calculated as residual protein, the linear range was 0.08-5.12 microg x mL(-1) (r2 = 0.9906), the detection limit and quantization limit are 0.08 microg x mL(-1) and 0.4 microg x mL(-1), respectively. 308 batches of parenteral Chinese traditional medicines containing water-soluable components of Salvia miltiorrhiza were tested, and the Salvia miltiorrhiza antigenic impurities were spotted in 35 (11.4%) batches of samples. The test results show that the extracting process currently used can not remove the Salvia miltiorrhiza antigenic impurities completely, and this may be one of the reasons for anaphylactic reaction in clinics. The proposed ELISA method can be used for improving the manufacture process and for routine quality control of drug products.

[Anti-allergic effects of Rubus suavissimus extract]

OBJECTIVE

To investigate the effects of Rubus suavissimus S. Lee extract (RSE) on mice, and its influence on release of histamine from rat peritoneal mast cells induced by compound 48/80 in vitro.

METHODS

To establish murine delayed-type-hypersensitive model induced by 2,4-dinitrofluotobenzene (DNFB) and sheep red blood cell (SRBC); murine type I allergic reaction induced by PCA, and then to observe the anti-allergic effect of RSE. HPLC-ECD methods were performed to detect the contents of histamine released from rat peritoneal mast cells induced by compound 48/80 in vitro.

RESULTS

Compared with the model group, RSE could ameliorate the ear swelling and capillary permeability in mice induced by DNFB and PCA. RSE also reduced the thickness of the mice hind paw induced by SRBC in significant dose-dependent manner. Meanwhile, RSE obviously inhibited the release of histamine in rat peritoneal mast in vitro, a dose-dependent manner.

CONCLUSION

RSE exerts potential anti-allergy effects and the mechanisms may be partly related to its inhibitory effect on the release of histamine from mast cells.

A saturated N-acylethanolamine other than N-palmitoyl ethanolamine with anti-inflammatory properties: a neglected story

N-acylethanolamines, which include the endocannabinoid anandamide and the cannabinoid receptor-inactive saturated compounds N-palmitoyl ethanolamine and N-stearoyl ethanolamine, are ethanolamines of long-chain fatty acids degraded by fatty acid amide hydrolase (FAAH) known to accumulate in degenerating tissues and cells. Whilst much evidence supports a protective anti-inflammatory role of both anandamide and N-palmitoyl ethanolamine, very little information is available with regard to the bioactivity of N-stearoyl ethanolamine. Employing a murine model of passive IgE-induced cutaneous anaphylaxis, we have found that N-stearoyl ethanolamine is endowed with marked anti-inflammatory properties in vivo, supporting the hypothesis that endogenous N-stearoyl ethanolamine is, in analogy to N-palmitoyl ethanolamine, a bioactive signalling lipid capable of downregulating allergic inflammation in the skin. This effect, although mimicked by synthetic, non-selective, CB(1)/CB(2) receptor agonists, such as WIN55, 212-2, was not sensitive to CB(1) or CB(2) receptor antagonists, but rather was fully reversed by capsazepine, a competitive antagonist of the TRPV1 receptor. Moreover, CB(1) receptor antagonists, although effective in antagonising the WIN55,212-2-induced hypothermia, did not reduce the anti-inflammatory effect of WIN55,212-2, whilst CB(2) receptor antagonists, per se inactive, potentiated the WIN55,212-2 effect, suggesting an involvement of non-CB(1)/CB(2) receptors in the anti-inflammatory action of WIN55,212-2. All this, together with demonstration of FAAH as a major regulator of the in vivo concentrations of saturated N-stearoyl ethanolamine, in addition to N-palmitoyl ethanolamine, raise the speculation that pharmacological treatments with saturated N-acylethanolamines such as N-stearoyl ethanolamine, or alternatively FAAH inhibitors able to increase their local concentration, rather than selective CB receptor agonists, might be of promising therapeutic benefit in reducing allergic inflammation in the skin.

Antiallergic effects of Vitis amurensis on mast cell-mediated allergy model

In this study, we investigated the effect of the methanol extract of fruits of Vitis amurensis Rupr. (Vitaceae; MEVA) on the mast cell-mediated allergy model and studied the possible mechanism of action. Mast cell-mediated allergic disease is involved in many diseases, such as asthma and sinusitis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. MEVA inhibited compound 48/80-induced systemic reactions and serum histamine release in a dose-dependent manner in mice. MEVA decreased immunoglobulin E (IgE)-mediated local allergic reactions, passive cutaneous anaphylaxis. MEVA dose-dependently reduced histamine release from mast cells activated by compound 48/80 or IgE. The inhibitory effect of MEVA on histamine release was mediated by the modulation of intracellular calcium. In addition, MEVA attenuated the phorbol 12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-stimulated secretion of tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-8 in human mast cells. The inhibitory effect of MEVA on these proinflammatory cytokines was p38 mitogen-activated protein kinase and nuclear factor-kappaB (NF-kappaB) dependent. Our findings provide evidence that MEVA inhibits mast cell-derived, immediate-type allergic reactions and involvement of proinflammatory cytokines, p38 MAPK, and NF-kappaB in these effects.

Lactic acid bacterial fermentation increases the antiallergic effects of Ixeris dentata

Ixeris dentata (ID, family Asteraceae), called Seumbakuy in Korea, was fermented with lactic acid bacteria (LAB) and their antiallergic activities were investigated. Fermentation of ID with Bifidobacterium breve or Lactobacillus acidophilus increased its inhibition of degranulation in RBL-2H3 cells induced by the IgE-antigen complex. Oral administration of these extracts to mice inhibited the passive cutaneous anaphylaxis (PCA) reaction induced by the IgE-antigen complex and scratching behaviors induced by compound 48/80. The fermented ID more potently inhibited the PCA reaction and scratching behaviors than the non-fermented one. These extracts also inhibited mRNA expression of TNF-alpha and IL-4, as well as NF-kappaB activation in RBL-2H3 cells induced by the IgE-antigen complex. These findings suggest that LAB fermentation improves ID-mediated inhibition of IgE-induced allergic diseases such as rhinitis and asthma, and that ID works by inhibiting degranulation and NF-kB activation in mast cells and basophils.